i have a 1994 gmc 4x4 and im having tranny problems what do i need to do to fix it it will shift perfectly when i manuly do it but in drive it stays in one gear or when i go from fist second then drive it free spins and at a certen RPM it will catch a low gear can anyone tell me whats cousing it to do this please thank u

700r4 has a clutch band that controls 3rd n 4th gear the transmission needs rebuilt. My 1990 did the same thing

First try pulling the pan and replacing the accumulator valve. In some gm trannys they are plastic and they become brittle. if not, john is right, pulpit yourself to save some money and take it to a good trannys shop and have it rebuilt.

Don't those have limp in mode so when a valve like that goes it would just stay in second. I personally haven't seen the instance you are talking about on those but at the same time I have only seen about 3 cases of 700r4 failures 1 was my band was completely shot and the other 2 were both internal electrical rendering the vehicle capable of going forward in second regardless of the fwd gear selected. When mine went out first and second worked fine but after it attempted to shift into third it was like neutral till I hit about 3700 rpms and it began to act.like it was back in first with lots of slipping. Take it to a tech there is a slim chance it could be ur 4X4 hoping into N.

What you're talking about is after transmissions went electronic such as the 4L60E, 700R4 has electronic selonoids but very limited and based on speed sensors and throttle pressure sensor. I had a 400 do this exact same thing, I chafed the valve and it was perfect. All I'm saying is check the easier stuff first, then maybe take it to a mechanic. That reminds me, check the cable that goes from the throttle body to the tranny too, sometimes the plastic retainers break and the cable falls off, its for the throttle pressure.

ok thanks i took it to my buddys shop he is going to scan it for me