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NV3550 install best ever mod or a buch of problems after.

1970mule

Bronco Guru
Joined
Dec 20, 2007
Messages
1,515
Just wanted to get a feel of what those guys that installed the Nv3550 had to say about its' performance after some time on the road. did it do great average or just tank?
like I heard problems with install, later syncro gears go bad fast. noisy.
 

miikee73

Shadetree Guru
Joined
Dec 14, 2010
Messages
3,551
Loc.
Aloha
I haven't done it yet,but it's on my list. If I do I know who to call^^^^^^ Neighbor..
 

SHX669

Bronco Guru
Joined
Jan 9, 2009
Messages
1,997
I'm certainly happy with mine.
Did the install ,went for test drive , rechecked everything for tightness , clearance etc. - haven't had to touch it since {6 years ago}
Only problem I had with install was some of the bolts in the kit were too short and some of the washers weren't big enough in diameter - a pretty easy fix with a trip to hardware store.
SHX
 

jmangi62

Bronco Guru
Joined
Jul 28, 2013
Messages
2,476
Well I really like the fit of it,and it should be a huge improvement over the stock three on the tree,but I'm still a couple months away from finishing my restomod so I can't comment on the performance of it,but I think it will be great,it's brand new so all good :cool:
 
OP
OP
1970mule

1970mule

Bronco Guru
Joined
Dec 20, 2007
Messages
1,515
well, sorry I did not give that many options, anyone please feel free to elaborate. I just want to get a feel of how people like the NV3550.
 
OP
OP
1970mule

1970mule

Bronco Guru
Joined
Dec 20, 2007
Messages
1,515
You've provided few choices on your survey. You
need to ask about installer experience and the question... new or used.
There is a bunch of broken stuff sold on ebay.
I'm happy with mine. But I bought it new and have done a few retrofits.

hey I just noticed where you are i'm in Bellingham. I guess we are neighbors now.
 

904Bronco

Contributor
Bronco Guru
Joined
Sep 28, 2004
Messages
6,039
Loc.
San Martin, CA
I'm certainly happy with mine.
Did the install ,went for test drive , rechecked everything for tightness , clearance etc. - haven't had to touch it since {6 years ago}
Only problem I had with install was some of the bolts in the kit were too short and some of the washers weren't big enough in diameter - a pretty easy fix with a trip to hardware store.
SHX

A vast improvement... Some of the same issues with bolt length and other hardware. My tranny was used, but supposedly rebuilt... I had it gone through locally and they found a few things that were questionable. It is not a race tranny, cannot row up and down through the gears. I used the AA cross-member, it had Sh*ty paint that came right off. But a great fit.

Here are my notes:

• The fill/drain plugs on mine needed a 19mm allen to remove them. I made one out of a metric bolt with a standard threaded nut welded to it. Put a socket on that…
• Set the pilot bushing in as deep into crank as it will go to give you 1/8” – 1/4” inch more clearance. If you do not, there may be binding where the input shaft tapers back up in size.
• The pilot bushing needs to be soaked in oil overnight.
• I did not have to cut ¼” off the tip off my transmission shaft. I measures tolerances multiple times.
• I bench fitted everything together before putting the assembly in my rig. I put the transmission in first and then added the T-case.
• Buy an alignment tool for a 10 spline disk with a .75 inch diameter pilot bushing center
• I used a 164 tooth, 50 oz, 11 inch flywheel as I have a late model motor in my 77. I was told I could use a flywheel from an 87-91 F-series Truck with a 5.0. After I looked at a new one at NAPA (China), I elected to buy the one from WH which in made in the USA.
• I was told by my pressure plate supplier that the 76-78 trucks had a unique mounting bolt pattern for the pressure plate, most suppliers use a Chevy style bolt pattern which is more common. The WH flywheel was drilled for the unique pattern.
• I used silicon sealer on the flywheel bolts to the crankshaft; this is to prevent oil leakage and was recommended by my engine builder.
• I would recommend running a tap through all the threaded holes to clean up the threads. Do this in the bellhousing, transmission, mounting holes on the frame, etc. I used anti-seize or loc-tite on almost all of my bolts
• I bit the bullet and used the Chrysler trans fluid, you need 2.5 quarts to fill the transmission.
• I cut a 5 inch square hole in the center of the Trans hump on the body. It is a little larger on the driver’s side because of the existing transfer case shifter hole. I made a cover plate to screw down on the body over this hole as suggested in the NV3550 write up in the Tech section. In the front, I cut right up to the body support, but not into it.
• I cut an inspection hole on the driver’s side of the transmission hump with a holesaw; I then cut down the 5x5” piece I removed from the top to make a cover plate. This gave me access to the twin stick shifter mounting bolt.
• I used the twin stick boot from WH and I found a Hurst boot at AutoZone for the transmission shifter. The Hurst boot is mainly a dust/dirt boot, one day I will make a nice one like MarsChariot in the Tech write up. (Hurst # 114 7336, B1 boot and plate. Turn the plate over to not see the Hurst logo)
• With the 1 inch body lift in place, I placed the factory clutch rod next to the adjustable WH rod and made it 1 inch longer. This was my starting point for my clutch adjustments.
• I had to heat and bend (at the existing bend) my transmission shifter from A/A as it hit the dash pad. The first shifter from A/A did not fit my Trans, as mine had the square mount. A/A were very good to work with; they sent me the correct one and a return prepaid UPS label for the wrong one. They make 3 shifters, so you need to make sure to tell them what you have.
• The A/A NV3550 rear adapter now has 3 positions (threaded holes) for clocking the D20; you must use the center (factory position) hole in order for the WH twin sticks to work.
• I have a J-shift D20, the A/A kit is designed to work with the T-shift D20. With the J-shift you must use a twin stick set up. For my rig on the A/A T-case shifter mounting bracket: I had to drill a new hole ¾ “directly above the threaded hole A/A had put in their bracket. I then tapped that hole for a ½ x 13 bolt and used the pivot/mounting bolt that was supplied by A/A instead of the bolt that came with the WH shifters. (Same bolt, it just had the threaded end cut down.)
• With the A/A shifter bracket, I had to round off the top (shifter side) of the bracket for shifter clearance. Basically, 45 the corner instead of 90 degrees. I also had to notch the transmission case webbing just a little, near the top of the bracket support, for the proper fit.
• I had to heat and bend the twin stick shifters for clearance from the transmission shifter. This was done at the existing bends and it did not require a lot of movement.
• I felt most of the bolts supplied in the A/A kit could have been longer, there was room, I purchased longer grade 8 bolts and hardware. This was a personal choice and is probably over kill on my part.
• The supplied A/A crossmember was well built, but the paint was scratched up. I tried to do some touch up with some black Krylon and the factory paint lifted. A can of brake clean removed all of the factory paint and I repainted the crossmember.
• My catalytic converter had to be moved back about 3 inches, a short extension welded to the factory Y pipe and shortening the pipe between the Cat and Muffler.
• I ended up rebuilding my D20 so I upgraded with WH - HD output shaft. This caused me to have to shorten the rear driveshaft. When I got it to the Driveshaft shop I found out it was toast, so now I have a brand new one…
• Wiring: I had a C4 before my conversion and the neutral safety/reverse wiring harness went with the transmission to my neighbor. My 77 had a rubber 4 prong plug from the main harness to the C4 harness. Fortunately for me, I had another 4-prong plug in my box of junk. I wired the neutral safety wires together with this plug and extended wires down the transmission. I already had a GM Weather pack plug, which I wired up the transmission reverse light plug.
• I found, at least with my rig, that I cannot down shift the Trans into 2nd unless I am 20 mph or less. It grinds…
• The transmission feels good with 3:50 gears and 31x10.50x15 tires. RPM is around 1900 @65mph. I have a Carburetor now and I am looking forward to my EFI conversion this summer.
 

DirtDonk

Contributor
Bronco Guru
Joined
Nov 3, 2003
Messages
49,452
Still waiting to do mine, but of those I've driven and/or sold to customers, I have some feedback.
I'll address some of 904's observations first though, because I think they're good to know.

The pilot bushing is now a true roller bearing, so no soaking needed. Make sure it's got grease packed in it of course, but since it's not a bronze Oillite bearing anymore, the oil is not used.
The newer crossmembers are gold cad plated again. So no crappy paint to peel off (at least for now) anymore. Looking at one right now in fact.

Many people have had issues when initially mounting their transmissions getting the rear mount bolts to line up with the crossmember. Some are easily fixed with some tweaking, some are fixed with a little extra drilling. Some require more massaging than that though, and for that reason A/A is working on a new intermediate mount with either more holes, or slotted holes, to aid in aligning the trans with the crossmember. Each installation is different.%)

But you asked how people like the trans once it's in.
Confirmed that these are indeed noisier transmissions than a stock car-based Ford 303 series boxes. So those of you with bare floors and especially those with holes in their tunnels are going to hear more noises coming from that area. But if you hear some oddball stuttering and rattling noises, especially during shifting and coasting, then you should check your rear pinion angle. The harmonics of a mis-aligned rear u-joint will really set the trans to chattering.
Of course, you should be verifying your pinion angle always anyway, but this trans just makes it more noticeable when it's wrong.

Not like the stock shifting, but it's way better than old school truck transmissions. Fairly nice shifting, and much better gear ratio selections than the stock 3-speed, which almost NEVER had the right gear for me.

All of it's good features, size, gear selection, overdrive, "strong enough" are why I'm putting one in mine too.

Paul
 
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SHX669

Bronco Guru
Joined
Jan 9, 2009
Messages
1,997
Don't the "new " transmissions come filled with oil {it is a sealed tranny }?
My tranny was used so I changed the oil before install - make a "tool' to remove the drain plug out of a bolt with a "head" of the correct size/shape.
SHX
 

DirtDonk

Contributor
Bronco Guru
Joined
Nov 3, 2003
Messages
49,452
Don't the "new " transmissions come filled with oil {it is a sealed tranny }?

I wouldn't count on it. While we've found a few filled with oil, I don't think that's been the norm. I could be wrong, since I haven't asked that question in awhile, but that was how I remembered it. Guess I'd better ask again, just to be sure.
And no, they're not quite sealed, as you can easily pop the top off where the shifter is and fill it there.

Rule #1 though, is always check. No matter what trans or source!

Paul
 
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blubuckaroo

Grease Monkey
Joined
Jun 11, 2007
Messages
11,795
Loc.
Ridgefield WA
My son has a Jeep with a NV3550. It has over 130K miles on it and I'm embarrassed to say, it's never had the oil changed. If you take care and install it correctly, it should be very reliable.
Don't force the assembly. If it doesn't slide right in, something's wrong. They say the pilot shaft is sometimes too long. I've never seen it but be sure to measure before assembly. As DirtyDonk commented, it's more sensitive to pinion angle than the old tranny, so if you have a lot of suspension lift, be sure to get yours right.
We've had this transmission in our Bronco for several years and have enjoyed the heck out of it. I installed it in the place of the factory C4 when my new 4.11 gears wouldn't handle the speeds on the freeways in southern CA. Since then it's been cross country and pulled our camp trailer long distance without issue.
There has been some debate about the gear ratio selection for this transmission. Of course, tire size and use should be the main considerations but this transmission has some unique gearing.
First gear is pretty low. At 4.01, it's not low enough to be considered a "granny" but it's low enough that it may not be necessary at all on the street if you've selected a gear ratio that's too low.
High gear is another story. At .76 overdrive, it doesn't have near the overdrive that the automatic transmissions have at .67 overdrive.
I guess what I'm trying to say is it would be really easy to select a gear ratio that's too low for this transmission. Personally I like my overdrive to be just that. A highway gear.
 

SHX669

Bronco Guru
Joined
Jan 9, 2009
Messages
1,997
And no, they're not quite sealed, as you can easily pop the top off where the shifter is and fill it there.

Paul
Ya - that's pretty handy to fill it from the top -I filled mine after install and before buttoning up the hole in the floor - and that "special Mopar" tranny fluid IS pretty darn expensive. :)
I followed the instructions that came with the adapters and one of the "write-ups " about the install and had no problems with the install - except the above mentioned bolts and washers.
SHx
 
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