th350 broke in reverse

[TIC]

back in Oct. i rebuilt a 74 mod. th350 tranny, useing hotrods excellent photo in structions, the build went well, no leaks, shifted perfect. the only thing i noticed was when i was in reverse and tried to move backwards it felt like it didn't want to move, till you gave it enough gas, like something was binding, i asked for help but never got a reply. well last sun. i was trying to backup a trailer and it felt like i was up against a tree, it didnt want to move so more gas, then bam somthing broke, now no reverse. goes forward and shifts fine, but no engine braking when i pull down in 1st. i know its to late. but could anybody tell me what the problem could have been? im gonna rebuild the 700r that i took out and put it back. so im not gonna tear down the th350. but for my and others info. id like to know what went rong.

 

[crazy4offroad]

Low/reverse roller clutch likely grenaded. Check if L1 is gone too, it is likely taking off in 2nd gear.
EDIT: also sorry for the no reply on your question before. I don't get on as much as I used to and there seems to be so many people asking questions here these days it's impossible for me to check them all, so many get bumped down the list.

 

[TIC]

i do have 1st. whats eating at me is why it was binding in the 1st place, i know i did something wrong, is it possible a forward clutch was engageing at time reverse clutch was locking up? i doubt if disassembling would show why. you could tell there was some conflict going on when in reverse, no sound just felt like it was trying to overcome some resistance, i had to keep giving more and more gas to get it to start moveing.

 

[crazy4offroad]

I toasted the forward clutches by having 1 spring in wrong in the valve body, could have been something as simple as that. Tomorrow when I'm at my pc I'll post an exploded view of the valve body, might be the easiest place to start checking.

Sent from my SCH-S968C using Tapatalk

 

[crazy4offroad]

Here's the view of the valve body, note some of the springs have a small end and large end, that's what killed my forward clutches, just putting 1 spring in backwards. Might have to download it to view it full size. Hope this helps...

 

[TIC]

thanks for the info.

 

[HotRodPC]

Or the Low/Reverse Clutches got hot enough to weld themselves together.

Yes, First is certainly Possible from Drive. Low/Reverse are only used for Manually selected Low and Reverse.