On my way down to southern california on sunday in my 94 the 47rh tranny acted funny a couple times just before the grapevine. Cruising along at 70-80mph all the of sudden the torque converter would unlock, then lock back up a couple second later. This freaked me out thinking something bad might happen on the grapevine. Well i slowed down to 65-70mph and it never did it again. It did it probably 5-10 times in a 50 mile section between fresno and the grapevine. Even going up the grapevine at 63-67mph in OD and it stayed locked up no problem and have driven it 400 miles since sunday with no problems. I had the tranny drained yesterday and the guy said it was overfilled, could this have caused this? He said the fluid looked great with just a bit of tiny metal shavings and no clutch material and he said its nothing beyond normal for the tranny. Anyone know what might be wrong?

Thanks, Sean

 

A lot of the weird locking/ unlocking can be attributed to a bad TPS sensor. They can be cleaned inorder to buy quite a bit more time out of them, otherwise it is a pretty expensive part.

https://www.dieseltruckresource.com/...n&onlynewfaq=1