I recently took my 2018 1500 GMC Sierra 79,851miles to Valvoline for a oil change and they suggested I get a transmission flush and differential flush. Within the hour of getting the trans flush, I notice the transmission temperature had surpassed 200° and reached 230°. I took it back to Valvoline and they stated that a fluid flush wouldn't cause the transmission to overheat. They also told me that I should take it to a transmission shop to see what was causing the problem. By the time I made it back home it had reached 261°. The following morning I checked the cold level and it seemed to be within the cold marking on the dipstick. I took it back to Valvoline and after talking to the Manager he offered to re-do the flush and to no avail nothing changed. I was finally able to get it to the dealership and they told me the Thermal Bypass Valve was the problem. I had the dealership replace the Thermal Bypass Valve and that resolved the problem. Now that I have had my truck repaired, I took it back to Valvoline and they insist on the fluid change not causing the issue. Please advice.
- It could I would not use any kind of chemicals in that system I would just drain and refill when it's worn out
Thank you for your time and advice Scotty. Great Channel.
Do not ever go to quick-lube establishments for service. They are just unskilled guys off the street, often ham-fisted halfwits, and they will just destroy your vehicle.
What should've been a simple oil change at Valvoline, ended up with a up sell and overheating transmission after they damaged the Thermal Bypass Valve. They deny having anything to do with the failed Thermal Bypass Valve.