Uses transmission fluid

2003 Chev S-10, 4.3, auto, 4x4. Uses transmission fluid, low vacuum, idles pretty smooth, but just doesn’t run good. Any ideas?

If it’s not leaking on the ground then the only two places it can go is into the engine cooling system or into the t-case adapter between the transfer case and the transmission.

Any chance that this transmission has a vacuum modulator? I think it’s too new for that, but if it DOES have one, I would say that’s definitely the culprit.

It’s a 4l60e transmission, so it’s all computer controlled.

My brother has a Ford C6 that is sucking trany fluid through the modulator…it eventually puddles up on the passenger side floor from one of the heater control actuators. Never seen anything like it.

I asked him what he as going to do about, he replied ?open the door and let it drain out?

Yes, GM products were famous for sucking out transmission fluid through a defective modulator. White smoke in the exhaust was a sure tipoff. Newer transmissions are elctronically controlled, so this one may not have a vacuum modulator.