Informative 6T40 Automatic Transmission PDF

[Maddmatts]

The transmission cooling system is pretty simple. Hot fluid goes out one hose to a heat exchanger in the cold side of the radiator and the cooled fluid is returned by another hose.

The manual does have a flow test procedure but requires specialized equipment to carry it out: Chevrolet Sonic Repair Manual: Transmission Fluid Cooler Flushing and Flow Test

 

[Pirate Luke]

The transmission cooling system is pretty simple. Hot fluid goes out one hose to a heat exchanger in the cold side of the radiator and the cooled fluid is returned by another hose.

The manual does have a flow test procedure but requires specialized equipment to carry it out: Chevrolet Sonic Repair Manual: Transmission Fluid Cooler Flushing and Flow Test

Interesting. Thank you for that link. This does seem very likely in my case. Temps rise quite a bit higher than usual and the whine/whirring noise appears. It doesn't seem to do it at start up, only after driving a bit. What controls the flow of fluid from the transmission? The transmission itself?

 

[djbridg]

This is a quote from blue moon sonic on my thread …

As a side note, you don't need a year correct transmission in these cars. I have a 2014 trans in my 2012 with no issues despite the TCM programming and hardware differences between the two. You can even throw the RS auto in there and it'll make the car less lethargic to drive due to the final drive ratio change.

I know this is a really old thread and I am throwing darts at this point I got a 2012 Chevy Sonic with a bad 6t30 I cannot find another 6t30 so I bought a 6t40 and it bolted right up the only problem I had is my axles didn't fit in there and I stopped and pulled the transmission out and found another 1630 in the meanwhile that I bolted in and it didn't work so now I'm back to the 1640 can I put this in use the 6t40 computer and buy new axles