View Full Version : 1991 Chevy Truck 5 speed experts


f-body
08-20-2007, 11:35:11 PM
So I have this 1991 shortbed 1/2 ton 1500 series 4.3 V6 and 5 speed truck. Well the trans is making noise. And I know eventually its gonna need a rebuild. IS there a difference between the S10 5 speeds, the 1/2 ton 5 speeds or the truck 5 speeds that came installed behind V8 or V6's. I have the Getrag 5 speed or 85MM trans according to the Chiltons book.
Can I easily swap in another type of 5 speed?
What kind of limits do these trannys have as far as towing?
What other year truck 5 speeds will bolt right in with little or no modifications?

Any of you transmission experts please help out.

jakeshoe
08-21-2007, 02:36:54 AM
That is the NV3500 IIRC.
One piece case.
Don't tow in 5th, it kills the input cluster.
Some guys use a different fluid in it, thicker I believe to help the gear clash.
Different than the S10's, same on all the full size trucks, 4.3 or 5.7 AFAIK.

GetMore
08-21-2007, 10:11:19 AM
If you are looking to pick up a different transmission you will want to check prices before you make too many plans. The NV3500 is EXPENSIVE!

f-body
08-21-2007, 01:15:16 PM
hey Jakeshoe

(Wow a member form the original board)

So how much should it cost for a rebuild? I know you do autos do you rebuild manuals also?

What other 5 speeds will bolt right in?

I really do not tow very often but want to be able to.


What should I look for if I go the salvage yard route?

jakeshoe
08-21-2007, 01:36:30 PM
I don't really rebuild them. I don't have the spare parts if I need something and it's a hassle.

You can call around and get pricing on them, but look for one with a warranty.

I can check with my suppliers and see what a good one costs or a reman'd unit.

I don't know of anything else that will easily fit. You're stuck with that unless you want to do some custom retro-fitting.

You can tow with it, just not in 5th, you need to get back into 4th that way you aren't transmitting the OD load onto the input cluster, the mainshaft will be locked to the input in 4th (direct) and no load on the countershaft.

jakeshoe
08-21-2007, 01:41:10 PM
I can buy them rebuilt for $850 plus $200 core.

f-body
08-21-2007, 08:30:27 PM
Jakeshoe


What about a 5 speed with the granny gear like in a 3/4 ton or HD model? Its not much of a half ton tranny but would they hold up better. Will it fit in the half ton with a different crossmember or will big mids be required. I could always through a Richmond trans in it. OR use the long tail shaft TH350 auto in the camaro and get the richmond for the camaro. HMMMMM.


CHEVROLET TRUCK 3500 2500 TRANSMISSION NV4500 5 SPEED

http://cgi.ebay.com/ebaymotors/CHEVROLET-TRUCK-3500-2500-TRANSMISSION-NV4500-5-SPEED_W0QQitemZ160148248612QQihZ006QQcategoryZ33733QQssPageNameZWDVWQQrdZ1QQcmdZViewItem


or this one

Chevy/GMC 2500-3500 Transmission gas, diesel,2x4,4x4

http://cgi.ebay.com/ebaymotors/Chevy-GMC-2500-3500-Transmission-gas-diesel-2x4-4x4_W0QQitemZ130144556763QQihZ003QQcategoryZ33733QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

jakeshoe
08-21-2007, 08:52:15 PM
I don't know how difficult it would be. I've never done that conversion.
It may require a different floorpan or trans tunnel, probably would require driveshaft and crossmember mods, and definitely will require you to find a bellhousing and the associated hyd clutch parts.

http://cgi.ebay.com/ebaymotors/Chevy-GMC-1500-pickup-S10-NV3500-Transmission_W0QQitemZ130145982716QQihZ003QQcategoryZ33733QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

Stock trans has a one piece case, so the bell is part of the trans.

f-body
08-24-2007, 08:16:09 PM
Jakeshoe

What years had the same 5 speed trans as my 1991? How new a truck can I uses a similiar 5 speed from? I was considering using a 5 speed from a newer truck if its a bolt in or very easy to install. I know the LS engines are different and use a different bolt pattern.

I know I cannot use the 5 speed from a truck with the LS series engine like the 5.3 but what year did they start using the LS in the truck? I know it was 1998 for the camaro and firebird and 1997 in the corvette.

jakeshoe
08-24-2007, 09:04:06 PM
1999 was the last year for a conventional SBC in the trucks, but keep in mind there may be speedometer differences between a 91 and 99.
GM did a couple of different iterations of speedos in the 90s. Cable driven pretty much went away in the very late 80s, but they had a couple of different reluctor ring counts inside the trans.