Turbo 350 trans trouble

Matsucorp · May 25, 2006

I have a 350 turbo trans bolted to a 350 motor in a 76 Jimmy, the tranny won't engage in park.

I can hear it clicking a bit as it rolls but it never engages (stops). Good thing the parking break works.

It has more miles than I care to account for but it runs pretty good.

It shifts fine, though sometimes it clunks downshifting while slowing to a stop.

Fluid levels are good, trans cooler works, I checked the linkage from the collar down to the input on the tranny, all fine. I got it earlier this year so hevan knows what the things been put through...though by the looks of it the previous owner was a fairly competent gearhead.

It's been going on for a few weeks now, the tranny is still working normally save for the hard downshift when rolling to a stop.

Is this a well known or common problem? I'm hoping it's something I can fix.

As with any transmission problem I fear the worst ($$$), but hope for the best.

I'm shopping for a rebuild as we speak, but if the problem can be addressed by the dropping of the pan, then I'm going in. Either way I got my work cut out for me.

Any insight would be awesome...

Thanks!

Matt

1998Z71 · May 25, 2006

I had a 76 Chevy Blazer with the TH-350 trans. The parking pawl was the culprit. The part isn't that expensive, can get from any dealer. Easy to change, too. Just need to drop the trans pan, you should be able to see it. If I remember right, it is towards the driver's side rear of the trans. There is a small plug on the outside of the transmission case that has to be removed. then the rod that the pawl is on can be slid out, swap out the pawl, slide the rod back in, reinstall the plug. Might as well change the trans filter as long as you have it open. All total, it took less than an hour to change it out. The part was less than $20. As for the downshift problem, not sure what could be causing that.