The Stovebolt Site Forums The Parking Lot '60-'66 Trucks NV4500 swap

I have seen a thread about this, but didn't answer my questions. Would it be possible to run a manual clutch and SM420 bellhousing on the NV? I am going to get one from a 1 ton 2WD Chevy with either a 350 or 454. Are there any spline differences on the input shafts? It is going in a 283(HI-TORQ), and want to make sure it will mate directly up to this engine, no adapter plates. If I need to have the hydraulic clutch for it to fit, so be it. I was just wondering. My 64 is geared nasty as it is(super-low 1st, 5.14:1 rear end) and does 55 in 4th at about 3000 RPM with half the pedal left. Overdrive is my main benefit here.

yes and no to your questions.

Can You run the sm420 bellhousing... yes, but you need a 1 inch adapter plate, and the dodge nv4500, or at least the dodge pilot shaft and bearing retainer collar. There will be some extra machining involved on the Advance Adapter plate as the one they have for a gm bellhousing is indexed for the later 5.125 inch bore bellhousings. The Sm420 bellhousing is indexed to 4.686 inches. The indexing lip on the adapter plate can be cut down to fit, or if the bellhousing is out of the truck it can be bored out to 5.125.
The Dodge standard duty NV4500 and the gm NV4500 use the same spline count which is 10 spline on 1 1/8 inch shaft, which should be the same as in your truck now. There is a HD dodge version that went behind the diesels and the v10s that had a 10 spline 1 1/4 shaft. This transmission can be used if you swap out the bearing retainer and the pilot shaft for the regular duty dodge NV4500.
There are companies like "High Impact" that might be able to design a kit for your install. http://www.high-impact.net/transmission_and_gear/nv4500.htm

The 1994 -1997 Dodge 2wd NV4500 is the most popular for an early chevy swap for a few good reasons.
1. The mechanical speedometer will work with this incarnation of the transmission.
2. Most of the stock clutch components can be used. I spun down the collar on the bearing retainer on a lathe so it would accept the stock gm throwout bearing. There is a crossover throwout bearing for the swap that does not require machining the collar. The Pilot bearing will need to be ordered speacial or fabricated. The gm transmissions have a pilot tip that is .590 inches. The Dodge pilot tip is .750 inches.
3. The dodge transmission will work flawlessly with a 1 inch adapter plate because the pilot shaft is 1 inch longer than a chevy pilot shaft. The adapter plate is prefered when the bellhousing mounts to a crossmember. You will not have to change motor mount setups this way, or clutch linkages.

Can a gm NV4500 work in your truck? probably, but you will have to figure out things like new motor mounts, speedometer hookup and new clutch linkages.

For the record, I have not done this swap on a 60s vintage chevy. I have done it on a 1959 gmc that had an sm420, and a 1940 gmc with a 6 cylinder.
John

Which adapter plate from advance adapter? I don’t see this adapter on their website and would like to have a little more info before I called them. Bellhousing bolt pattern?

I just bought a piece of 1 1/4" plate and took it to a machine shop. They made the adapter plate in less than two hours on a lathe and a drill press. They are pretty simple to make if your machinist has a little bit of experience.

Here's a link to the thread that shows mine NV4500 into 1963 c10

This is the adapter plate that was mentioned NV4500 adapter plate

You can use that adapter plate without any machining if you get you an early sm465 bellhousing. As previously stated, sm420's used a 4 11/16" bore bellhousing. The sm465 used a 5 1/8" bore bellhousing. The early sm465 bellhounsings were cast iron and had the angled mounts just like our sm420 bells, but they had that 5 1/8" bore that you need.

If you pick up one of those earlier sm465 bellhousings and swap it in, everything will be bolt in.

Good info! But just to confirm. The bellhousing still has to be bored out to 5 1/8” regardless of if you buy the adapter plate or make your own if you are using the sm420 bellhousing?

No, don't bore out your bellhousing.

If you want to keep your sm420 bellhousing that has the 4 11/16" bore, take your parts to a machine shop and get a custom plate made like I did.

I did not bore out my bellhousing. I took my bellhousing, and the whole nv4500 (after swapping the input shaft and front bearing retainer to the Dodge gas parts) to the machine shop, and told them I needed 1" of space between the transmission and the bellhousing (I brought them a 1.25" thick plate so there would be some metal to protrude into the bellhousing bore), and I needed one end of the plate to fit the 4 11/16" bellhousing and the other to fit the Dodge bearing retainer (I forgot what the diameter of the retainer was). They drilled and tapped the holes for the bellhousing as well as the transmission, and viola! perfect fit. [img]http://67-72chevytrucks.com/vboard/attachment.php?attachmentid=1205117&stc=1&d=1390588516[/img][img]http://67-72chevytrucks.com/vboard/attachment.php?attachmentid=1205118&stc=1&d=1390588521[/img]

Otherwise, the simpler route is to just find a cast iron sm465 bellhousing (already has a 5 1/8" bore that the advance adapters plate requires and will mount to your crossmember and motor without modification) and order the advance adapters plate.

Also, I used the GM nv4500 because I wanted the shortest length possible (the dodge versions tailshaft is super long). You don't have to change your motor mounts to use that trans. It just hangs off of the back of your adapter plate and bellhousing like an sm420 or sm465 or one of the old clarks. I just bought the Dodge gas input shaft and front bearing retainer which are one inch longer than the GM parts. I also had to get a different throw out bearing, but I used my old stock clutch and all my stock clutch linkage.

Lots of great information! I’ve been looking for the past several months for info on this subject and now I have the final piece to the puzzle. Thank you very much! I’m going to get the adapter plate made. I already found a guy to make it. 👍👍

Be sure to post up your results. The more information that gets posted on here the better

over on the 67-87 chevy truck website -there is a guy named -"lock doc" -leon russel - that did a nv4500 swap on a 67-72 chevy truck -it looks so simple -using no adapters -only a redrill & tap ?? but im thinking he used the rm 465 ? 67-72 bell housing ? if you cant find the article -pm me -he lives about a hour from me ! good luck mike

That's a good point. If you find a '93 or '94 GM NV4500, it will have a 5 1/8" bore which would match up with the sm465 bellhousing, and then you would only have to tap and drill some holes like you mentioned. The only issue to solve after than would be converting the hydraulic TO bearing if you wanted to keep manual linkage.

I just finished a rebuild on the NV4500 in my 93' K1500. The rebuild was just to freshen up the bearings , syncros and seals. It went pretty smooth even with having the transfer case involved. I was following this thread and believe that the bellhousing is much the same as the older style 60's GM's. as the clutch fork is on the right hand side. You may need to redrill and tap the mounting holes but that should do it. Speedway has a hydraulic release bearing that will work with the original bellhousing and will eliminate the clutch fork, it's not that costly around a $100.00.

if im thinking right ?? leon used the non hyd clutch ?? i need to find the site & reread it ! like i said i will be going to leons house soon -this fall & can ck it out ? im doing a 66 c-30 car hauler & would like to use the same trans -set-up ! thanks mike

Does anyone know which speedo gear I need in a nv4500 for a 235 Chevy? I have 4.57 gears in rear end.

Is the output standard duty or heavy duty for the dodge nv4500? I would assume standard duty but just wanted to check. Thanks