Mt8 = Nv4500???

[tkeduk8r]

Stopped by a yard i havnt been too in about 2 years and stumbled across a wrecked 93 4x4 city truck.. had a complete 6.2 and 5 speed with creep and od... is this the NV4500 (RPO MT8) and if so.. two more questions... would there be any difficulty sans hyd. clutch adaptation to swap into a 72 k20??? and what are these things worth or better yet what should a guy spend on one????i had seen a 71 complete with a front crossmemeber and disks and then i found this too... comments...
--Mike

[1969 GMC]

cool, that is one of the early NV4500's with the 6.34 first gear. iirc they only made them that way for a couple years.

i know a few ppl on this board have done the swap, it shouldn't be *too* hard to do.

[special-K]

Do it!

[vtblazer]

Originally Posted by special-K

Do it!

^^^ man of many words.

I agree though, sounds like a cool mod.

[FormerMember]

They're worth anywhere from 500-2000 depending on where you buy it from and it's condition.

Also depends on the junk yard. Pick and Pull in CA would hit you for >200.

Hydro slave cyl shouldn't be too hard to adapt with off the shelf parts. If you google it, there's quite a bit of info on these swaps.

Might even look at advanced adapters for information, as they have quite a few write ups.

[TravisH]

http://67-72chevytrucks.com/vboard/s...d.php?t=148231

[Americanrider]

The bellhousing pattern for 1993-1994 GM versions is unique from the later (1995-up) GM. The 1993 and 1994 Chevy versions have a lower first gear of 6.34:1 and an unsynchronized reverse gear. Transmissions after this period have a higher 5.61 low ratio and reverse gear synchronization.

The NV 4500 is a top loading five-speed transmission with a cast iron case, aluminum top cover and dual PTO ports. It features all helical gears, and is fully synchronized. The NV4500 has a case length of 12.37" and an extension housing length of 6.5". This housing contains fifth gear. As usual, 2wd style housings are longer.

A unique feature of the NV4500 is its fly-weighted 1st-to-2nd gear synchro assembly, preventing a downshift at excessive revs. Its unique synchro ring composition requires synthetic lubricant.

93-94 Gearing: 6.34, 3.44, 1.71, 1, .73, R 6.34

95 & up Gearing: 5.61, 6.04, 1.67, 1, .73, R 5.61

[tkeduk8r]

awesome info!!! but i cant remember if the speedo cable is in my 205 tcase or in the tail of the TH350... cuz ive read that the nv4500 has only provisions for the electric speedo connect... and one more question... the donor truck is one is a 4x4, but is there any length considerations to put one in one of our 4x4's since the engine is mounted further back???
--Mike

[Russell]

First of your concerns is the cost of bolting a 205 to the NV4500. The Advance Adapter is definitely not cheap... I think you can bolt an NP241 up fairly easily though, they can be found in the 88 - 91 4x4 burbs / blazers

The stock t-case is of no use to you unless you get yourself a Ford front diff. The IFS is driver's side drop on the newer Chevy trucks, while it will be pass side drop on your older truck.

However, switching to a pass side t-case presents a problem in itself. The 93/94 NV4500s have an external slave cylinder, cept on the pass side. So, when you put a 205, 241, or whatever onto the back of it, you could have front driveshaft to slave cylinder clearance issues.

The newer 95+ NV4500s have an internal slave cylinder in the bellhousing, so that is not a problem

I don't know if you are able to interchange the 93/94 and 94+ bellhousings though...

Personally, if I go NV4500, I'd want to go with a 93/94 2wd unit, then use my divorced 205 t-case. That would solve the front driveshaft to slave cylinder clearance issues.

[Americanrider]

"I don't know if you are able to interchange the 93/94 and 94+ bellhousings though..."

Nope, the have different bolt patterns on the face of the tranny. AA sells a bell that will bolt up and hook to a pre-86 SBC. $3-400 price range but you can use the standard style clutch.

http://eshop.advanceadapters.com/com...roduct_id=1665


Look for a long 32 spline input NP 205. This gear will stick out of the 205 case by about 3 1/2". This was used behind later model SM465 trannies and later TH400 trannies, from about '85 to '91 in straight axle 1-ton trucks. The NP205 yoour looking for has the round bolt pattern not the old figure-8. It will bolt right up to a NV 4x4 with a small adaptor to clear the shifter or you can have the case machined. They are hard to find and Pricey... about 4-600 and higher from a wrecking yard.

http://www.advanceadapters.com/catalog/042.html

See notes 13 & 14.