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The transmission thermostat is the thermal bypass valve. I'd flip the pill (i.e. disassemble the TBV, flip the thermostat element that's in the housing upside down to allow for continuous flow through system without a thermostat in the way. That should keep the transmission cooler. That said, 200-220 when towing in the middle of summer isn't too bad...If you're climbing significantly higher 220, I'd be concerned.
Thanks @NickTransmissions . What deeper pan would you recommend?
Any good, aluminum pan will usually work (stay away from Chinese pans). I prefer B&M for transmissions; Derale, Mag-Hytec and Mishimoto also make good pans. Also, make sure you're running your transmission cooler lines in series through both the radiator-based trans cooler and the external cooler...If you're only running through the external cooler, you are missing out on a lot of heat exchange that otherwise takes place when fluid runs through the internal radiator trans cooler. So people advise against running it through the radiator-based cooler, fearing internal leaks but if the radiator is either new or in serviceable condition, the chances it leaks are negligible.
Hmmm... looks I don't have one?
That was my understanding as well so I was a little surprised the dealership master mechanic said to look at the trans thermostat. Can I add one?
That is a k2xx thing. And why would you want to add one?
Im no trans guy… lolol… seriously tho… even if it was possible it’s useless. It basically, as i understand it, it lets fluid out and through the cooler only when trans temp gets up to a certain temp. ‘Flipping the pill’ lets it go through immediately…
Nope, you're correct. @tkdgirl stated what the dealership told her about the "transmission thermostat" and i simply replied with my own thoughts and clarification on the terminology. Dont have time to re read the entire thread to figure out what year vehicle, etc to know if it even applies to her vehicle or not...
It's in my sig.
I don't know? I don't know anything about transmissions. Just want my Yukon to tow without the transmission blowing again.
Ok, in short the transmission thermal bypass valve is bad. So you don't want that. You just need to keep it cool. Stay on top of fluid and filter changes. Get a tune for engine and transmission get rid of the programed slip and set it so the torque converter locks up in 5th and 6th gear. Add an external transmission cooler if you don't already have one. When towing run it in manual mode 5th gear.
She has a 2011 which doesnt have a TBV (which is good - one less problem to worry about).
Right, I was just letting her know she didn't need it.
