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-   -   NV4500 LD or HD (https://67-72chevytrucks.com/vboard/showthread.php?t=722923)

Richard2112 11-20-2016 12:46 PM

NV4500 LD or HD
 
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 11-20-2016 12:56 PM

Re: NV4500 LD or HD
 
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 11-20-2016 01:39 PM

Re: NV4500 LD or HD
 
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 11-20-2016 03:50 PM

Re: NV4500 LD or HD
 
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 11-21-2016 12:18 AM

Re: NV4500 LD or HD
 
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 11-21-2016 01:59 AM

Re: NV4500 LD or HD
 
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:

Quote:

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 11-21-2016 02:09 AM

Re: NV4500 LD or HD
 
[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.

'63GENIII 11-21-2016 03:03 AM

Re: NV4500 LD or HD
 
My NV is of the 1994 (early series) vintage with the lower 1st gear and the non syncro reverse. As far as I know, The newer generation cannot be retrofitted with the lower 1st gear and the older cannot support the syncro reverse either.

When I built mine, I was almost obsessed with the 5th gear nut issue. What I found (besides a myriad of "5th gear fixes" ranging from special nuts, specially hardened shafts, pins and set screws to tack welding the nut to the shaft) was that the majority of the fixes were aimed at the 4wd variations of the transmission that were subject to enormous torque loads... enter the turned up Cummins. Failure reasons ranged from harmonics to "the output shaft fretting" to crystalizing of the shaft itself. Personally I think that a diesel is going to transmit way more of the damaging effects of detonating its fuel through the crankshaft than a gasser would. Just my .02 there.

Now Im not saying that a Chevy can't lay down numbers that can damage a 4500. They can. Its just that getting a Cummins' torque output to double the rating of a 4500 has become as easy as falling off a log and they are doing so on a very regular basis.

The 2wd models seem to come in a short and a long version. My familiarity is with the shorter one. When I rebuilt mine, I noticed that the 5th gear nut on the short 2wd model was also holding the vibration damper and the fixed yoke on as well. Im not sure if that has anything to do with the lack of 2wd 5th gear failure reports but it is a difference worth noting. IIRC, the 2wd nut is also larger than the 4wd unit.

The newer units also used the "square top" shift tower as opposed to the earlier "round top" shift tower. Apparently the round can be converted to square if you know what you're doing. The advantage is smoother shifting as the round top style can be prone to dragging the shift forks and notchy shifting.

As far as LD vs HD versions, as mentioned by others earlier here, there are the larger interchangeable input shafts. I don't know much of these as I have the stock GM unit in mine.

One thing that is worth noting as Im sure you have read is the importance of the correct gear oil / transmission fluid. Mine came with regular gear oil in it and I didn't know any better. The syncros were gone before I made it to the end of the block. I have close to 10k on the rebuild that I did in the garage with no issues to date. Easy transmission to work on. Don't cheap out on the parts.

Richard2112 11-21-2016 03:35 PM

Re: NV4500 LD or HD
 
I appreciate the input from the members here as that has helped me to sort through the myriad of information. Also, the the discussion outside of a specific build/swap thread has helped to clear up some things.

My biggest problem with sorting through info is my propensity to over think things, amass way to much info and get lost sorting it all out.

This thread has helped to isolate the criteria I need to consider without taking into account those things that may apply to others specific swap/build and may have no real relationship to what I am intending.

In that way, the input of those here has been invaluable. I can now see those things that people were trying to share in their specific swap/build threads that ARE applicable to my circumstances, whereas before, I religiously took notes on every detail until I was simply swamped with too much information.

Thanks for the clarity and the opportunity to isolate those factors that are applicable and critical to my intentions.

The information on the square/round top trans was also very helpful and something I wasn't aware of previously. It came up as a question in my mind only yesterday and now that also has been answered before even asking!

Thus far I have been able to make the following assessments based upon the information:

If I intend to keep the stock GM bell housing, pressure plate and disk, then it is imperative that I also keep the same diameter and spline count of the input shaft. The length of the shaft may not be a problem as an adapter plate can be used to correct for distance. One inch I think is typical.

Since I am addressing a rear wheel drive circumstance, a fixed yoke output is almost a given. Also, the 5th gear retaining nut problem is far less likely to be an issue.

The year model of the trans is mostly limited by my desire to maintain the mechanical speedometer. Although I"ll admit here that I have my doubts about using a VSS equipped model and making a conversion back to the mech speedo, it might be possible during a rebuild. Don't know about that yet. Probably not possible or practical.

If I want improved shifting characteristics, it is advisable to change the from the round to square top during a rebuild.

The above (I think) is a basic limit of essential criteria that must be met to do as I intend for my specific purposes. And there is no realistic option to consider the nomenclature of Heavy Duty VS Light Duty. In the end, I get what works.:smoke:

mongocanfly 11-21-2016 03:57 PM

Re: NV4500 LD or HD
 
I used the gm version trans because of the extra cost and lack of parts to convert a dodge to gm shaft..on the speedo I used a dakota digital convertor to go from impulse to cable drive...works great but its extra cost..

franken 11-21-2016 10:42 PM

Re: NV4500 LD or HD
 
I just used a GM 96 trans because it seemed the right solution. No need for a lot of extra talk.

notchbackgta 11-30-2016 10:12 PM

Re: NV4500 LD or HD
 
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 12-01-2016 12:27 AM

Re: NV4500 LD or HD
 
Quote:

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 02-25-2017 03:15 PM

Re: NV4500 LD or HD
 
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 02-25-2017 04:16 PM

Re: NV4500 LD or HD
 
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 02-26-2017 01:09 AM

Re: NV4500 LD or HD
 
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.

Quote:

Originally Posted by mongocanfly (Post 7869386)
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 02-26-2017 10:15 AM

Re: NV4500 LD or HD
 
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

mongocanfly 02-26-2017 10:43 AM

Re: NV4500 LD or HD
 
When I did my nv4500 install I had several sites saved about doing the above modifications but I deleted them and can't find any of it now..if memory serves correctly I think the bearing housing needed machining as well..if I can stumble across them ill post them

Richard2112 02-26-2017 01:28 PM

Re: NV4500 LD or HD
 
I think I understand the idea of swapping the input, providing one has the dodge unit and want to bolt it to a GM bell and keep the speedo. I have an early (93) Chevy nv4500 with the speedo tone ring for VSS.

I am wondering if the inner/outer diameter of the tone ring and the inner/outer diameter of the Dodge speedo gear are close enough to swap even if some editing of the parts are involved. Or perhaps it is easier to swap the output shaft with the tone ring on it, to the dodge 2WD output shaft for the purpose of maintaining a mechanical speedo.

Since I do not have a Dodge trans to compare the two, I'm just assuming that the speedo gear (Dodge) is on the shaft in much the same position as the Chevy tone ring.

I would like to make this work because with all the reading and searching I have done, I've yet to see someone even suggest it. If I can edit the part diameters to fit successfully (preferably the speedo gear), that might be info worth sharing.

Richard2112 02-26-2017 01:36 PM

Re: NV4500 LD or HD
 
Quote:

Originally Posted by Captainfab (Post 7869837)
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.

'63GENIII 02-26-2017 02:51 PM

Re: NV4500 LD or HD
 
How much do the Dakota Digital Converters go for Mongo? May be cheaper in the end vs a rebuild and sourcing all of the Dodge part?

FWIW, I ended up using the VSS output for my fuel injection install. Speedometer cable comes off of the T Case although Im guessing that Richard is working on a 2wd?

Richard, what kind of shape is the 4500 you just found? Used with history, rebuilt or unknown? What are you working with for a bell housing?

mongocanfly 02-26-2017 03:23 PM

Re: NV4500 LD or HD
 
63gen..the dakota unit runs about $300.http://www.dakotadigital.com/index.c...rod/prd886.htm

mongocanfly 02-26-2017 03:31 PM

Re: NV4500 LD or HD
 
Here's the adapter plate..for dodge nv4500 to chevy engine.https://www.summitracing.com/parts/a...MobileSwitchNo

mongocanfly 02-26-2017 03:36 PM

Re: NV4500 LD or HD
 
Richard..drilling and tapping a dodge trans is not the answer..the input shaft on the dodge is longer than the chevy thus thats the main reason for the thick adapter plate.. you may be making it harder than it needs to be...keep it simple..

Richard2112 02-26-2017 07:03 PM

Re: NV4500 LD or HD
 
Quote:

Originally Posted by '63GENIII (Post 7870241)
How much do the Dakota Digital Converters go for Mongo? May be cheaper in the end vs a rebuild and sourcing all of the Dodge part?

FWIW, I ended up using the VSS output for my fuel injection install. Speedometer cable comes off of the T Case although Im guessing that Richard is working on a 2wd?

Richard, what kind of shape is the 4500 you just found? Used with history, rebuilt or unknown? What are you working with for a bell housing?

Well the 93 GM nv4500 is not a rebuild and I was told it needs syncros. But I wasn't planning on purchasing a used trans and installing it with out going through it anyway so a rebuildable core works just fine for my purposes.

I would like to use the bell housing that my sm465 is presently bolted to. And one way or another, I think I can. This 93 might bolt up to it but if it doesn't, I have seen articles posted on the net where drilling the trans case and tapping for bolts has been done. If that is viable for me, it would spare me the need to use an adapter plate (I believe) and my shifter wouldn't move quite so far back.

This GM trans that I have seems to have all the specs on the front (input shaft/bearing retainer) as my SM465.


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