NV 4500 tricks or treats

[a5150nut]

My trans is leaking from booth ends, 4/3 syncro is gone and the usual clunks going on. It's been years since I have rebuilt a trans, so what are the tricks or quierks to these beasts?

I found a rebuild kit that has Brass syncros and at the least I need a new pilot shaft. (Bad bearing last time out) Replaced rear seal a while back between the trans and transfer case, still swapping oil. Are there any critical clearance issues, thrust washers to set, anything that won't be shown in the diagram?

Also, is there any recomended machining requiered? I wish I still had my magic looking glass so I could see into the future.......

And how bout the transfer case? This will be one busy weekend.........

[ogrice]

The most common failures for nv4500's are the overdrive gear cluster and the input shaft alignment/out of round/ thrust clearances. I had mine professionally built and the owner of the shop told me that if the trans was behind a dual mass flywheel that had clutch chatter, you can bet on replacing/ finding these problems:

input shaft excessive radial/axial play
first gear cluster shot
dummy shaft & bushings and bearings
overdrive gear cluster shot

Besides all of the bushings, bearings, and synchros he replaced the first gear, overdrive gear and the dummy shaft. Real costly fix, but had to be done. 1000 bucks. ouch.....

Hope that this helps you out.

[Inspector]

We had the trans rebuilt in the 93 a year or so ago. You will only know what you need after you crack the tranny. Ours needed the input shaft bearings, the counter shaft bearings and gear, all the sycrho clutches were worn. The output shaft splines were worn and so that needed to be replaced. Just to much for me to do so we took it to a trans shop that had experience with that big gear box. They did a good job with all that it needed and it works like new.
I would suggest letting the folks that have the tools do this job. No matter what it is a pricey rebuild but its worth it.
It all started with the output splines being worn so badly that the input coupling splines in the transfer case would slip while trying to get the mass moving in 1st gear. It made a heck of nasty sound so having to replace the output shaft anyway we had the marginal stuff replaced while the tranny was open just to save labor and parts later on. I replaced the planetary in the transfer case myself. There is nothing scary about a transfer case.
That trans is no light weight either. You will need alot of room under the truck to get it out and a good trans jack. It was just easier for us to have it rebuilt by a pro. We did remove and reinstall the monster ourselves though.
good luck.
Denny

[HH]

Check this site for some useful information, http://www.quad4x4.com/.