Earliekyler

Stupid question but I just wrestled new motor mounts into my 6.0 2500hd truck and replaced the factory bolts that attach the mount to the block (4x 10mmx1.5x20mm) with good auto grade 10.9 Flanged bolts (no washer has a head desighn with them).

However the factory bolts bolts have a bolt with a washer, non flanged head. This was not put there to reduce micro pressure on the bolt allowing the washer to slightly move under stress was it? I have a tendency to overthink things and with the equipment I work on for a living these things sometimes make a difference.

Has anyone had issues with flanged mount to block bolts failing? I would think when tight they won’t move but mine were loose when I took it apart,whoever did this job in the past d$@@ed it up good, never used a 10m 1.5 tap so much in my life on one job....(did the classic broken exhaust bolts as well 8mm)

Thanks

LLLosingit

iTrader: (4)

You are over thinking it. If it needs a washer add one if it's a flanged head bolt then a washer is not needed. As long as they are the appropriate grade and they are tight they will hold.

Earliekyler

Cool thanks I was thinking along those lines just couldn’t decide why GM put crimped washer bolts in there instead of flanged I have learned with “modern” engeneering to question everything, I’m use to big rig engines that have oversized everything I get nervous on little car metric fasteners, of course newer semis are just as bad now

i figured with the big power on these forums I’f there was an issue you guys would know, I will be getting a camaro or firebird in the next couple years so I joined now, they were THE cars when I was younger and it’s a life goal