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jamis · 07-17-2005, 09:49 AM

Sorry to have to disagree with some of you on the bolt issue and this is just my opinion base on my experience. I think the problem is more the use of washers then the bolt being too hard. I was in the engine machining and building business many years ago and have built hundreds of engines without ever seeing a bolt failure because the bolt was "too hard".
Just because an engineer put a grade 5 bolt there does not mean it is what is best. A lot of the time, cost of production wins over service life. We have a large fleet of Peterbuilt trucks that keep snapping the gearbox bolts. Someone will get hurt or killed one day. None of the engineers can come up with a solution, we have tried every bolt ever made. The problem is in the gearbox not the bolts. But the pride of the engineers wont let them admit it or the bean counters at the factory wont recall them till some one is killed and family sues them.
Here is a little chart to show you the different bolt grades.

07-17-2005, 09:49 AM	#11
jamis F.A.S.T. president Join Date: Sep 2003 Location: Florida Posts: 1,883	Sorry to have to disagree with some of you on the bolt issue and this is just my opinion base on my experience. I think the problem is more the use of washers then the bolt being too hard. I was in the engine machining and building business many years ago and have built hundreds of engines without ever seeing a bolt failure because the bolt was "too hard". Just because an engineer put a grade 5 bolt there does not mean it is what is best. A lot of the time, cost of production wins over service life. We have a large fleet of Peterbuilt trucks that keep snapping the gearbox bolts. Someone will get hurt or killed one day. None of the engineers can come up with a solution, we have tried every bolt ever made. The problem is in the gearbox not the bolts. But the pride of the engineers wont let them admit it or the bean counters at the factory wont recall them till some one is killed and family sues them. Here is a little chart to show you the different bolt grades. __________________ F.A.S.T. President and Founder Fabricators for the Advancement of Sawsall Technology "A fear of the Sawsall is a sign of retarded sexual and emotional maturity." ~Sigmund Freud, "General Introduction to Psychoanalysis" Last edited by jamis; 10-05-2007 at 07:12 AM.