I have the infamous GM driveline clunk, I know you can fix the problem by greasing the slip yoke but I don't know what type of grease to use, I have checked my u-joints and they are good. I've heard that you need to use a type that is compatible with the transfer case fluid when it's a 4x4, which mine is. Is there anyway you could tell me what type to use?
My car has 90000 miles.
My car has an automatic transmission.
You can try using transfer case fluid as a lubricant. The transfer case fluid is just automatic transmission fluid. Using the lastest version of Dexron transmission fluid should work out fine. The service bulletin for drive line clunk instructs mechanics to lubricate the slip yoke in order to stop the noise, but if the noise persists, the entire driveshaft must be replaced with a new unit, in which case you may want to contact a certified technician, such as one from YourMechanic.
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