FSM Bolt Class (ie 5T). Other than what is in the FSM, what yield strength? (1 Viewer)

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The FSM has bolt classes and their associated torques. Has anyone ever found a chart stating a grade 8.8 or 10.9 is above or below a certain 11T etc class bolt?

Where in strength do the Toyota T class bolts sit among JIS/DIN standards?
 
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Easy to find out the difference.

Buy a few Toyota bolts of interest in 8mm size and a few Grade 8 or higher bolts same size.
Torque off the hex head until it shears & compare the results.

Almost every Toyota bolt is still available for the 60/62 except a few transfer case bolts. Just use Toyota bolts when replacing bolts. They're superior anyway with their captive washers and better plating.
 
I've never seen a chart (haven't really looked) but a SAE grade 8 is about a metric 10.9 for tensile strength, but there are differences for fine thread vs coarse... So I think that makes your basic Toyota 8.8 about a grade SAE 5-ish ?

Good question, Randy - I never really thought of this as I always just try to get the OE bolt or bulk replacements of the same Toyota spec. and always JIS as I HATE having (or finding) odd-sized fastener heads (DIN) on a Japanese vehicle.
 
I’ve been meaning to run a few Toyota bolts of various strengths through the testing lab when I test our hardware, but have not yet gotten to that. I’ve also wondered whether the “T” classification corresponds to levels of strength. The only other insight on this would be to match up the torque requirements of the “T” classifications with the same requirements of Metric Class strength. That would give us some idea where each falls. Maybe @beno knows. Grade 8 does indeed equate to Class 10.9 roughly.

All of our carbon steel hardware is Class 10.9 if you need some quality bolts.
 
I am aware of the differences in DIN and JIS, specifically the inappropriate 13mm head on DIN bolts. This question is more out of curiosity than necessity as spourcing hardware has never been a problem with the internet and OEM dealer hardware.
 

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