sm 465 question

[454k30]

You know I have heard that that problem is caused by a c-clip that flexes and allows it to pop out of gear. I was going to have mine swapped out with a pressed on spacer but when I pulled my gear box apart I found it was already put together like that. I guess sometime around the early 80's Muncie also saw this as a problem and fixed it. My father was the first owner of this truck so I know he never modified it, and I am the first one to ever get inside the transmission.

Maybe you could find a "newer" sm465 and swap mainshafts. Wouldn't even be that hard!

 

[Randy92782]

Well it's an '83 GMC and the transfer is a 208 so i'd imagine it's the newer of the 2. I have an older 77 model 465 and have no problems out of it

 

[454k30]

Huh? I wonder if its a GVWR thing. My 83 had a 205 attached to it from the factory.

 

[Randy92782]

Well it's a 3/4 ton ...?? Who knows. Maybe they switched it out over the years. It's kinda hard to believe cause it was originally my dad's work truck in the 80's. Back when it had the 6.2 diesel in it. The company bought it brand new and they pretty much kept it that way. they kept excellent upkeep on it and it still drives straighter than any other old chevy i've drove.

They sold it to my uncle who had since put an old 350 Goodwrench motor in it. That's when i bought it.