Transmission mount (GM400) spring cups, 1 or 2?

I would imagine with the poly bushing it would probably be a lot tougher to move. I’ve got the ‘stock’ aftermarket rubber bushing.

What was is like getting the round edge washer started in the poly bushing before installing the sleeve?

Had to jack everything up a little so I could start nut. Then like you said, as i tightened, it fell into place.

I may try loosening nut a few turns, and use a jack to relieve pressure/move it around, maybe something got snagged?

Wait, you should have had to jack everything up, get all 4 bolts of the big plate started and turned in a bunch of turns. Then you can safely lower the jack, make any slight adjustments to the plate and snug up the 4 bolts. At that point the stud should be protruding from the rubber/poly bushing. Insert the round faced washer, followed by the sleeve spacer. Hold the big washer in place and put the crash plate in place and start the big nyloc. Bolt the front of the crash plate in place with its two nuts/bolts at the same time’ish. And finally torque the nyloc up.

Yep, it’s been half a year, so I forgot, but that’s how I did it.

Just checked, with or without nut tight, I can move it around a bit using the leverage from a screwdriver. So I think mine is good, the poly bushings are doing their job. I also bought a new spring, perhaps a bit stiffer?

I do get very nice hard/quick shifts with no slop from my B&M shift kit, so I think my trans mount is working fine. Previously before shift kit and mount, so much slop between shifts.

Yeah I’ve just done it twice in the last week so its ahhhh, pretty fresh to say the least. Fingers are still sore.

I did the new spring as well. I can’t move mine much by hand either, needs a little bit of leverage as well. What B&M shift kit did you go with?

I’m pretty sure my pump is sucking air on cold starts and causing moaning/groaning. I lost track of the O’rings during install and may have reused the old one at the top of the filter tube (in the housing) by mistake! So if I have to go in there for a 3rd time there better be a good reason other than my screw ups!

Supposed to use two orings now, it is recommended. Also, pickup is plastic and a $10 part. Worth replacing.

When I pulled my pan, I found out my 88 (87 TH400) had the dreaded pink plastic accumulator part, which eventually cracks and ruins the transmission. So I decided to pull the valve body (quite scary) to replace it with aluminum part. Since I was pulling valve body, I decided to get simple B&M kit, heavy duty stage.

88/89 was a transition year, so it’s very important to get the right kit.

So with just one rubber cup the ruble went away ?

Yes the rumble went away, or at least was very reduced.

Given how badly deteriorated my bushing was and the spring was probably original as well. What remaining noise I figure is just what my car naturally makes and the new bushing and spring mount is letting me hear it for the first time.

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