2008 4x4 Chevy suburban that pulls a 20' boat
The rear was done at 100,000
How often should it be done ?

 

60 000 miles is the regular service interval. severe service ie towing would be more frequent...not sure what the service manual says


i would do it at minimum, when its black...that could be every 20 000 miles. that is why it is checked at every oil change.