Engine/Transmission (1994 - 1998) What is the best NV4500 for High Horse Power Towing?

[BCriste]

I would like to get some feed back on what is the best way to build and/or modify a NV4500 for high HP, very high weight, long mileage towing? What is the best clutch?



Fact: I have a lead foot.

Fact: Highway average speed is 75mph

Fact: Total GCVW should be around 21k to 23k lbs.



I drive the truck about 20k miles per year empty, and I drive about 25k miles loaded.



My goal is to get real usable 350hp and 800ftlbs and build a transmission/clutch package that is as bullet resistant as possible.



Currently I have a Standard Transmissions rebuilt unit with 15k miles on it with a Luk clutch, which I'm planning on changing. The only thing I have added is a Geno's filter kit to one side.



I need to know what parts, and who sells them, I need to put the best combination together to meet my needs. Reliability takes priority over cost. AND NO I WILL NOT BACK THE POWER DOWN.



What I'm planing so far is:



1. ) Add a cooler to the other side of the transmission (Does anyone want to buy the other side?).

2. )Installing a Temperature guage

3. )Changing to a big Southbend Clutch. Looking for model suggestions. (REMEMBER, THIS IS A TOWING APPLICATION, BACKING UP A 44' TRAILER WITH A CHATTERING CLUTCH IS NO FUN AND CAN BREAK U-JOINTS AND SUCH. )



I read in one of the recent TDR issues about a 1-3/8" input shaft. Any feedback? Would this be a good idea?



Any other good parts to consider..... you know... . usually have words like "over-sized", "hardened", "billet"... ... you know what I'm asking???



Thanks again for the help. I would love to make this thing as "Bullet Resistant" as possible when I install the Clutch.



Brian Criste



By the way, The Truck is a 96' 3500, 3. 54, 2wd

 

[kentdiesel]

You have some good questions. I asked similiar ones when I put a fully splined mainshaft & SBC clutch in my truck. Talk to Peter at South Bend Clutch. They sale the 1 3/8" mainshaft and I bet he tells you that you don't need one for you application.



Ask Standard transmission if your rebuilt NV4500 has the fully splined mainshaft. IMO thats all you need internally. The fast cooler is probably a good idea. I would like to see some test data on how much they lower NV4500 temps. Run Castrol Syntorq oil.

Two phone calls should answer all your clutch and trans questions.



Thanks,

Kent

 

[Briar Hopper]

The fully-splined mainshaft is not the "cure-all" it is often assumed to be.

Less than 400 HP, you MIGHT be okay. At 450 HP, and without a load , I've shredded the inner teeth off the countershaft syncro clutch gear. THREE TIMES. Without a load, just by dropping the hammer in fifth. I've also broken the bolt heads on the thrust plate, and mushroomed the plate on another occasion, that was with towing an 8000 lb camper, and later on, a 14,000 lb. lowboy w/backhoe on it. Fifth gear just ain't for towing more than lawn mowers or a bass boat, or any hammering, no matter what anybody tells you.

4th gear at 65 mph is what you're looking at, not good for fuel mileage, lots of noise & rpm's... ..... Either a GearVendors over/underdrive, or a 6 speed might be your best bet.

JMHO, based on my own experiences, take it for what it's worth to you.

 

[RT66DOC]

I don't think anybody makes anything for the NV4500 that suits it for high HP/towing. Collect some info on conversion to NV5600 before you decide. Ask charlan - he converted his.

 

[BCriste]

.

Thanks for the replies guys. The problem with doing the NV5600 conversion is that my truck is a 2wd. From what I understand, the conversion is not possible because there is no way to hook up the speedo. On the 4wd trucks of the same year, the x-fer case has the provisions for the speedo. If anyone knows otherwise, I would love to know.



Thanks,

Brian

 

[RT66DOC]

Rats!



Sorry Brian, forgot about that. You are correct - need FWD for the conversion in a '96 from everything I've learned. You'd think one of our resident Bomb Genies would have figured a way around that but I sure don't know of any.



Well heck, whaddya really need a speedometer for anyway? You could get a GPS that would give you your speed. Remember, you're the one who said reliability over $$$.

 

[crabman]

???



Why can't you hook up the speedometer cable? Too short or what?

If it is to short, what about one from a later model truck?

Sorry if this sounds DOHHH but just trying to learn.

crabman

 

[BCriste]

Crabman,

I think ( Shouldn't do that too much ) it has to do with the older trucks being a mechanical speedo, and the newer trucks are electric. Don't know for sure. If anyone knows how to overcome this I would love to know.



Anyone know if someone has installed a big truck trans. Eaton Fuller, Road Ranger, Ect... . ???? That may be worth the work if its is possible. I saw some posts doing a search, but I didn't see anyone actually say they have done it and if so, how it worked (i. e. air source, clearance, shifter location, bell housing, clutch, ect... . ).



Brian Criste

 

[ewcmr2]

Re: Crabman,

Originally posted by BCriste

I think ( Shouldn't do that too much ) it has to do with the older trucks being a mechanical speedo, and the newer trucks are electric. Don't know for sure. If anyone knows how to overcome this I would love to know.

You could overcome this by installing a 4x4's nv5600 WITH the transfer case (the transfer case has the speedo sending unit hole). As an added bonus you'll get 2wd low for backing up a 44'gooseneck.



I looked into doing this but the parts cost was more than I wanted to spend.



Eric

 

[onestackdram]

BCriste- The big truck application has been tried and successfully so. It just takes a lot of modifications to do so. The problem is it's just not worth it. You don't end up with a 'better' final drive ratio than any of our 5 or 6 spds. ANd it cost's more to do the swap.

As far as what to do about your nv4500. You are really limited as to what you can do to make it better. The facts are this is a really POOR transmission. I would call Blumenthals in Oklahoma City and speak with them. They do the swap from 5 to 6 spds all the time. They will be able to tell you if it is possible on the 96. They told me it they CAN do it to my 97 Cab and Chassis. I just don't have the $$$$ right now.



Russell

 

[Bill Lins]

Originally posted by BCriste

What I'm planing so far is:



1. ) Add a cooler to the other side of the transmission (Does anyone want to buy the other side?).

I'll buy the other cooler if you go ahead with this.

 

[BudW]

My '94 had a choice of automatic transmission options. You had the 2*4, the 4*4 and the 2*4 with a PTO.



The PTO housing fit right in the place of the transfer case and didn’t do anything other than provide a couple of PTO mounts. It requires the usage of a 4*4 rear driveshaft though, but more importantly, it had the hole for the speedometer sensor.



I can’t remember the name but I think its number is NV021 or something like that.



This might be hard to find, but it will bolt to the rear of a 4*4 NV5600 using the 4*4 adapter.

I have a feeling that it will be more time/cost effective to go another route though.