Just recently bought a 2015 GMC Sierra 1500 SLE 4x4. I am the third owner. Shortly after buying the truck the transmission grenade’d itself. I’m at 97k miles so still under the 100k mike power train warranty, however I was 21 days outside of the 5 year part of the warranty. I reached out to GM after returning from deployment to try and get some help and hope that they would honor all or maybe partial warranty. Needless to say no help from GM! Shopped around for shops to rebuild and ended just buying a remand one for 2.7k. So here are my questions:
1. Flush the current cooler or buy an upgraded one?
2. If I should buy an upgraded one then how big?
Also should I bypass the current one in the radiator to have a separate cooling system?
3. I’ve heard of people deleting the transmission oil thermometer to achieve a cooler temp. So say do this because heat is the enemy, others say the trans is built to operate at a certain temp.
3.What temperature is the best operating temperature?
4. Should I have the new transmission re flashed or swap the one from my grenade’d one into the remand one?
5. What’s the best way to flush the current cooler if I don’t change it? I’m afraid if I just try to flush it then it won’t get it clean enough and I’ll mess up the new transmission!
That’s all I can think of right now! Thank you in advance for your time and expertise!
