Looking for advice on this overheating issue.
Picked up a "fleet vehicle" with 216k miles (2019 suburban) and it looks like it has the L83 w/ 6L80 transmission.
I was parked with AC on the car got up to 250F, I thought that was a bit hot and looked at the fluid(which was dark).
so change fluid ~12quart + filter (and installed a drain plug so I can do another fluid swap).
I also added the ppe thermal bypass valve as I read it helps with temp.
Now it looks like the bypass was working as it should as it took some time to heat up the fluid. I tried to load test the system by putting the car in D and sit idle with AC on blast. about ~20 minutes the transmission fluid got to 250 then raised quickly to 280. To which I shutdown the car.
It seems the transmission cooler is tied to the AC condenser? so at Idle w/ max AC it was heating up the trans fluid, turning off the AC and the trans temp would slowly go back down.
Whats the deal with this? is this normal?
What do you guys do for this? it wasnt crazy hot either it was only about 90F outside. (hottest here can get p to 110F and coldest ~40F)
Im thinking of adding a Tru Cool 40k but should that be installed
Trans > OEM trans cooler w/ AC > Tru Cool 40k > trans
or
Trans > Tru Cool 40k > trans
Should I keep the PPE thermal bypass or is the "Superior solution" the better option(im seeing that ideal temp should be ~170-200 so perhaps full bypass isnt the best solution for transmission longevity)?
It almost seems it better to just go with old design and route the fluid to radiator cooler first then the stock cooler stacked with AC condenser then back to transmission? at least radiator would keep temp at set at 210?
Usage wise, we maybe tow a car trailer once a year, main concern is really the wife sitting in a parking lot at idle with AC waiting for the kids to get out.
Picked up a "fleet vehicle" with 216k miles (2019 suburban) and it looks like it has the L83 w/ 6L80 transmission.
I was parked with AC on the car got up to 250F, I thought that was a bit hot and looked at the fluid(which was dark).
so change fluid ~12quart + filter (and installed a drain plug so I can do another fluid swap).
I also added the ppe thermal bypass valve as I read it helps with temp.
Now it looks like the bypass was working as it should as it took some time to heat up the fluid. I tried to load test the system by putting the car in D and sit idle with AC on blast. about ~20 minutes the transmission fluid got to 250 then raised quickly to 280. To which I shutdown the car.
It seems the transmission cooler is tied to the AC condenser? so at Idle w/ max AC it was heating up the trans fluid, turning off the AC and the trans temp would slowly go back down.
Whats the deal with this? is this normal?
What do you guys do for this? it wasnt crazy hot either it was only about 90F outside. (hottest here can get p to 110F and coldest ~40F)
Im thinking of adding a Tru Cool 40k but should that be installed
Trans > OEM trans cooler w/ AC > Tru Cool 40k > trans
or
Trans > Tru Cool 40k > trans
Should I keep the PPE thermal bypass or is the "Superior solution" the better option(im seeing that ideal temp should be ~170-200 so perhaps full bypass isnt the best solution for transmission longevity)?
It almost seems it better to just go with old design and route the fluid to radiator cooler first then the stock cooler stacked with AC condenser then back to transmission? at least radiator would keep temp at set at 210?
Usage wise, we maybe tow a car trailer once a year, main concern is really the wife sitting in a parking lot at idle with AC waiting for the kids to get out.
