Tranny temps: how hot is too hot?
I recently got a 5th wheel camper that I will be towing with my 2011 Silverado 1500 LTZ. It has the HD trailering and HD cooling packages (RPO codes K5L and Z82). What would you consider to be high tr...
Forum Discussion
marcsbigfoot20b27 wrote:
Yep, its not just about the fluid.......its also how much heat the seals can handle. One seal failure can mean totally disabled trans.
I worked at a transmission shop for 4 years (23 years ago) Seen lots of burned up units, some with wasted seals and clutch packs where the glue that holds the fiber to the steel was gone.
Anything over 225 for more than 5 minutes and I would pull over or add a bigger cooler. It doesn't matter if you have full synthetic that can handle 350 degrees if the seals melt.
My truck stock would get up to 210 going up the rim in AZ. Added a way bigger cooler and now it only gets to 160 max ever.
I agree if you are driving a 20+ year old truck. The newer units are designed to be able to run hotter (I agree cooler is better) than those 20+ years ago. I know that if I put Dextron VI in my 1973 Turbo 400 transmission that the fluid will handle higher temps but the transmission itself, not so much. Seals and clutches as you say are not built to take the heat that the newer transmissions are.
GM factory is saying the 2007 and up 6 speed (not talking about Allison) can handle more heat.
