What trans do I have?
 

My truck is a 1991 K2500 with a 454 engine. It has a 5 speed manual with overdrive. I was told that it is probably an NV4500, but all info on the net says that GM didn't start using this trans until 1992. My truck was built in 7/91 and uses a 92 front drive shaft, though. I found this out when I replaced the U-joints in it. Could my truck possibly have a 1992 trans, also?
The trans has problems. The bearings are noisy and it grinds going into 3rd gear. I am hoping to find a good used one, hence the reason for my question.
Also, I would like to go ahead and change the lubricant in it. I need to know what to use, depending on what trans it is.
Thanks!

Re: What trans do I have?
 

Another question. (sorry) Does the transfer case share the same lubricant as the trans, or does it use something else?

Re: What trans do I have?
 

I can't imagine what other 5-speed they would put behind a 454 besides the NV4500. It was probably one of the first.

You can crawl under it and get a pic. A pic of the shifter would lso help us identify it.

NV4500 takes a special fluid. So no, not shared with the transfer case.

Re: What trans do I have?
 

Look at the SPID tag in the glovebox. MT8 is the RPO for the NV4500.

Re: What trans do I have?
 

Usually a truck built after the halfway point of the year will go down a next year's model. Is your truck titled/registered as a 91? Chances are your suspision (sp) is correct.

Re: What trans do I have?
 

Yes. It is titled as a 91. The VIN also decodes as a 91.

Thanks. I checked and it is MT8. NV4500 it is.

What fluid would I use in the trans?
The transfer case fluid looks like ATF. Dextron II? III?
Thanks for the help, guys!

Re: What trans do I have?
 

http://en.wikipedia.org/wiki/New_Ven...0_transmission
Chrysler and GM sell a special gear lube for these tranny's. Castrol Syntorque is on the good list. If you can find it... It is not the same as Syntech so don't let the parts goobers fool you.