79 f/w axle swap-want to do it right, not twice

I've reached a point where I must start a full width axle swap, probably sooner than I expected. I own a 74 Bronco w/stockish axles. 4.10 gears, Detroit Locker in rear, F-150 disk brakes, tie rod & drag link up front & Mile Marker hubs, but otherwise stock. Brakes are in good shape, font & rear. Recently, I bought a 79 Bronco & took the axles. I know they aren't the best choice, but I got it cheap (3.50 gears, open, both front & rear). I broke my right front, axle u-joint & hub, last weekend. The installation of the new u-joint was difficult (ends of outer shaft mushroomed)& the joint does not run very smoothly. It drives ok, I tested it lightly Friday, but I don't have much confidence in it. I don't want to sink anymore money into my stock axles, but I don't have the money to build up the full width axles the way I'd like, right now. So I'm going to have to do this cheap and fix only the glaring problems with the f/w axles, overhaul the rear brakes, swap my front brakes, wait on gears & lockers. I've been power reading, hoping to learn enough to do the axle swap right the first time. I will pay now to buy the right stuff, so that future upgrades won't involve taking new stuff off & upgrading again. Please, if I'm missing something or you can point me in the right direction, any advice is appreciated.

I'm going to drop the money & buy a new set of extended radius arms. I have a 3.5" Duff lift & 33's, installed 13+ years ago. In the foreseeable future, I don't expect to add more suspension lift, just a body lift for EFI clearance. I want to end up running 35's. I will be using this truck to crawl, but also as a hunting rig & dog transport, so some highway use.

I've seen extensions from 6" to 12". What is the minimum extension needed to install the f/w axles without relocating the c-wedges? Are there radius arm frame mounts that will install with some extra angle to "point" the radius arm towards the new, wider axle mounts? Or should I just plan on installing them, "pointing" in the stock direction? With just a 3.5" lift, how much radius arm extension is actually useful to add suspension articulation? Wouldn't a 5" lift gain more from longer radius arms than my lift? My idea is that the longer spring, in the bigger lift, could droop more than my spring. The question is largely just for curiosity, since I'm probably going to go with one of the longer arms. Should I expect to need a new, longer, driveshaft, or shocks? My brake line & shocks are already longer, due to my 3.5" lift. Would the high pinion take up some of the need for a longer front driveshaft?

Can someone post links showing how the upper or lower front spring perch is relocated to keep the front springs straight? Does moving the lower perch inward cause interference with the lower track bar mount? The pic I saw showed the lower perch/mount sitting over the top of the track bar mount. But it seems much easier to fab a new lower perch than moving the upper bucket.

Now, I'm running an adjustable/shortened F-150 drag link/tie rod & stock track bar w/frame drop bracket. Since I'm going to do this on the cheap right now, I think I'm going to have to shorten the 79 Bronco drag link & track bar (I also have a tie rod/drag link & axle set, from the truck I got my current front brakes off). How much longer than stock can I expect the new linkage to be? Has anyone relocated the lower track bar mount, inward on the axle housing & used the stock track bar? I'm not sure what that would do to suspension geometry/articulation. Later, I'll upgrade & do a tie rod over swap.

Hopefully I'll be able to do a locker, new gears, & overhaul the bearings by next summer when I start trail running again. I just hope my current axle/u-joint doesn't shell before, or worse during, my hunting seasons. I'd like to start this swap around T-giving, if my junk lasts that long.

Thanks

Chad

you can't relocate your c-wedges because you have the cast wedges. you can run whichever length extended radius arms you want. the c-wedges point inward pretty sharply so tht isn't the issue. the only thing i've heard of people not likeing is that your lower spring cups sit a little further out than stock, making your coilsprings bow out a bit. wcb builds the uppers outward when they do the swap but the folks at duff just run them as is and don't have any problems from what they've told me.

3.5" of lift isn't very much for a hp44. if that's all the lift you plan on running then you need to make sure you set your bumpstops up before anything hits.

While your right a 5in lift gains more from longer arms than a 3.5in will it all depends on if your current setup is limited by the arms or not. In most cases I would say you only gain a little with longer arms and 3.5in lift but I would go with the longer arms anyway as you have to move the rear mount so it may as well be for the longer arms.
driveshafts should stay the same as usually you wont gain much flex over the current 3.5in setup and if anything your better off because of the HP axle. As for shocks its hard to say but you might want to run different upper mounts as well so you can run longer shocks.
As for spring mounts you have to mod what you have or just run as is it mostly just a matter of cosmetics anyway. No real limitations or issues with having the springs bowed a little.

Typically there's around a 3in differance in drag link lenght. I'd probably just convert it to a adjustable type so you can shorten it and have some adjustability. As for the trac bar well you could just shorten it the needed amount for now reweld it and maybe sleeve it for a little added strenght,

What they said. I have three rigs with HP44s..all are 5.5" lifted. One has stock arms..the other two have arms that are 14" longer than stock.

I realized that the c-wedges were not removable before I bought the truck. I thought about scrapping the housing and looking for an earlier model, until someone told me that the extended radius arms would work.

Thanks for the info. I am running a Duff Super Hoop so I've got taller upper shock mounts. I wouldn't think that leaving the shocks in the current upper mounts and using the new wider lower mounts would be a problem. I think when I'm ready, I can relocate new shock brackets off the hoops where ever/how high I want. I'll have to loose the shock mounted to the front of the radius arm cap when I flip the tie rods. I also may be able to gain something from the extra room when I install a body lift, if that helps.

How hard is it to get the upper spring buckets off, and relocate them out? I looked for the WCB part, but it doesn't show up on the web site. I'm not taking the body off & with no body lift, the space is limited. I'm very much leaning towards moving the lower springs over. Its nice to know that I can fudge it and run it as is, but I'll end up moving it eventually.

What taps does it take to thread an adjustable sleeve on. I live in a small town with limited resources, but I work at a GM dealership body shop, so many tools and tons of knowledge is readily available. I would also have access to a pretty advanced machine shop if needed. Plus I get to write off tool purchases, so if I have to buy a tap or two, thats ok. I've got 2x F-150 drag links, so if they are both good, I've got a back up. Would those same taps work to make the 79 track bar adjustable? The parts are at work & I don't have them to measure.

Thanks
Chad

Chad were theres a will there's a way. So far you got some good info. I'll Add some pic's of my 44hp.I made some brackets to move the lower spring cup in. Do you have headers? I changed from long tube to shortys for more room. The front drive shaft worked with no changes. I'm running 3 1/2" lift and 2" body lift. Also made a set of Lar's bars that are about 7-8" longer than stock.

Thanks for the pics. Your spring perches are the pics I saw. I guess the track bar bolts right up under your plate. I don't have headers now. Your long tube headers didn't clear the radius arms? Too bad if long tubes don't fit, but good to know.

Chad

Long tubes dont have an issue with the radius arms, they hit on the driveshaft. I run Cage long arms with a 44hp that I swapped in directly from a eb44. no mods on the coil mounts or shock mounts (Cage hoops). everything works fine. 3.5"lift will be tight on clearence with a hp under the engine. You will need a different track bar and draglink.

how to measure caster?

Things are moving along well, I think. For the front end, I've decided on buying a set of the Cage/Bloodyknuckle/Duff extended radius arms, will order this week. I'm going to build a set of lower perches to relocate the springs. On the rear axle, I've installed new brakes, axle bearings & seals, and pinion seal. I've also torched & ground the spring perches & shock mounts off. Now on to "freshen up" the front end.

I've been reading about caster & guess there is no way to predict what caster I'll have in the end. I've never checked my caster, just installed the 6* c-bushings sent with the lift kit. My truck is ok at highway speeds, but tends to wander. Tires wear fine on my tape measure alignment.

I have a Chrysler 300C AWD I'm going to lower some day. Since I'd lower the car for summer & raise it for winter, I'm considering buying this tool (to avoid alignment shop fees 2x per year):
http://www.speedwaymotors.com/Deco-Magnetic-Caster-Camber-Gauge,2698.html
Would it work on my Bronco, or is there an easy way to measure caster? I picture a bar running through the ball joint holes, before installing the knuckles. I'd rather measure it myself than pay a shop to do it for me.

Thanks
Chad

I wouldnt bother with the springs. With a stock axle they bow in a couple inches, with a FW, they bow out a couple.

I run 78/79 FW axles, with Duff (I think identical to the Cage Arms), stock coil buckets, my springs bow out a little. I cut my stock track bar, ground the OD down, slid it into some DOM and welded it up. I then used a heim on the axle side of the track bar with a weld in threaded insert for the heim. I found this process more time consuming but much cheaper than buying taps.

I have about 500 miles on mine with the springs bowed out and no problems. I swapped out my 5.5" suspension down to a 3.5, and do think my compression will be limited as the radius arms only have a couple inches to the frame, but with a high pinion axle my drive shaft will likely be into the exhaust first anyway.

Whats funny is I went FW to get the high pinion to fix my DS angle on the 5.5 inch lift, but with 3.5" of lift, I think I could go back to low pinion to gain the clearance on the DS. Sad thing is my D44 is new end to end with new 4.10 gears and an Aussie locker but I will likely pull it out to go low pinion and change my ratios to 4.56/4.88. Nothing like doing it twice
Dennis

dnewman9,

I've done most everything 2x or more to my Bronco.

I didn't consider driveshaft interference with the HP axle before starting this. Your news isn't good. What kind of exhaust/manifolds/headers are you running? Where is the interference? I have not changed my exhaust from when I bought the truck (stock manifolds w/pretty crappy dual exhaust).

Why did you change to a 3.5" lift? Do you still have your old 5.5" lift parts (would you sell them)? After this is all together, I know I may be rethinking lift height. I feel like there is a 50% chance of adding more suspension lift to make all this work right.

Chad

Chad

gunnibronco said:

dnewman9,

I've done most everything 2x or more to my Bronco.

I didn't consider driveshaft interference with the HP axle before starting this. Your news isn't good. What kind of exhaust/manifolds/headers are you running? Where is the interference? I have not changed my exhaust from when I bought the truck (stock manifolds w/pretty crappy dual exhaust).

Why did you change to a 3.5" lift? Do you still have your old 5.5" lift parts (would you sell them)? After this is all together, I know I may be rethinking lift height. I feel like there is a 50% chance of adding more suspension lift to make all this work right.

Chad

Chad

Click to expand...

I've got a HP D44 from a 79 Bronco under the front of my '71 with only 3.5 inches of lift but have fairly stiff coil springs in it now (yes they bow out). I've got a spare set of Cage 3.5 inch coils I'm planning on putting in it which are much more flexible. I hadn't thought about driveshaft interferance before reading this thread....DOH! I will probably put them on anyways to get more total flex and keep an eye out for any problems. I guess I can fix it with slightly higher bumpstops and still end up with more flex on the droop and be better off than I am today with very stiff coils.

broncotime said:

I've got a HP D44 from a 79 Bronco under the front of my '71 with only 3.5 inches of lift but have fairly stiff coil springs in it now (yes they bow out). I've got a spare set of Cage 3.5 inch coils I'm planning on putting in it which are much more flexible. I hadn't thought about driveshaft interferance before reading this thread....DOH! I will probably put them on anyways to get more total flex and keep an eye out for any problems. I guess I can fix it with slightly higher bumpstops and still end up with more flex on the droop and be better off than I am today with very stiff coils.

Click to expand...

Keep in mind I am running a 4.6 mod motor, but shorty headers and where my drivers side exhaust comes down and routes between the oil pan and transmission is the area of concern. I think this would be a problem with a windsor motor just as much. Fender well headers may fix the issue?
Dennis

gunnibronco said:

dnewman9,

I've done most everything 2x or more to my Bronco.

I didn't consider driveshaft interference with the HP axle before starting this. Your news isn't good. What kind of exhaust/manifolds/headers are you running? Where is the interference? I have not changed my exhaust from when I bought the truck (stock manifolds w/pretty crappy dual exhaust).

Why did you change to a 3.5" lift? Do you still have your old 5.5" lift parts (would you sell them)? After this is all together, I know I may be rethinking lift height. I feel like there is a 50% chance of adding more suspension lift to make all this work right.

Chad

Chad

Click to expand...

I just did not like the height of the truck for the use it gets. Plus with WH Gorilla flares and WCB fenders the 35's looked like 31s. I ended up trading my 5.5 lift for another guy here in towns 3.5 so no extra parts.
Dennis

Thanks for the info. I guess that I'll just deal with these issues as they develop. I hope that with the crappy exhaust I've got, the clearance won't be an issue. At least I feel like I know what to look for during/after the installation. Although, the more I read, the list of "unknowns" keeps getting longer.

How do the pinion angles & driveshaft length look with only a 3.5" lift? I'm still running my stock front driveshaft.

Has anyone kept a drop pitman arm & done a tie rod flip with the 3.5" lift? It seems that the tie rod would be very close to the bottom of the pitman arm. This would make the draglink closer to horizontal. Would this cause bump steer? other problems? I don't have my stock pitman arm anymore, it wouldn't come off the manual box I had to return for a core charge- we broke 2 pitman arm tools.

Chad

Chad
Look at my pic's again. I have WH 3 1/2" lift and 2" body. Also the tie rods are C 1tons with a flip. Steering bow is Toy power. Still working on the drop bracket I had the after market drop but it was to much. I'll be making my own as sone as the halfcab is done. We flexed it at work with a forklift and had no problems.

Thanks for pointing that out to me. These questions are hitting me at random moments.

What don't you like about the drop bracket in your picture? The track bar & drag link seem to line up well. I have a drop bracket similar that I installed with my lift.

When you reamed out the knuckles did you use a sleeve? Are there any good threads with these conversions? Seems the search function doesn't like short words like "ton" "tie" and "rod".

Thanks
Chad

That pic is the first setup. I should post a new pic. the drop bracket is a little close to the spring cup bracket I made. Also I changed the pitmen arm on the steering box to a 3/4" less drop. The new pitmen arm is up a little closer to the frame. I'll post up a new pic. tonight.

Thanks,

I'm reconsidering making the new lower spring perch, seems there are more people who haven't moved the springs, than have.

With the Chevy 1 ton tie rods, did you use a bushing after reaming the knuckle? Are the tapered studs the same size as F150 tie rod ends?

I'm asking because, I'm going to do the work at the body shop I work at, and want to get the truck mobile again in one weekend. I hate to have a bay tied up with my personal project junk. I can attack smaller projects as time allows, once the truck is mobile. If I could get a steering linkage set up & install it in the stock knuckles, I could flip it later.

Chad