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1978 F-100 tranny problem

Just had this transmission rebuilt by someone who does an excellent job on GM transmissions, but obviously not so good with a Ford transmission. It is a C-6, behind a 300 cubic inch six. It shifts great on the 1-2 shift, but lags horribly on the 2-3 shift, like it is slipping. All the guy that rebuilt it can do is scratch his head and say "I dunno...something ain't right." Any clues as to why this shift is so screwy? Band adjustment? Modulator valve out of adjustment?

Reply to
snuffy
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Sounds like it needs its break in adjustments. Just like an engine, everything in a tranny needs to be broke back in once its overhauled. See if he can adjust the bands alittle tighter and that might make up for some lag... But I dont know a whole lot about automatics..

Reply to
pkurtz2

"pkurtz2" wrote in news:PhZBf.58316$0G.2979@dukeread10:

the c6 doesn`t use bands, he screwed something up. pull it and fix it. KB

Reply to
Kevin Bottorff

In the C6, the modulator controls the 1-2 shift based on engine load. Modulator is not a problem if 1-2 shift is good. Second band is externally adjustable but, not likely problem since 1-2 shift is OK. 2-3 shift is controlled by governor in tailshaft housing. First thing I would check is whether it is sticking. This can be done by removing the rear mount and tail shaft housing. If the shift is good when it does shift, I would go for the governor. There may also be a problem with the valve body, but, that can be pulled and double checked for correct gaskets and ball placement by pulling the pan. He should have an ATSG manual with it's diagrams handy when he does this. there are a couple of different gaskets for the valve body. The wrong gaskets can do this as well as incorrect torquing of the valve body bolts. They are very sensitive to correct torque and do not torque nearly as tight as a GM trans.

Lugnut.

Reply to
lugnut

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