Chevy & GMC Vans

I have a 2011 Express 1500 AWD with 150k miles. It has been through 3 transmissions in 4-5 years. It has been to 3 different shops, and no one has been able to figure out what the problem is. The first time the transmission went out, I had a new rebuilt one put in. Shortly after, I began seeing smoke out the back of the van. Trans oil dripping on the exhaust. This smoking never happened with any rhyme or reason, very inconsistent and occasional. Brought it back to the shop, they replaced cooler lines, nothing changed. Then they put a different new tranny in. Symptoms went away just long enough for that tranny to drop out of warranty, then it fully failed this past February. Had another new tranny put in (#3), and it’s still smoking. Seems like maybe the fluid is coming from the vent hose?, but difficult to tell. Please help.

I would take it back to the shop that worked on it. Either they botched the install, or it's not the trans.

The current trans is still under warranty, but the shop that originally did the job is 7hrs from where I live. I have been utilizing the nationwide warranty, but the shop closest to me that I’ve brought it to multiple times basically told me that they don’t know what the issue is and to stop bringing it there. So I took it to a different shop that is also under the nationwide warranty, they replaced the pan which they found to be warped. Couple of weeks went by and it was right back to its old ways.

I believe something is causing the trans to overheat. All of these shops are treating the symptoms, not the cause.

Is it overfilled?

Negative. Fluid level is not overfilled.

well they need to find the source of the leak. Why do you think it's overheating?