Getrag to NV3500

[smokeater05]

I have a question, can I bolt a NV3500 in place of my Getrag transmission? My truck is a 1989 with a 305, 1/2 ton. I have a first generation Getrag and the front bearing has come apart. I did not these were bad transmissions. I called two transmission shops to find out what fluid it takes and one said he was sorry for me and another told me I had a junk transmission. I have done research, but have not found much information about any one swapping transmissions. Some sites say the NV3500 are not that good either. I would like to put a NV4500 in it, but I think it would take alot more work. I found a guy in town who says he can rebuilt my transmission for $500, but if I can put a better transmissin in for a little more money, I would like to do that. If any one has any done this or can lead me in the right direction, it would be much appreciated.

[Winola73]

I thought the NV3500 WAS a Getrag.....

[smokeater05]

Getrag sold the design to new venture from what I have read. My window sticker for my truck says Muncie Getrag. I know it will probally bolt in, I just want to know if I can use my hyrdaulic set up in my truck or use the setup from what year I get a new venture from. This is some of the information I have found.

There are two designs for the input shaft on the getrag, input shaft bearings and main shaft bearings. The first design, which documentation will show as 1988-1990, had a ball bearing and a roller bearing behind it. The second design only has a ball bearing but it was a much larger bearing. The first design bearings were more prone to fail. They were failing when these trucks were under warranty with very low miles on them.

There are four design levels of this unit. It started as a HM290 found in GM trucks, and was re-designated 5LM60 with early and late designs. Hm290 and 5LM60 units each have 4 shift rails.

In 1991 it was referred to as NVG 5LM60
NVG= New Venture Gear
The 5LM60 has 4 internal shift rails is much more difficult to work on then the

1993 New Venture Gear releases the NV3500. Externally the earlier GM units "look like" the NV3500 however internal components were extensively re-designed.

The NV3500 uses a single-rail shift system, wherein all of the shift forks for all gears are actuated by single rail, as opposed to the three-rail shift system on many gearboxes. The single-rail system reduces complexity while providing enhanced shift feel.

[Winola73]

Well, I learned something new today. Have you tried cross referencing replacement parts listings for what fits what year? I'm 99.99% certain they would use the same clutch and I would say the same hydraulic clutch system. Look up the years the NV3500 was available and compare component listings for those years vs. your truck. You'll have your answer. It's worked for me for almost 40 years.

[smokeater05]

Thanks winola73. I looked up the parts on Autzone for a 1993 1500 and they are the same. I was able to get the transmission fixed for a $150 dollars parts and labor. I found a guy in Newnan that works on them. He replaced the front bearing and front and rear seals. If anyone eneds his number I have it, he works on 3,4,and 5 speed transmissions.