NV4500 swap installed and rollin!

[yfs200p]

Originally Posted by kipps

I'll just add to this thread three years later--

If you switch between a sm465 and a nv4500, with both being 4wd, the crossmember and transfer case stay in the same exact position.

I know this is somewhat of an old thread, but can you confirm this? I have an 89 v30 with SM465 (shot) and NP205. I would love to swap to an NV4500 instead of rebuilding the sm465. I’ve read a bunch about it, but a little confused. How can I make them the same length, swap input shaft on the Tcase, put an adapter between them, both? I would love to leave Tcase in the factory position and not mess with driveshaft lengths. Thanks!

[kipps]

Originally Posted by yfs200p

I know this is somewhat of an old thread, but can you confirm this? I have an 89 v30 with SM465 (shot) and NP205. I would love to swap to an NV4500 instead of rebuilding the sm465. I’ve read a bunch about it, but a little confused. How can I make them the same length, swap input shaft on the Tcase, put an adapter between them, both? I would love to leave Tcase in the factory position and not mess with driveshaft lengths. Thanks!

I've never worked with, or researched, a np205. I don't know much about how they vary from the np208 in fitment. post #6 of the following link indicates that sm465-fitted 85-91 np205 are interchangeable with the sm465-fitted np208 cases. Also, the np241 and np208 are identical in fitment. By correlation, the 85-91 np205 "should" fit in place of the np241 which came behind the nv4500 from the factory.

https://www.pirate4x4.com/threads/sm...-np205.519198/

It appears you have one of the rare desirable 32-spline np205 cases with the round six-bolt pattern.

A nv4500 is virtually the same length as a sm465, if both are 4wd. There are slight differences of less than 1/2 an inch, but as far as I know, that's just manufacturing discrepancies over the years. It's not enough to cause any issue with driveshafts.

A potential issue is the transfer case shift linkage. The nv4500 never had the connection point for the transfer case shift linkage that the np205 requires. You'll need to fab up a bracket, or buy one. It appears that Advance Adapters makes, or did make, a bracket for that purpose.

Edit to add: be sure to look over any nv4500 good before installing it. Ideally even before buying it. Remove the shift cover, the pto plates, and the rear extension housing. Look for any debris in the oil, check for excessive slop in the input shaft/mainshaft combo, make sure there are no chipped or badly worn gear teeth, and confirm that the fifth gear nut and gear are still in their correct locations. It's also possible to tell the general condition of the synchros, just by looking at the spacing between the sychro teeth and the engagement teeth. I'm not well versed on that, though. I bought a 1997 nv4500 sight-unseen, and intended to stab it in and run it as-is. I opened it up, and found that fifth gear was half-way backed off, the input shaft thrust bearing was gone, the 3/4 synchro hub was trashed because of that missing bearing, the parts of that bearing had chipped two gear teeth, and the synchros were heavily worn. I'm facing $1000 in parts to get this thing back in operable condition. If I had run it as-is, it most certainly would have failed in the first 100 miles. These nv4500's are not hard to work on, if you have access to bearing pullers, a press, and basic fabrication tools for making some of the specialty tools required.

[SunSoaked]

Originally Posted by kipps

I've never worked with, or researched, a np205. I don't know much about how they vary from the np208 in fitment. post #6 of the following link indicates that sm465-fitted 85-91 np205 are interchangeable with the sm465-fitted np208 cases. Also, the np241 and np208 are identical in fitment. By correlation, the 85-91 np205 "should" fit in place of the np241 which came behind the nv4500 from the factory.

https://www.pirate4x4.com/threads/sm...-np205.519198/

It appears you have one of the rare desirable 32-spline np205 cases with the round six-bolt pattern.

A nv4500 is virtually the same length as a sm465, if both are 4wd. There are slight differences of less than 1/2 an inch, but as far as I know, that's just manufacturing discrepancies over the years. It's not enough to cause any issue with driveshafts.

A potential issue is the transfer case shift linkage. The nv4500 never had the connection point for the transfer case shift linkage that the np205 requires. You'll need to fab up a bracket, or buy one. It appears that Advance Adapters makes, or did make, a bracket for that purpose.

Edit to add: be sure to look over any nv4500 good before installing it. Ideally even before buying it. Remove the shift cover, the pto plates, and the rear extension housing. Look for any debris in the oil, check for excessive slop in the input shaft/mainshaft combo, make sure there are no chipped or badly worn gear teeth, and confirm that the fifth gear nut and gear are still in their correct locations. It's also possible to tell the general condition of the synchros, just by looking at the spacing between the sychro teeth and the engagement teeth. I'm not well versed on that, though. I bought a 1997 nv4500 sight-unseen, and intended to stab it in and run it as-is. I opened it up, and found that fifth gear was half-way backed off, the input shaft thrust bearing was gone, the 3/4 synchro hub was trashed because of that missing bearing, the parts of that bearing had chipped two gear teeth, and the synchros were heavily worn. I'm facing $1000 in parts to get this thing back in operable condition. If I had run it as-is, it most certainly would have failed in the first 100 miles. These nv4500's are not hard to work on, if you have access to bearing pullers, a press, and basic fabrication tools for making some of the specialty tools required.

$1000 in parts? I'm fixing to rebuild my spare nv4500 at about half that price from Allstate. I wouldn't buy a used trans without assuming it needs rebuilt. Although I got lucky on my current one I just installed but I was able to drive the donor truck before he pulled it.

[kipps]

Originally Posted by SunSoaked

$1000 in parts? I'm fixing to rebuild my spare nv4500 at about half that price from Allstate. I wouldn't buy a used trans without assuming it needs rebuilt. Although I got lucky on my current one I just installed but I was able to drive the donor truck before he pulled it.

I've been deliberating between torqueking parts and rockauto parts. I would save a bit by buying from rockauto, but I'd still have to order some parts elsewhere if I did that. Torqueking has everything in stock. The biggest share of that cost is the rebuild kit itself, at $500. The rest of the expense is in the oil, the chipped 51-tooth countershaft fifth gear, the input shaft with its chipped gear, the trashed 3/4 hub, and a few small bits that I'll need.

Torqueking uses better quality bearings than rockauto offers, and the bearings were what caused my issues in the first place, so I feel some obligation to install the best bearings I can. I really don't want to go back in to this transmission. I'll be welding the fifth gear nut and gear together, so that shouldn't be failing any time soon.

[SunSoaked]

Allstate gear has better quality parts. I refuse to buy Chinese crap anymore.

[kipps]

Originally Posted by SunSoaked

Allstate gear has better quality parts. I refuse to buy Chinese crap anymore.

From what little I can tell, Allstate gear appears to have the same offerings as RockAuto. Likely the same kits and the same prices. TorqueKing seems like the more reputable company compared to Allstate. They've established an excellent reputation for actually knowing these transmissions, and their bearings are a higher spec than others.

[doubleclucker]

Originally Posted by yfs200p

I know this is somewhat of an old thread, but can you confirm this? I have an 89 v30 with SM465 (shot) and NP205. I would love to swap to an NV4500 instead of rebuilding the sm465. I’ve read a bunch about it, but a little confused. How can I make them the same length, swap input shaft on the Tcase, put an adapter between them, both? I would love to leave Tcase in the factory position and not mess with driveshaft lengths. Thanks!

I have been there and done this on my thread and had 1.5" longer than what I had before . though i took out a sm465 /bathtub np205 and replaced it with nv4500/round pattern 205 with short input swap.

[kipps]

Originally Posted by doubleclucker

I have been there and done this on my thread and you will have 1.5" longer than what you have now .
https://67-72chevytrucks.com/vboard/...d.php?t=611566

https://67-72chevytrucks.com/vboard/...d.php?t=611566

I just read through your build thread. It's awesome!

Are you sure the extra 1.5 of length didn't show up in the t-case swap? I've had my hands on three transmissions simultaneously; a 4wd sm465 with the factory hydraulic bell, a 1993 4wd nv4500 with the factory external slave bell, and a 1997 4wd nv4500 with the factory internal slave bell. All three measured within a half inch of length from the engine block to the transfer case mating surface. The trans mount point was the same as well.

[doubleclucker]

Originally Posted by kipps

I just read through your build thread. It's awesome!

Are you sure the extra 1.5 of length didn't show up in the t-case swap? I've had my hands on three transmissions simultaneously; a 4wd sm465 with the factory hydraulic bell, a 1993 4wd nv4500 with the factory external slave bell, and a 1997 4wd nv4500 with the factory internal slave bell. All three measured within a half inch of length from the engine block to the transfer case mating surface. The trans mount point was the same as well.

Yeah I realized the difference and edited my post so as to not give wrong info.

[MalibuSSwagon]

I just went thru Larry's thread recently as I am planning a swap. Looks like the ticket is a late round pattern 205, with the early short 32 spline input swapped in. Then it should bolt up to a 4wd NV4500 with no mods, other than clearance for the shift rail. ORD can supply the input shaft.

ORD apparently also has a good twin stick shifter setup with brackets as well. Likely the path I will go as it's proven.

[yfs200p]

Originally Posted by kipps

I just read through your build thread. It's awesome!

Are you sure the extra 1.5 of length didn't show up in the t-case swap? I've had my hands on three transmissions simultaneously; a 4wd sm465 with the factory hydraulic bell, a 1993 4wd nv4500 with the factory external slave bell, and a 1997 4wd nv4500 with the factory internal slave bell. All three measured within a half inch of length from the engine block to the transfer case mating surface. The trans mount point was the same as well.

This is good info! Just what I was hoping to find out. So in theory, I could swap a short 32 spline input shaft into my round pattern 205 and the NV would bolt right up. And according to what you say, the whole setup would be within 1/2” of what it was with the SM465. The slip yokes should handle that. Other option would be to keep my 205 input shaft and run the AA round pattern adapter which looks like it adds about 1.5” in length. Then I would be into moving cross members and having driveshafts made. I wonder if the AA bellhousing is the same length as the GM one, I’m having a hard time finding a trans with a bell. I like the AA bellhousing for keeping the slave on the drivers side would be a plus. Thanks for the info. Now I need to find a trans... it’s like everyone wants them or something!

[SunSoaked]

AA sells new, rebuilt trans. You're money ahead going that route in the end...and a lot less headache.

[yfs200p]

Originally Posted by SunSoaked

AA sells new, rebuilt trans. You're money ahead going that route in the end...and a lot less headache.

I know, I know. I just looked on Summit: trans, bellhousing, clutch with tax & shipping- $3261. That’s going to hurt, but will definitely ensure I won’t have to touch it for a long time.