NV4500 LD or HD

[Richard2112]

There is a ton of information on trans swaps here and they all have variants of one sort or another. Peppered sporadically throughout those threads are tidbits of information useful to some reader, or not.

The intention of this thread is to consolidate some information on the nv4500 trans and the differences between the light duty and heavy duty models.

I understand, though I could be wrong, that the light duty is an easier swap if one is looking to put an over drive trans in their truck.

Does that imply that the heavy duty model (those made for diesel and V10s) could be used?

I also understand that if it possible there would be 'a lot" more work involved, though I have yet to see that "work" described or the term "a lot", defined.

Is it a matter of swapping input shafts, output shafts..etc.? Has anyone used the 4500 HD as a replacement for an sm465?

Consolidating some general info on the 4500 might be a good thing. Advise is always appreciated.

[b454rat]

No such thing as light n heavy duty in 4500s, sorta. The v-10 and cummins are same tranny, just have bigger input bearing n shaft. But regular tranny is same as GM, but inputs are interchangeable.....

[Richard2112]

Thank you. Is there a reason to use the smaller input shaft? I understand pilot bushings can be bored to accept the larger input shaft (.75?) although that may not be the limiting factor when swapping to a 4500 that came from a diesel.

My info is limited when it come to possible modifications.

[mongocanfly]

I put a nv in my 81 behind a 6.0 lq9 replacing my 350 and sm465..the only differences I'm aware of is the dodge input shaft is different from the gm.like 454rat says..they are interchangeable. And the speedo output..dodge uses the gear to cable drive..gm uses the electronic output...the ealier nvs have a issue with 5th gear ...never heard of ld or hd nvs

[Captainfab]

I have not heard of a light duty or heavy duty NV4500 either. The Dodge version of the NV4500 has the longer and larger diameter input shaft. I have seen guys make use of the longer Dodge input shaft by using/making a 1" thick adapter plate when doing a conversion utilizing a standard GM bellhousing.

[Richard2112]

This perhaps is why I'm a bit confused on these things. I try to do as much research as I can but eventually the waters get muddy. Here is an exerpt from a web site (link below), it is the fourth paragraph:

There were many changes made during the production of the NV4500; two main variations were the NV4500LD, which was used with Dodge V8s and GM gas and diesel engines, and the NV4500HD, which was used in Dodge trucks powered by the Cummins diesel and V10 gas engines. The HD (Heavy Duty) version was unveiled in 1994, and had an increased input torque rating of 460 lb-ft, thanks partly to a 1 1/4” ten-spline input shaft.

http://www.allpar.com/mopar/transmissions/NV45

Thank you for all the input and replies.

[Richard2112]

[QUOTE=Captainfab;7773776]I have not heard of a light duty or heavy duty NV4500 either. The Dodge version of the NV4500 has the longer and larger diameter input shaft. I have seen guys make use of the longer Dodge input shaft by using/making a 1" thick adapter plate when doing a conversion utilizing a standard GM bellhousing.[/QUOTE]

Yeah that's what I am considering. Don't think I want to go the route of hydraulic clutch and would like to widen my scope of options a bit. It is (somewhat) easier to find a nv4500 from a cummings or v10. Initially I thought these weren't an option in my case. But if the limiting factor is the input shaft, and that is either usable or easily interchanged, then it opens my options when trying to find a usable nv4500. In fact, it seems they might all be good candidates. Or perhaps, I'm still missing something, which is entirely possible.

I suppose that if I want to keep my stock bell housing I could swap out the larger input shaft for the smaller and be ok on the front end.

[franken]

I just used a GM 96 trans because it seemed the right solution. No need for a lot of extra talk.

[notchbackgta]

I'll trade you a GM input shaft for a dodge, lol. I already bought a GM 4500 trans out of an 98 (I think that was the year, it is the later one though) and I plan on using it behind a Cummins, so I will need to swap out the shaft anyway.

You can also buy the bellhousing from Advance Adapters to use the clutch fork style release instead of the hydraulic. I bought one for use in my C10 2wd and kept the stock linkage. I had some issues but it was because I was using a BBC not in the standard location and my bellcrank is at a funny angle because I was trying to figure it out and just used it like it was once it was in. I took a bellcrank from a SBC and cut it down and welded it back together.
Input shaft on the late is 10 spline, I was able to just stab it behind my stock clutch from my 307 using the AA bellhousing.

Also the early/late GM trans has a different 1st gear ratio and the mounting ears on the housing are different. The early has a 6.xx 1st and the late is 5.60 (I think that's it). Dodge is all the same, I think the same as the late GM.

[snj8198]

The early has a 6.xx 1st and the late is 5.60 (I think that's it)

yep, 6.34 vs 5.61. Second gear is slightly different too. The wide ratio was used til 1994 then the narrower ratio was used. I prefer the narrow ratio for daily use and towing but the dedicated rock crawlers and trail dudes prefer the wide ratio for that steeper first gear. I have a '96 and up in mine. I use low range in the np205 for trail needs (1.94:1).

[Richard2112]

Ok, after spending many late nights staring at the pages of the web til my eyes bleed, looking for the most appropriate nv4500 with all the desired bells and whistles, within reach of my location and in an acceptable price range I have finally acquired one, which if not exactly the perfect choice at least provides me with a rebuildable core.

It seems to be from a 93, GM 2WD something and has the 1.125 ten spline, .590 input shaft, 5.125 front bearing index, fixed yoke, and the transmission to bell housing bolt pattern that differs from the SM465 that I plan on replacing.

I am planning on either:
1) using this as a core for another trans OR
2) rebuilding this one with some modifications.

I would prefer to rebuild this one but not dead set on the idea if a better option is available. That decision rests on some information that seems elusive and concerns the ability to swap a dodge output shaft for the one that's in the GM trans. My interest in doing this is solely for the purpose of retaining my mechanical speedo.

My understanding, limited as it may be, is that the Dodge and the GM 4500s are the same internally. I do not know if that means they are basically configured alike or the internals are interchangeable.

Would there be any difficulty in using a Dodge output shaft with a speedo drive gear and using that in place of the output shaft that exists in the trans?
Or perhaps there is a better mod that allows me to use my mechanical speedo??

Thank you for the advise.

[mongocanfly]

The input shaft is what needs changed...Swapping inputs from dudge trans to chevy inputs for the mech speedo is not uncommon.I looked into that but couldn't come up with a donor trans just for the input shaft..that's why I went with the dakota digital convertor and my chevy trans...to keep my mech speedo in the dash

[Captainfab]

How does the input shaft have anything to do with the speedo gear being electronic or mechanical. I have heard of guys using the longer Dodge input shaft so that they can use an adapter plate to mount the NV4500 to a standard GM bellhousing.

Originally Posted by mongocanfly

The input shaft is what needs changed...Swapping inputs from dudge trans to chevy inputs for the mech speedo is not uncommon.I looked into that but couldn't come up with a donor trans just for the input shaft..that's why I went with the dakota digital convertor and my chevy trans...to keep my mech speedo in the dash

[mongocanfly]

Here goes..changing the input shaft has nothing to do with the speedometer. Its the dodge transmissiin that people are after
the dodge nv4500 trans has a mechanical speedometer output shaft but has a longer input shaft
The Chevy nv4500 trans has the electronic pulse speedometer output shaft but has the shorter input shaft..
when people want to keep their mechanical speedometer they are using the dodge version nv4500 and swapping the input shaft from a dodge to a chevy..
Doing this is giving them a chevy style input nv4500 with a mechanical speedometer output.
When I did mine all I had was a newly rebuilt chevy trans.my only option then was the dakota digital convertor which takes the chevy speedometer electronic pulse and converts it to a cable drive so that I could keep my factory speedometer

[Richard2112]

Originally Posted by Captainfab

How does the input shaft have anything to do with the speedo gear being electronic or mechanical. I have heard of guys using the longer Dodge input shaft so that they can use an adapter plate to mount the NV4500 to a standard GM bellhousing.

This is yet another thing I have been considering. I have read that one can actually drill and tap the front of the transmission to bolt directly to the bell housing and avoid using the adapter plate.

Since my NV4500 input shaft has the same specs as my SM465, I'm not seeing where this would cause problems. Admittedly, this is a first for me and there are many things I have yet to discover, but it seems logical that drilling the trans case would keep all the linkage geometry the same such that it would ease the swap considerably.