Engine/Transmission (1994 - 1998) differences between 2wd and 4wd NV4500

[Will24]

Can anyone give me a quick rundown on the differences between 2wd and 4wd NV4500s? Is the main shaft the same? I have a chance to get a free 2wd trans that would allow me to get my 12valve back on the road, it's been parked due to money etc for the last year. Any thoughts?



Thanks!

Will

 

[Joseph Donnelly]

4WD has a shorter mainshaft and different tail housing. You should get the fully splined mainshaft kit, and probably the small parts kit for the snap rings etc. from a vendor like Standard Transmission & Gear (800-std tran), so just get the 4wd mainshaft kit and use the tailhousing you have. Or, better would be to get the heavy duty iron tail housing from them. I have seen the stock aluminum tailhousing crack and leak out all the lube before the driver knew it. The trans then welds itself into a boat anchor. If you get both items, you can have the new trans ready to install before you turn a wrench on your truck.

 

[Will24]

Joe, thanks for the reply. I actually have a 48RE sitting on my garage floor that will eventually wind up in this truck. at 190k miles, this is the second 3rd driven failure I've had in NV4500s. Obviously due to the shaft layout, 3rd gear puts the most stress on the shafts, but without any real NV parts available any more, I don't trust putting import gears in this thing. If I can only get 30k out of a $3000 NV4500, I can't imagine the imported parts lasting even a fraction of that. I figure at least main shaft, snap rings etc, plus the thrust bearing for the head gear (the SBC input shaft and unsprung clutch seem to eat those bearings alive, plus the added stress on both shafts... )





We'll see what happens, right now putting an NV back in again seems to be the most cost effective way to make the truck driveable again. I am still hunting for a beat parts truck for the rest of my auto swap parts though, which seems to be the final answer, a built auto should be able to take 10x the abuse an NV takes

 

[SRath]

Is that fully splined mainshaft kit I see so many places selling a knockoff of Quad 4x4's design?

Will, you are one of the few guys I have ever heard speak of the 48RE as being stronger than an NV.

 

[hsmith]

Man, if you are only getting 30k out of the NV 4500, something is really wrong. I tow kinda heavy and had my first overhaul at about 175k.

Don't remember the link, but someone had new 4500s, not remans, for $2k. Just saw it yesterday. Will look back and try to find.

 

[Will24]

Trust me, the truck sees serious abuse, I will admit that. I tow heavy, I drag race, I sled pull and I tend to drive the truck in a fairly spirited manner. Couple that with running 3 times the rated torque through an unsprung clutch, and it's a recipe for disaster.

I do firmly believe that the 48RE is stronger, but not in stock form. Have you ever seen upgraded parts for an NV4500? The fully splined main shaft isn't a strength upgrade necessarily, it's a failure prevention upgrade. You can buy billet shafts etc for the 48RE, there is a MUCH larger aftermarket support network on the auto. I literally have got over $8k in transmission and clutch parts in the last 70k miles. I could have built a SERIOUS auto for that coin and the truck would be at least a full second quicker in the 1/4, plus, I would enjoy the truck a lot more.

That's my thoughts at least...
Will

 

[hsmith]

OK, Will, I get your point. I don't beat mine and mostly drive with a feather foot. On top on that am probably a bit fortunate with no frequent down time.

Smitty

PS Mine will haul butt, just don't push it while towing.

 

[SRath]

If you do all that, you need to look into a transmission from a semi. A 7 speed at least or maybe even go to an eaton 10 speed if you have a source of air for the range shift. Seriously. That dodge slushbox automatic won't hold up any better than the NV4500 under those conditions.

At the very least, if you are dead set on an automatic, I wouldn't waste a dime on a mopar transmission when you could probably put in an Allison just as easily and maybe even for the same money as all the aftermarket stuff the dodge auto will require.