[Mark R]

This is an excellent video on Torque to Yield bolts, like the kind on the suspension of our cars. When he talks about "bananas" he is referring to a spate of bent frames on small pickup trucks that have been happening in Australia, as an example of metal fatigue.

https://youtu.be/-NKsNtHKpmE

[h018871]

Thanks for that, good on ya mate

[19Nasty1le]

TLDR??

[waterman]

Originally Posted by Mark R

This is an excellent video on Torque to Yield bolts, like the kind on the suspension of our cars. When he talks about "bananas" he is referring to a spate of bent frames on small pickup trucks that have been happening in Australia, as an example of metal fatigue.

https://youtu.be/-NKsNtHKpmE

Good info, thanks for posting.

[Mark R]

Now that I know the TTY bolts in the suspension get stretched when they get torqued down, it makes me wonder why they just don't put in bolts with higher strength that dont get deformed in the first place.

[Mark R]

Originally Posted by 19Nasty1le

TLDR??

I warned you. It's a deep dive.

[arpad_m]

Originally Posted by Mark R

Now that I know the TTY bolts in the suspension get stretched when they get torqued down, it makes me wonder why they just don't put in bolts with higher strength that dont get deformed in the first place.

In the video Cadogan says it's to allow the use of smaller bolts to achieve the same clamping force, which leaves more room in these typically tighter spaces and is likely cheaper as well. The downside, of course, is the required replacement when the bolt is loosened or removed.

[Heartbreaker]

Originally Posted by arpad_m

In the video Cadogan says it's to allow the use of smaller bolts to achieve the same clamping force, which leaves more room in these typically tighter spaces and is likely cheaper as well. The downside, of course, is the required replacement when the bolt is loosened or removed.

There is plenty of space for non TTY bolts. Just did the second alignment alignment adjustment after 11 track days. Re-used the TTY bolts. For a car designed for track use I’m real surprised by GMs use of TTY hardware. TP

[Mark R]

Originally Posted by arpad_m

In the video Cadogan says it's to allow the use of smaller bolts to achieve the same clamping force, which leaves more room in these typically tighter spaces and is likely cheaper as well. The downside, of course, is the required replacement when the bolt is loosened or removed.

I heard that. That makes sense for a bolt in an engine that won't get removed except for a rebuild, but not for suspension alignment bolts. And have you seen the suspension bolts? They are quite large. It's a head scratcher.

[nprario]

Very informative, thanks for posting.

[arpad_m]

Originally Posted by Mark R

I heard that. That makes sense for a bolt in an engine that won't get removed except for a rebuild, but not for suspension alignment bolts. And have you seen the suspension bolts? They are quite large. It's a head scratcher.

Yeah, likely cost savings or a supplier deal on the TTY bolts.

Then again, I have leftover extras for the rear cradle I bought for the BMR lockout kit install just in case, and they do look ginormous, but who knows, GM might have needed to use even thicker ones if these weren't TTY. Al Oppenheiser described in an interview how they got rid of unneeded threads on many bolts to save weight, it could be that, too, as part of an overall "bolt diet".

[Mark R]

A "bolt diet" that is also another profit center. I bought all new bolts for my BMR arms, cradle lockout, etc, and they were around $145 at the dealer, if I recall correctly.

[Rnovrit]

I wonder if ARP makes hardware that will swap? Maybe use a stronger fastener? My thought eventually was to just lock down the adjusters and use BMR adjustable rear suspension arms. This way the factory adjusters are no longer needed. At least this makes sense in my head at the moment. Lol!

[Mark R]

Originally Posted by Rnovrit

I wonder if ARP makes hardware that will swap? Maybe use a stronger fastener? My thought eventually was to just lock down the adjusters and use BMR adjustable rear suspension arms. This way the factory adjusters are no longer needed. At least this makes sense in my head at the moment. Lol!

It makes sense to me. If I had known about the TTY bolts when I got my BMR arms, I would have opted for the adjustable ones. I'm glad I have their toe rods, because the rear toe was always out with the stock arms and bolts.