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Discussion Starter · #1 ·
Hi everyone, new to the forum and would very much appreciate any opinions on this problem...

Fourth gear slips. When I am cruising at 40mph and higher the transmission shifts down intermittently and I gain about 400-500 rpm. Same as I would if I shifted the gear selector to D3.

It seems to be shifting harder as well, when coming from a stop. The engine revs high and second comes on strangely. It just doesn't feel like things are meshing too well in there.

I've talked to a guy at work who recently had his tranny almost entirely rebuilt bit by bit due to something very similar and he says it came down to worn valve bodies.

His explanation seems good, but the shop I am taking it to next week (who had it for half a year last year and didn't find the problem) swears it's electrical. I am hoping to convince them it's not but I don't know transmissions very well.

The truck itself was my late granddad's and it only has 80k, although 85% of those miles were probably spent pulling a fifth wheel.

Sorry for the long post hope you all are having a great weekend!
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