Originally Posted by NSP-Jake
Threads changed in 2004 to a coarse M11x2.0 - believe me, I have a 2004 Deville in the shop right now and it has these M11 bolts. This one still had tight bolts. A 2005 I recently had done, had 5 bolts pulled (also coarse thread). A 2006 again, all tight. It'* hit and miss with thread failure. GM'* warranty division paid for it.
According to Gm service manuals mid 90s blocks through 2004 changed through out the year. For example 98yr bolts are 10x1.5, 2004 bolts on the top are 8x1.25 and the bottom row 10x1.5. 2005 was the year change 11x2.0.
The hg repairs on these cars are good money makers, but I would never own one. Putting myself in the customer shoes spending 5 grand on a hg and thread repair. Comes back months later with bolt/* pulled. What do you tell them now since they just spent over what the car is worth. You just admitted they are hit and miss. 50/50 imo.