1990 chevrolet transmission vacuum modulator diagram

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The thing makes an unbelievable mess when parked in any one place for more than about 4 minutes. Pulling the valve body is giving me a chance to get most of the leaking seals in the trans.

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The governor screen was completely clean.Īnyone have any suggestions for getting the retaining pins for the shift valves out (below)? They appear to be pressed in and I'm not real sure how to get enough leverage on them to get them out. Knowing that this truck hasn't had a lot of love, I'm surprised it looks so good inside. There's no scoring or any real signs of wear. If it's not that, then I'm completely at a loss. I'm assuming the seal failed, opening the circuit at all throttle positions. The screen is in the middle and the solenoid is on the right.

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