I have a TH350 that I stripped down and completely rebuilt. New clutches, seals, bushings and pump rings. I also replace the stock valvebody with a full manual valvebody. All parts are from TCI and the rebuild went smooth. This is my second time tearing into one of these trannies so I had no problem putting it back together, everything spun nicely before I put the pump back together and then it got a little tight. When I was tapping in the new bushings some of the edges peened over just a tad and I think that is why it is hard to rotate when it is all together. Or mabey it's b/c I have to put fluid in it, I'm waiting to do that when I'm ready to start the engine though. But tonight I installed the driveshaft and I thought it would be easier to get it to turn by pushing the car back and forth in neutral. Well, it goes foward no problem but won't roll backwards very easily. It was me and a friend trying to push it at the same time and it's extremly hard to push. I had to get the car on the jack so I could roll it back to it's original position in my garage.
So if any of you trans speacialists out there would like to clue me in on what I did wrong feel free. In about a month from now I'll have my sidepipes and will be able to start her up, mabey getting some trans fluid running through her veins will help.

 

Look up 45ACP on this forum. He is a old tranny shop man.

Just off hand and I have not done that many auto trannies in my life, but I would look into if you installed too many clutches or steels or maybe in the wrong order which whould cause it to bind.

From the B&M kit:

6 A&B. Because the B&M TransKit comes with one extra clutch for the direct drum, the surface of the direct piston must be machined down 0.140 inch. The extra clutch increases the torque capacity of the transmission. The machining only takes a few minutes on a lathe, so it should be inexpensive for a machine shop to perform the work.

Install the clutches and steels in the direct drum. Stock TH350 transmissions have four clutches and steels, but the B&M TransKit (and complete B&M transmissions) come with five clutches/steels to increase the TH350's torque capacity. You should have 0.050 inch of clearance between the last clutch and the pressure plate.

 

Not sure what you did, nor the solution, but the same thing happened to me a few months ago. I did not rebuild the intermals but replaced all of the gaskets including the pump seal. It wouldn't go into reverse and would only move forward in higher gears.

My solution was to get a 200-4R (really what I wanted to do in the first place).

 

I don't know if the TCI kit is like the B&M but I'll have to check. During the install I only replaced what I took out I don't think I had any extra clutches. I'll be bringing it to a trans guy this week to tear it apart and fix it. He said something is not aligned properly with the gear sets and when the pump gets torqued down it is binding something. I'm just glad I don't have to pull it apart again. It's pretty tough to pull the pump from the housing. I had to screw long bolts into to pump to get a grip on it and twisted it to get it out. I read a huge paper on how to rebuild this thing and even made my own jig to hold it upright to ease the installation of the pump. With the first trans, I didn't know anything and put it all back together while it was just sitting flat on my bench and that one is still running great in my daily driver. Go figure.

 

Mabey I should just look into getting an overdrive trans.

 

Your not the Lone Ranger. I was all proud of my excellant rebuild once and when I fired up the car it didn't have any reverse. I had to use it for work so I always had to park where I could leave forward for week or so.

I pulled it apart and everything looked right so I ask a guy at a tranny shop. This was on a GM turbo metric POS. He knew exactly what was wrong. It was the reverse lockout ball and spring on the top of valve body. It was blocking all the oil to the reverse side.

 

In regards to the extra clutch-I just tore mine down and rebuilt it ('85 Silverado with 86,000 original miles on truck). New crate motor was already installed and rear end just had new gears installed). Bubba installed the extra clutch to handle the new power but neglected to machine the drum-every damn bushing, pump, steel, drum output shaft-everything was screwed. Everything got put in a bind and ate to pieces. I'll try and get some pics, but long story short was I had to get the guts out of another tranny and put them in my housing. The good thing is it saved me about 1500 bucks on the truck. Now is the time to make sure it's right, amazing what a good intention and not paying attention can destroy. Not saying you did this, but I will damn sure have this in the back of my mind from now on.

ltlevil

 

Well I found what was binding, it was one of the ring seals on the pump not compressing and getting caught into the first drum as I lowered the pump down. It was the last 2 that got caught and it actually damaged the space on the pump shaft between the two. All in all I'm still bringing it to my trans guy and telling him to just get another pump housing and put it back together the right way. It'll be worth it. I guess I just got lucky when I did the one on my van. Thanx guys for the info.

 

Happy you found the problem before major damage was done-think about your tranny locking up like you shoved it in park at 80 mph... Sounds like yougot it goingin the right direction now

ltlevil