New Duramax Question
Hey All, I'm considering a new GMC 3500 single rear wheel diesel and have never owned a diesel before. How often do you have to change the fuel filter on a Duramax? Every 5000 miles? 10000 miles? M...
Forum Discussion
ATF needs to be changed every 24 months with the dealer supplied TES 389 or every 48 months with TES 295 which is available at Allison shops.
The former fluids engineer for Allison who helped develop the TES295 says that a drain of the transmission pan and refill with Transyd then another drain and refill with Transyd will give you an equivalent of a full change of transmission oil. After that Allison does not recommend any further change. An occasional oil analysis may help to tell you how it is holding up.
He has an open post in the Class A forum and uses the name "hzjcm8". Lot's of good reading. Of course everyone can change their oil and often or as long as they wish.
