2006 Sierra pickup with 115k miles. Never changed the transmission fluid. It "clunks" every once in a while when putting in Drive. Should I crack it open now?
Country: United StatesMake: GMCModel: Sierra 1500 Classic SLYear: 2006Engine: Small V8
Hello, I'm Cam. Please include all the details about your issue so I can accurately advise you. I cannot see your vehicle so please be detailed.
My question is should I try to replace the transmission fluid in my truck, and if so, what is the best method. I've heard that over 100k miles, it's better not to crack open the transmission.
OK, some clunk is normal, but it could be a sign of the u-joint failing.
Do you get the clunk when you drive or just going into gear?
Just going into gear.
Ok, check the u-joints. the drive shaft needs to be removed to properly check them.
As for the fluid, it would be a good idea, dropping the pan is the easy way, and changes about 40% of it. a flush in line is the best way and changes over 90% of it.
So you don't necessarily agree with the "over 100k miles" rule?
If it h as never been done then it should be done, even GM says that.