Originally Posted By: AZjeff
Maybe it has to do with climate? A co-worker has an 06 Sierra 2500 with 140K, I asked him about his and he's never had to replace any either. Do you just replace them all as preventative maintenance or wait til they break?
It's not climate, It has a lot to do with how the truck is used, If it tows at max GCWR alot...It will pop heads off manifold bolts. I guess they can only handle so many extreme heat cycles??
It generally starts with the driver side rear bolt, Losing that one doesn't always create a exhaust leak right away, Its when the next one pops, The driver realizes there is an issue.
This is not isolated to the 6.0L, It effects 5.3L & 4.8L engines as well, They use the same manifolds, Not to long ago, I had a '06 K1500 5.3L come in for a transmission rebuild, It only had 2 bolts in each manifold, So it had 8 broke bolts, He declined the repair & I declined to find out why it runs like [censored]....Try explaining why you cant trouble shoot drivability problems with major exhaust leaks....
I would replace them with ARP bolts as preventive maintenance, Rarely does a customer heed the advice.