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Sorry for the rudimentary question here... got back from a drive tonight and thought the exhaust sounded raspier than usual. Went to check the exhaust pipe screws - both had completely backed out. I put a new exhaust on maybe eight months ago? All the hangers are in place, and the two screws had been torqued to the 18-20 ft. lbs. mentioned in the SM. I found it curious in the parts books that no lock washers or springs are listed as part of the assembly. Should some hardware like this be used, or is it a place for Loctite? Or is it just simply a matter of retorquing every so often until it just stays put? TIA...

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I always use lockwashers.

Loctite isn't gonna work since it loosens with heat. I agree with Ross on the lock washers, probably external tooth will work best in this application. Lot of thermal cycling going on.

I wonder if a serrated-face flange bolt like these would be a good fit.




Picture taken from BoltDepot.com

My car had lock washers when I took the exhaust apart and so I put lock washers back on.

I have seen regular split lock washers break on exhaust manifolds, but are usually rusted in place by the time they do break.

AI thinks Nord-Lock washers are the best answer. Similar to the bolts BigKev suggested. (I've never used these before, but they look interesting.)

Yup, Nord-Lock is the best option but probably overkill here. They are like $5 per bolt instead of 5 cents.

Now, if everyone's exhausts had been falling off for the past 70 years, I would have a different opinion.