700r4 trans problem

WEEKEND WARRIOR · December 5, 2003

Hi, my friend has a 1990 2500 gmc truck with the 700r4. The problem is it will puke atf fluid out the dip stick when towing. GM had a recall and sent out locking dip sticks to fix the problem but what is the cause. The trailer was light and temp was cold. Thanks

WEEKEND WARRIOR · December 10, 2003

Please help! I am at a loss.

Shaners · December 11, 2003

I would say the tranny is about junk!!! When my father-in-law lost his in his G20 van, it was pushing fluid out the dipstick. My guess it was boiling the fluid.

Is his fluid dark and have a bad odor? If so, then the tranny is ready for a rebuild...

MoJo · December 11, 2003

Pucking fluid is usually overheated, over filled or underfilled. BOTH over fill and underfill can cause 'aeration' of the fluid. Tiny air bubbles in the fluid that cause it to foam. Air in the fluid causes it to heat up. Heat causes expansion of the bubbles, more bubbles, more heat, etc. eventually, it's like shaking a bottle of champagne and then popping the cork. "Old Faithful"!