Burnt up transmission

[entodad]

I tore down a 1990 700r4 yesterday that had gone up in smoke for me a couple of years back. I knew something would be toast inside and sure enough it was..
If I wasn't on dialup I would post a pic.

the reaction shell and bits around it had burn up so badly that the gear to the rear of the shell had all of the teeth ground off it.


Questions

1. the output shaft is not buggered up, but is nice and black in that area.
Should I reuse it, or could the heat have torn it up?

2. I have an older 700r4 (1983?), will the gears, shell etc. arount the output shaft be the same as the later model...I ask this since I am a little lazy and haven't looked it up yet.


Also, I experienced my first counterfit bolts yesterday.
Where I thought they were pulling threads, they were actually stretching the bolt and breaking at a torque less than required for holding the valve body down in a TH-350.  Pulled the bolts from another tranny and they torqued just fine.

[Crosley.In.AZ]

what torque are you using on the v-body bolts?

should be 10 - 12 ft lbs on t-350 unit.


I posted a photo of parts that you may be talking about?  A common lack of lube caused the failure. You must check bushing wear / replacement  and the output shaft for debris that will block oil flow. .... OR if the vehicle was tow'd with the drive shaft in , that will tear up the tranny real fast.

the gear trains/parts are swappable in the back end.

Polish the shaft with 240 -400 grit paper wet or dry.  See what it looks like... no galled metal is good.

[entodad]

what torque are you using on the v-body bolts?

should be 10 - 12 ft lbs on t-350 unit.


I posted a photo of parts that you may be talking about?  A common lube caused failure. You must check bushing wear / replacement  and the output shaft for debris that will block oil flow. .... OR if the vehicle was tow'd with the drive shaft in , that will tear up the tranny real fast.

the gear trains/parts are swappable in the back end.

Polish the shaft with 240 -400 grit paper wet or dry.  See what it looks like... no galled metal is good.

Aaaargh, I wrote a reply and lost it on spell check


Again...
The v-body bolts were being torqued to 12 ft lbs. and pulled in two before that was reached...the bolts had a plain head while the replacement bolts had a M embossed on the head....I suspect that the plain bolts were placed into the tranny on a previous rebuild and were only a grade 0-1.

The sun gear on the right looks very similar to the gear I ground smooth..except mine is blacker...
The tranny was a "professionally rebuilt" tranny that i put into my truck as a preventative measure since the truck had about 240K miles on the original transmission.  this one lasted only 18K.  It started to slip/feel funny when I was about 250 miles from home and went out completely just as I got into my home town..
This transmission failure along with another that occurred only 2 months apart, are what caused me to begin learning how to rebuild transmission.  I have made a lot of mistakes, and will continue to do so...but I do try to minimize the mistakes by asking lots of questions...
Thanks Crosley

Doug