Since I’ve owned my 1966 Bronco it never got past 3rd gear for years and I drive the freeways in Los Angeles all the time.

Finally I collected the parts to install my new NV3550 and a twin-stick shifter I purchased made for an early Bronco.

The problem simply was the twin-stick shifter wasn’t designed with the offset of a NV3550 in mind. With the mounting bracket of the twin-sticks, the bracket supplied by Advanced Adapters, and the height of the shifters I could see it wouldn’t work.

I wanted to have a clean twin shifter that would not be killing my right knee all the time and cleared the shifter from the NV3550. Additionally I wanted to close the whole in my floor where the 3speed shifter was previously installed. So I decided to design and fabricate my own shifters and a sheet metal floor patch or access panel which would allow me to install a stock carpet kit one day. After all these are just two levers on a common pivot point, right?

Parts and Supplies Needed:

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I didn’t like the way prefab tubing fit; it had too much play. Instead I took solid metal rods and drilled them to make snug fitting tubes for my pivot points.

Including machine shop expenses and materials my total spent was just under $80 not including tax or shipping.

Fabricating The Floor Patch.

1. Measure the whole in your floor that needs to be covered.

2. Cut out a large piece of paper from a grocery bag. Making sure your lines are square, draw the outline of the patch to make your template. I added a 3/4 inch tab on the edges to allow for the tabs to make a physical connection over the existing floor. I also labeled the template to show front and top.

3. Double check your measurements, measure twice, cut once. With that said, cut out your paper template and fold it to match the different angles of the floor. When you are satisfied with your paper template carefully trace it onto your sheet metal. For my patch, I used a scrap piece from an old hard top.

4. After double checking your measurements, cut out your sheet metal patch. You can use a cut off wheel on a grinder or sheet metal sheers. I prefer to use my electric sheet metal sheers from Harbour Freight.

5. To make my bends I have several pieces of extra metal bar around the garage I use to bend my sheet metal patches. Here I clamp the first bar under the patch with two vice grips at each end. Next I clamp the other bar on the top side of the tab which I am going to bend down. I couldn’t find my extra vice grips so I just used a channel lock instead and slowly bent my first tab.

6. Check your bends often during this process. Bend the patch carefully and make sure you apply even force to keep your bends straight. This takes a bit of back and forth work to check each bend as you go.

7. With the bends completed, try a test fit. At this point the big whole in my tunnel was completely covered.

8. Sand, paint or coat the patch to match your floor. I Herculined my floors so I did the same to the patch and let it dry. Later on you will be removing a portion of your new patch for the shifters to come through the floor so you may want to wait to paint the patch until the end of this project.

Fabricating the Twin-Stick Shifters

Their Shifter

Our Shifter

1. The first thing to establish here is what transmission you are using and does it come with a mounting bracket for the 4×4 shifter. In my case Advanced Adapters provided this backing bracket with the NV3550 kit. All I needed to do was drill a 7/16 diameter hole in the center for the pivot point of my shifters. For you, you may want to fabricate a bracket of your own depending on your transmission. A simple solution is a flat metal bar with 3 holes drilled into it. [The correct length will vary depending on your application.] Your mounting bracket will require two outer holes to be drilled for mounting the shifter to the transmission and one hole drilled in the center to mount the pivot point for your shifters. With my setup I drilled a 7/16 hole into the center of the bracket supplied by Advanced Adapters. I then welded the 7/16 course thread 4 ¼ inch grade 5 bolt used for the pivot point. Later this 7/16 bolt was trimmed to the exact length required.

2. With my high quality napkin and tin foil I made 2 bendable templates for the upper rods of the shifter. I started by rolling the foil with the napkin in the center and then cutting the foil rods into two 12 inch length.

My goal here was to first shape the rear axle shifter then the front axle shifter. I wanted to have the end result to allow clearance for the two shifters to be able to move freely with out binding up when the shifter knobs were installed. Also I wanted them to be low enough to allow for full shifting of my NV3550 shifter in all gears and for clearance to my left knee to not hit at all. Last but not least the ending product had to be able to fit under my sheet metal patch for the floor. Easier said than done.

3. With the mounting bracket installed onto the transmission I next installed two 1 ½ inch long pieces of drilled metal rod onto the pivot bolt. The shifters and lower arms will later be welded to these with washers and a lock nut.

4. I designed the rear axle shifter to be in 2 wheel high when the shifter was in a low position on the floor with the shifter knobs both being at an equal height when in all positions. Forming the foil rod here took some practice, imagination for future clearance, and some trimming. At this step I marked on the inner tube with a Sharpie the position of the foil rod and drew two alignment lines from the foil rod to the tube.

5. I repeated this step for the front axle shifter. To make sure I was going to have the desired end result I had a flat piece of card board I used to cover the large tunnel hole to represent the sheet metal floor patch. I trimmed a small hole in the card board allowing for the foil rods to poke up through the floor.

I used a small amount of blue masking tape to hold the shifters in place at times while I shifted the foil rods through all positions.

6. To bend the metal rods I strongly recommend you cover the threaded end of the rod with a lot of making tape. Don’t screw up the threaded ends of the rods. Start from the top of the rod and make your way down. This helps to protect the threaded end from accidentally being crushed when using the long pipe/breaker bar to bend the rod.

7. Starting with the first bend, compare the foil rod to the metal rod marking on the metal rod a line where the first bend is to be done. Carefully place your metal rod in one side of your vice, the foil rod in the middle, and a small 1 inch piece of scrap metal rod on the left side in the vise. Line up the mark on the metal rod with the edge of your vice, place your long pipe/breaker bar over the metal rod and slowly bend.

This was tricky and very time consuming. You will do step 7 over and over before achieving the correct shape of your metal rods.

8. You may want to cut the non-threaded ends of the shifters to the correct length for your application. This will very depending on your body lift height. Try to contour the end of the rod with the grinder so it will fit over the pivot point metal tubes.

9. Tack the rods into place but do not weld them completely just incase you need to reposition them later.

10. With the rods tacked in place, remove the protective tape from the threads and mount your shifter knobs. Try moving them freely, imagining where you want the final location of 2 wheel high and 2 wheel low to end up.

11. At this point I found the metal tubes could be trimmed allowing the shifters to be installed closer together. I trimmed them just a little at a time, installed the 7/16 washers, and the lock nut loosely.

12. Cut two pieces of the 1 metal bar, a 3 inch, and a 4 inch piece. Cut out a shape with two long outer finger which fit over the metal tubes at the bottom of the pivot(See the parts photo). The rear axle arm will be somewhat shorter than the front axle arm. Grind out a slight angle on the inside of the bar between the fingers.

13. Drill a ¼ inch hole about ½ an inch away from the end of the two bars. Take some time to view the movement of the arms under the metal tubes. When I got the angles right here I tack welded them into place.

14. Cut two pieces of ½ inch wide card board strips. These will connect the bottom of your shifter arm to the transfer case rails. At this point the length will vary. The rear shifter connection bar was about 3 inches and the front shifter connecting bar was almost 5 inches long. Your exact length will vary. (The pair in the photo were too short, I made another set) Double check the movement with the card board connecting bars first. Next cut to length your metal bars and before you start to do any bending, drill 2 ¼ inch holes at the ends of each.

15. To bend the lower arms of the shifter I placed it in the vice and used a large adjustable crescent wrench to make my final adjustments. Keep the bends in the middle of the bars not at the ends. The ends will require flat surfaces for the connections at the clevis pins to move freely. Also some twist will be needed to make the connection rods move freely. Try assembling the shifter and moving it check to make sure it doesn’t bind up.

16. Cut the clevis pins to length and welded them into place on the lower arms of the shifter. At this point I did my final welding making it very solid.

17. Paint. I filed the metal tooth marks from my vise off, cleaned the metal with acetone, masked off the threaded ends and gave the shifters 2 coats of semi-gloss black paint. I also prepped and painted the sheet metal screws too.

18. Finally I installed the twin-stick shifters, trimmed the sheet metal floor patch, and installed the patch, and shifter boot. The trim ring did also need some adjusting to make it fit flat on the floor.

After all said and done I am very happy with my ending result. If anyone has questions please feel free to contact me.
Chris taipeichris13@yahoo.com

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To make things much easier first go the website of the Lonestar Early Bronco Club. Go to TECH, INFORMATION, KOENIG WINCH INFO. Print off a copy of the PTO EXPLODED VIEW. I will refer to and give you a cross reference of some of the numbers on this exploded view of the pto.

Before beginning disassembly have a notepad and camera available to make notes and take pics of the entire process.

My PTO I have photos of is different than the page you printed off of the Lonestar site. The photos are of a PTO with a front and rear output shaft. The only difference is that the out put shaft is longer, and in place of the rear bearing cap #65-8, mine uses a bearing cap with a seal in it just like the front output shaft has,#65-10 with seal # 65-18.

New parts needed are:

• bearings (cones & cups) 2 each Timken #LM67048 & #LM67010 (replaces Koenig #65-17).
• Needle bearings ( qty.2) Timken #B1416 (replaces #65-16).
• Oil seal (qty.1) CR #6315 (replaces #R35)
• Oil seal (qty.1) CR #12336 (replaces #65-18)
• O-ring (qty. 2) Motion Ind. #00619831 (replaces #65-19)
• New parts were purchased at Motion Industries.

Begin by removing the old gasket that was between the pto and transfer case. Remove allen set screw #65-26. With a brass drift punch tap input shaft out of case. The two washers may fall into the case, these can be retrieved later. Set aside all the parts that were on the shaft. Remove detent plug, spring and ball. Remove shifter yoke from shifter shaft and take shaft out of case. Take bearing caps off of output shaft. Remove bearings from case then remove the split lock ring from the shaft. Tap output shaft shaft through gear and out of case. Remove any parts from case that may have fallen in.

Degrease and clean all parts, let dry and wipe with clean cloth.

At this point you may want to paint or coat the case. I used the POR 15 system. Marine clean ,metal ready and their Silver paint. Clean machined surfaces of paint at seal openings, bearing bores and input shaft bore. Remove needle bearings from input tube. I used a deep well socket that was slightly smaller OD than the new needle bearings and pressed the old bearings out of the tube.
Note: Put a light coat of oil on all bearings before pressing into place.

To begin assembly:
1) install new seals into bores at shifter shaft and bearing cap.

2) Press bearing cup in case at front output shaft bore.

3) Seat bearing cup to correct depth by installing bearing cap, tighten bolts sequentially.

4) Remove the bearing cap and bolts.
5) Place bearing cone into case and into bearing cup.
6) Carefully set output gear into case.
7) Install two piece lock ring onto output shaft.
8.) If large woodruff key came out of shaft replace it now.
9) From back side of case install output shaft through opening with 7/8″ diameter end of shaft into case and through gear lining up key and keyway and centering through bearing on front side of case.

10) With case on its front side and supported around bearing opening center shaft in bearing and tap in place with hard rubber hammer.

11) Slide spacer onto output shaft.
12) Place rear bearing onto shaft, install cup on bearing, tap in place.
13) Seat rear bearing in place as in step #3.
14) Lightly coat the bore of the shifter shaft oil seal and carefully slide in shifter shaft approx. 2″.
15) Place shifter yoke in case and slide shifter shaft through yoke.

16) Rotate shifter shaft so that the small groove will be in line with the detent plug ,spring and ball.
17) Place bolt with lockwasher through shifter yoke and tighten into tapped hole in shaft.

18) Insert spring into detent plug, place ball on top of spring, hold the case so you can thread the detent plug assembly into the case.

19) Test shifter shaft operation, you should be able to feel positive stops at the engaged and disengaged positions.
20) Press both needle bearings into input tube.
21) Place input tube into sliding gear with key and keyway lined up.

22) Set sliding gear and tube onto shifter yoke.
23) Place an o-ring on the front end of the input shaft.(rear of the input shaft has the groove for the setscrew to index into, inboard of the o-ring groove).

24) Start rear of input shaft into bore, just before end of shaft enters case cavity place one washer inside case lined up with bore, push shaft through washer and into input tube.
25) Place the other washer at the rear of the input tube, between input tube and case, continue to push shaft through washer and into rear bore. Shaft will stop when o-ring touches front bore.

26) Tap front of shaft through bore just enough to expose o-ring groove on rear of shaft.
27) Place o-ring into rear groove and tap shaft back into bore. Center shaft in front and rear bores. Install setscrew into case to lock input shaft in place.

28) Using PERMATEX ULTRA-BLACK RTV SILICONE GASKET MAKER use on bearing caps instead of gaskets. Follow directions on package.

29) Install bearing caps.

30) PTO is ready to be installed on transfer case.

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Is your t-case shifter so sloppy that you can hardly get it into gear? Well I found a cheap and easy fix for this problem. Even if the shifter is still in the truck this should take less than an hour and cost less than $10.00.

Here’s what you need:

• 1 or 2 brass bushing totaling 1 and ¾ inches(depends on long of a bushing you can find in the store, I used 2- 1’’ bushings) O.D. 11/16ths I.D. ½ inch
• 1- ½ inch grade 8 bolt 5 inches long(5 ¼ if you measure the head of the bolt as well)
• 1- ½ inch Nylock nut(see pic)
• 2 flat washers

All of these items can be purchased at your local Lowe’s for less than $10.00.

In the base of the shifter where the bolt goes through to attach it to the intermediate housing, there was apparently some sort of bushing that came with the shifter from Ford. I am assuming this because the hole that the bolt goes through on the shifter is 11/16ths and the hole in the intermediate housing is ½ inch. My shifter had no such bushing and the shifter was extremely sloppy.

So what you do is take the brass bushings and coat them with a little wheel bearing grease and GENTLY tap them into the shifter. If you hit them too hard they will break off. I had about a ¼ inch left sticking out of my shifter but a cut off wheel made short work of that (what was left is what is in my hand in the pic). This is important… take a ½ inch drill bit and run it through the inside hole of the newly inserted brass bushings. They will have warped a little bit and gotten squeezed from the insertion process and this will clean out the hole. Test the bolt to make sure it will rotate in the bushings without restriction. Put a little grease on the bolt as well.

Put one washer on the head of the bolt and put the shifter back into place on the t-case. Stick on the other washer and the Nylock nut and tighten to your preference. The purpose of the Nylock nut is so that you can tighten the shifter down to your liking and never have to worry about it backing off and falling off. Some guys like their shifters to move a little easier than others.

Hook up the shift rail piece and give her a try, you’ll be amazed at how much easier you t-case will shift into and out of gear when the slop is gone out of the shifter. This will NOT eliminate all of the slop because there are other components involved, i.e. the shift rails, the connector piece that connects the shifter to the rails and possibly the hole in the intermediate housing. That said this simple fix will help a great deal with the majority of this common problem.

Happy wrenching,

Tech article by smokeater11

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The history behind my choice: (Skip this if you just want to know what parts were required and how I did it)

The following article describes the C6/203/205 doubler assembly I installed in my 69 Bronco along with my reasons for choosing this setup over the other options available. The main reason I’m writing it up is that I’ve answered the same questions many times both on and off the message boards regarding the details of my setup.

To start with I’ll go through a bit of the history behind my choice. Basically I knew that the C4 in my Bronco was slowly dying and therefore I began looking at different transmission options. Not that the C4 isn’t a decent transmission, but rather that it just wouldn’t live with the way I was abusing it. My primary goal when building up my rig has always been that whenever anything breaks I try to upgrade it to something better that will not break the next time around. My preference is to do it once and do it right. With this in mind I began my search.

To start with I began looking at direct bolt in options with better gearing choices. This pretty much left me looking at a transfer case change at the same time unless I purchased an expensive adapter. I pretty much decided right from the start to go with a NP 205 transfer case because their strength is legendary. The main issue with them is that the low range is only 1.96:1 which did nothing to help me in the low gearing department. To get around this I began looking at transmissions with more gearing options. First I looked at the AOD transmission using the wide ration gears. I dismissed this option though due to reservations I had about it being strong enough. Next I looked at the ZF transmission which I almost ended up using. At one point I would have bought one if the clutch parts would have been on it. (At that point I had already decided on the ZF and was just finding parts to do it) By that point I had also run across information on doing a 203 doubler and I was giving it serious consideration.

At about the same time a discussion was also going on regarding automatic transmissions and taking the torque converter into account when figuring crawl ratios. Since my primary reason for choosing the ZF over the others was the crawl ratio I quickly ran some searches to dig up what information I could on the subject of crawl ratios when using torque converters. The information I turned up both surprised me and also made complete sense. It answered the gnawing question I had as to why auto transmissions had higher gears than manual ones. Basically it boiled down to the torque converter which slips when it is at speeds lower than the stall speed which in essence creates much lower gearing than the actual gears in the transmission. The actual conversion numbers vary from one torque converter to the next, but they usually fall between 1 1/2 to 2 1/2 times the low gear in them for calculating the crawl ratio. A quick calculation in my head put the 2.46 ratio in my current C4 at about 5:1 for calculating the crawl ratio so it became quickly apparent that the ZF wasn’t going to be a big advantage there and that it would sacrifice the convenience of the auto transmission. Back to the drawing board I went.

Specifically I looked at the C6 at this point because it had the same gearing as the C4 I was already using and because it is also known for its legendary strength. This time though I took into consideration that I could use a 203 doubler at the same time. A few calculations later and I came up with the following: The C6 low gear is 2.46:1, the NP 203 range box low range is 2:1, the NP 205 has a low range of 1.96:1, and I was running 4.56 gears. This gave me a crawl ratio of 44:1 before taking into account the torque converter. After taking it into consideration though it put my crawl ratio at somewhere between 66:1 and 110:1 with a median calculation of 88:1. I figured that my crawl ratio would be somewhere in the neighborhood of 90:1 using this setup.

Some of you may be wondering at this point why I didn’t look at the Atlas. Well, there were a few reasons. First is that they are hard to obtain if they break. I.E. You can’t run to the local wrecking yard for parts. Second is that they cost a lot of money. I figured approx. 3 or 4 times the cost of doing the doubler setup instead. Last is the gearing options. Basically you are given two choices; Either go fast or go really slow. Nothing in between. With the doubler I get the options of running 1:1, 2:1, and approx. 4:1. I could take this a step further and have the gears in the 203 swapped out for a 3.1:1 low range set as well to give me even more options. Doing that would give me 1:1, approx. 2:1, 3.1:1, and about 6:1. Some day I might go this route along with the low gear set I plan to put in the C6 which would give me a crawl ratio of about 160:1. At a cost of a cool grand though this will wait for awhile.

Since I brought up the low gear set for the C6 I’ll briefly cover it. Basically it uses a wide ratio gear set from a newer Ford transmission (There are two option) which basically drops the low gear enough to make up for a normal gear swap of say 4.56 to 4.88 gears. Another word with it installed my low gear would feel like I was running 4.88 gears instead of 4.56 gears. They are also supposed to hold up well in the C6 in contrast to the C4 ones which are not very reliable.

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This is my write up for the 3 speed manual and transfer case removal, seal replacement and new gaskets. I recently purchased my ‘69 bronco and got it on the road. Now that it’s on the road after sitting for 15 years or so, some of the gaskets and seals are hammered. Good excuse to tear them down, clean them up and throw some paint on them.

Step 1: The first thing you need to do is remove the tranny, intermediate housing and the transfer case. Not as easy as it sounds so what we do first is make some room to work.

Step 2: I am lucky enough to have fresh unrusted exhaust that I can unbolt from the headers. Without the mufflers in the way I now have room to work and get my wrenches in there to start ripping things apart.

Step 3: Unbolt the front and rear drive shafts (8 bolts per drive shaft). Remember your drive shafts are balanced, so mark them so you can rebolt them to the yolks in the same position they came off.

Step 4: My next step was to unbolt the cross member from the frame rails. You’ll have to use a socket on the top to hold it it place while you loosen the bottom nut. It was a little tight. A body lift would’ve been nice to help out. Eventually I took out the two inner bolts that connect to the intermediate housing adapter so you might as well do that now. Pull out the bushings from those bolts and if they are in bad shape it’s a good time to replace them when you reinstall this.

Step 5: You want to unbolt the 1 bolt that holds the speedometer gear in place. Then pull it out and push it out tof the way. This is located on the back of the transfercase up high.

Step 6: The next step is to pull off the shifting linkage. In my case I have a Hurst floor shifter and a T shift for the dana 20 t/case. I was told to put it in first gear and leave it there until reassembled. Something about pin bearings falling out or something. I’m not real sure, I just did it. A couple bolts holding the Hurst floor shifter handle in place were removed for that. Now the t/case shifter has 1 big bolt that runs through the top of the t/case. Find a friend to hold that nut from underneath while you loosen it from the top. Then there’s a cotter pin holding the rest of the handle to the shift rods. Remove that and that part is done.

Step 7: Now for the hard part; “pulling it all out.” You definitely need a friend or 2 to help along with a jack. This thing is pretty heavy, close to 200lbs probably. I removed the cross member 1st so that I was able to pull down and back at the same time. 1st loosen the 4 bolts from the tranny to the bell housing. Before you do that and the cross member set up the jack to keep it up and level. Now pull it out. It has to come back about 5-6 inches before it’s out.

Step 8: Now that it’s out, clean it up so you can paint it later. Better to clean it now rather than later when you have things falling into spots you don’t want them in. I used brake and parts cleaner along with a toothbrush size wire brush. Get it all good because paint will not stick to grease.

Step 9: Next is remove the bolts from the back of the tranny to the adapter. I had to tap it a few times with a hammer to break it loose. You’ll have to pull it about 5-6 inches also because of the shaft on the back.

Step 10: Now you can start to replace gaskets and seals. Unbolt the 9 bolts from the top of the tranny and pull the top off. Clean the old gasket off and slap on the new one. I used a little silicone gasket sealant on one side before I put it back on. Do this with all the gaskets you replace.

Step 11: The front of the tranny has a seal it it. Undo the 4 bolts on the front of the tranny shaft. Now slide the cover off and you will see the seal. Replace it and put a new gasket on. The tranny is done.

Step 12: Intermediate housing adapter seal, O-ring and removal. Now remove the 6 bolts that connect the t/case to the adapter. Be careful when you pull them apart there are pin bearings that may fall out of place. I was lucky they didn’t. Now that it’s out, where the gears are you need to pull the first clip off. Now slide the gear off. Next is the bearing retaining clip. Pull that out and slide the whole shaft and bearing out. Now you have access to the seal. I used a long screwdriver and a hammer to knock it out. I tapped it from the opposite side through the entire adapter. Put in the new seal, bearing and shaft, clip, gear, clip and you’re done! Don’t forget the big O-ring that goes over that gear and flange that you just did. Put the new gasket back on when your ready to put it back together.

Step 13: The t/case seals I chose not to do at this time. First because they weren’t leaking and second they are easily accessible while it’s on the truck. I will however do the big gasket on the plate with the 10 bolts.

Step 14: I used high temperature red-orange paint with ceramic in it. I figured since it’s out I might as well make it look nice too. The finish is rock hard and nice and glossy. While this is all out of the truck it’s also a good time to do the clutch (my next write up) and also spray a few cans of undercoating.

Step 15: Now all you have to do is put it back in the truck.

Tech article by Josh Wilczynski (kontinu)

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Well, I said I would do a bit of a blow by blow account of the fight to install a 203 so here goes….. Got the Dodge 203 from a salvage yard in WI. Had it shipped to me in TX and saved a bundle still. (really shows the ass of most yards here in TX) Anyway, I already vented about that a while back. The 203 came out of a 78 Dodge 4×4 and are very abundant. Should have no probs finding on…..check www.carparts.com. I had to wimp out a bit when it came to adaptors due to the fact that the machinist that was going to work with me landed a HUGE contract and didn’t have anytime for the foreseeable future, so I ordered up the Wild Horses Kit that Advanced Adaptors made. GREAT KIT.

Very inclusive and complete, and hell even has pictures on the directions for me! Gotta love that! I will be calling WH and speaking with someone in management that this is a good job.Here’s what I got done today…..
Took apart the 203…..it is two pieces for the most part and all I will be using is the gear reduction half. The chain drive 4×4 part is official anchor weight. BE SURE YOU KEEP TRACK OF ALL ROLLER BEARINGS! As usual, I spent too much time chasing these things around. You will need to keep the bearings that occupy the 203 output shaft. Everything from the aluminum keeper back, off the 203 is transferred to your new set up. I was lucky enough to have two 435 setups so I could go ahead and put together the entire new 203 to D-20 shaft assembly. It consists of:

• New 203 to D-20 Output shaft (kit)
• Original 203 2:1 (large) gear
• Original spacer
• Original Output shaft bearing and carrier (big slotted aluminum thing)
• New D-20 Bearing Retainer and sealer (you will recognize this from a 435 set up)
• Original D-20 input gear assembly.

Keep all of your snap/retainer rings! You will need these. Tomorrow (if time permits) I will get the tranny and stuff out of the rig and get the New NP435 Output shaft in the tranny. That will pretty much take care of the hard stuff…Well its tomorrow and that wise crack the hard stuff is over is all CRAP. These things weigh a ton all put together!!!!!! Here is the account today…….

Got the 435 out of the rig and the D20. Pulled the cover off the top of the 435 to see what I am up against and found that my tranny is also a great water catcher. The milkshake goo that I found in there is quite amazing.

Anyway, finished cleaning that out and put to work taking the main shaft out of the tranny for the new main shaft swap. Steps:Take the rear output bearing off as well as the front input bearings off. The front will come apart and the shaft will be in two pieces. You have to have that rear bearing out of there also so you can tilt the shaft enough to get it out of the case. REMEMBER…there are roller bearings in that front input part. PITA trying to get those out of the bottom of the case. Here is a pic of the new main shaft (one with NO gears) and the old main with all of the gearing still attached. That’s the rear bearing as well lying there. Shorter is the main difference and a new output spline count.

Take a note on how your gears go on the shaft when you transfer them to the new shaft. There is really only one way, but if you remember and note in the first place then you will save a bit of time.NOTE: When the large gear comes off…..it only comes off the front of the shaft. There are two metal …….”things”. Because I tilted the shaft just so the large gear slid off and I didn’t take note of where these *&E(%&($(# ! things went. Took me quite a long time to figure that one out with no manuals to refer to!

Anyhoo…….now reverse the process with the new shaft and reinstall back into the 435. There will probably be a bit of resistance with bearings and stuff like that due to new parts, so things my fit a bit tighter than they came off. I had a press for things like bearings (rear bearing specifically) to put it on the new shaft. You may or may not need this, but always be careful with your bearings. YOU WILL ONLY WANT TO TAKE THIS THING IN OR OUT ONCE! I promise! Here is a pic of the gears bearings ( the evil roller bearings as well) with the old and new shaft.

The adaptors are pretty much simple on the hows and whys. There are supplied allen bolts that are counter sunk for bolting to the 435 and d20.

Its hard to see from this pic above, but on this adaptor at the 6o’clock position you have to preinstall this bolt, due to the fact that the 435 reverse gear bearing housing bumps out a bit from the tranny case. Having this bolt in first is the only way to get it in.

Here is the 203 gear redux box. Top pic is the side that will mate to the d20 and that adaptor. Second pic it the 435/203 side . Again, you will use some parts from you existing 435/d20 set up right now, like the aluminum housing that fits into the D20 with the seal….

Above are the fully assembled shaft gears and bearing that runs between 203 and D20. Left side to 203, right side to d20.

D20 and 203 together. The POR 15 was pristine for about 15 minutes until I touched it again and drug things all over the concrete.

My helpful daughter Andi!

This kit does not have any gaskets so liberal use of silicone was the SOP on all mating surfaces.

For the install back into the rig, I did the 435 first by itself and then the 203/D20 assembly second. In hind sight, I would have probably left the 203/D20 apart just for sheer weight factor and difficulty in handling. I have the entire top of my tranny tunnel cut out anyway so that helped me in that I ran rope around the 203/D20 up to my roll cage for assistance. If you do a 3 part install, again WATCH YOUR ROLLER BEARINGS in the 203 on the d20 side. The 203 is a snap bolting it to the 435, then you get to do the roller bearing fight when installing d20 to the 203, but with good amounts of grease and patients, you can get them together.

The cross member of old is just that, old now! Your new and improved cross member runs across the top of the assembly and bolts to the 203/D20 adaptor. It uses the same cross member perches that the old cross member bolted to and the kit supplies bushings for this area.

Shifters…………

There is a new D20 shifter mount. It now bolts to the top cover of the 435 using supplied bolts. The new shifter site about 4 inches back from the previous position that mine used to site in. HOWEVER, yours may differ because mine was not stock to begin with.

For the 203, when you get your 203 from the donor vehicle there should be a Z shaped bracket on passenger side of the gear redux box. WH supplies shifter for both the D20 and the 203. The 203 shifter, I welded to the Z bracket and then bolted it the shifter mount. Unfortunately I didn’t take any pics of the modern art master piece but it’s described well in the direction.

Measure positions, and cut as necessary your floor board to accommodate all of these neat things and you are just about at the end of the project.

The kit lengthened my driveline a bit over an inch, but my driveshafts were able to absorb this with no mods. Your call on yours!

If you have any questions, I am glad to help.

by Mike Mussett

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