Here we go again. I'm New to the site and have spent Hrs reading through old discussions on the topic. I've been shopping for parts and a nv4500 tranny. I've got a 92 W250 with just over 90,000 original miles ( second owner). The original owners pulled their 5th wheel down to Arizona and back to Washington State once a year then parked the rig until the next year. Seems they took good care of the rig. Too late to make this short but I've lost the tranny and I plan on changing the automatic out with the nv4500. Can I use a 2nd generation in my 92? Found a few I can afford but they state they only work in 95-2001 truck. Any help would be appreciated.

 

Yep it fits, but you either need the special bellhousing or do a complete 2nd gen swap including engine adapter plate, flywheel, and starter. It moves the trans back, not sure if you need to do any driveshaft alterations.

 

Thanks for the reply. I'll keep shopping and researching. Maybe someone knows of the best place to look for parts?

 

The 2nd gen swap...as stated you need everything from the back of the motor rewards. You might also have to slightly trim the inside edge of the drivers side frame rail by about 3/8 to clear the starter. Other then that it's a direct swap.

You will also need to either find a Getrag 5speed 29 spline NP205 transfer case, or convert your 23 spline auto unit to 29 spline.

 

Thanks!! huge help!! I'll keep taking notes and looking for parts

 

Are you dead set on a NV4500? You might want to consider a 47RH or 47RE conversion. Basically a direct swap for your old A518, tons better....from the reviews I've read. Be a lot cheaper, and easier to swap an auto for an auto.

 

The rear drive line shold need lengthened and the front shortened I don't remember how much. U shouldn't need to cut your frame for the starter

 

I really haven't considered another auto. I bought the truck because of the low low millage and sacrificed the manual. I'm not excited I lost the tranny but I'm thinking I'll take the opportunity to put in the manual. I haven't done anything to the truck yet so I guess this is were I start.

 

mwlu711
Your tag says 5 spd nv4500 used to be auto, best thing you've ever done. What results? The auto in my truck left me wanting some get up and go. Passing gear whats that?

 

Well I can say with my NV4500 I don't have a ton of get up and go. You can only shift so fast with these trannies. If you want a truck that will get up and boggie, then an auto is the choice.

Not trying to sell you on the auto, just giving you things to think about.

 

I've wondered why noone sells a conversion input shaft for the nv4500 into a first gen. I'm fairly sure that is all that would be needed to run it with the 1st gen engine plate, flywheel, starter and clutch. By the time you buy all that a new input shaft would probably be cheaper. A good machinist could probably even shorten the stock one I think it would only need about 1.5" cut off.

I agree my auto truck is a rocket from 0-60 compared to the 5 speed, 60 up they are about the same. Now if your planning on mostly towing the 5 speed is far better IMO. A good converter in the auto would probably improve its acceleration and towing though.

Also the auto swap to a 47rh needs the engine plate and starter off a second gen truck to go with it. The reason being the lockup clutch in the converter (46rh doesn't have one) makes the converter longer and they made up for the extra length in the engine plate not the trans case. I'm pretty sure this is the only reason an NV4500 isn't a direct swap also.

 

I am just finishing up a 727 to NV4500 swap. Besides all the second gen parts (block plate, starter, etc), some of the manual conversion parts (clutch hydros, pedals, clutch master cylinder support), and some basic wiring, there wasn't too much involved.

A few things worth noting:
1. I had to cut about 1/4" of the top edge of the frame rail for starter clearance.
2. I had to move the transmission crossmember back one hole, not sure if you will have to since your truck has a 518.
3. I made my own transmission mount, I used some 3"x3", 1/4" wall square stock, about 6-8" long. Drilled four holes and bolted it right to the rear of the transmission and to the 3/8" thick transmission support plate, that bolts to the crossmember using rubber isolators.
4. I didn't have to shorten the rear driveshaft any, but you might have to, just depends on how it looks after everything else is in place. I know the front shaft probably will have to be lengthend.
5. Transfer case. Find a 29 spline unit, or convert your 23 spline unit. That route you will need the 29 spline input shaft, large front bearing, bearing snap ring, and either machine out the front adapter to accept the larger input shaft seal and clearance for the input shaft bearing and snap ring. There won't be much material left to retain the seal, but enough with some loc-tite should hold it in place. One other option is to buy the 23spline to 29spline conversion coupler.

Hope this helps ya!

 

Yeah, you can't really shift the nv4500 like a sports car. 1& 2 are low geared. My truck really starts stretching it's legs in 3rd but I'm shifting into third before getting all the way through a normal Dallas intersection. It really rolls on in 4th and 5th tho. Can scare 100 in a hurry on the highway.

I have 4.10s and the 1st and 2nd gears felt very low with the 33s. The 37s really helped lengthen the gears some.

 

Well for starters my auto was wore out so fuel mileage was bad and not alot of power and towing with fhe truck was no fun at all .with the manuel tranny my fuel mileage increased by about 3mpg and towing power increased drasticly any way my preferance is manuel trans when towing with a diesel