Do the new LTx still break exhaust manifold bolts?

[redhat]

On my new L84 in my 2024 Tahoe. Curious if the new LTx break exhaust manifold bolts like previous LSx.

With it being so young, now might be the best time to replace each manifold bolt, one by one, with some new ARP.

Thoughts? Thanks.

 

[clinebarger]

They still do, Replace with ARP.

 

[f355spider]

What causes the bolts to break? Warping manifold flanges?

 

[redhat]

What causes the bolts to break? Warping manifold flanges?

This has been from ‘97 LS1 to present. I’m thinking junk GM bolts. Plus me being a salt belt resident doesn’t help. I haven’t seen a manifold warp when all bolts are good. I don’t think the manifolds warp with sufficient tension.

 

[f355spider]

This has been from ‘97 LS1 to present. I’m thinking junk GM bolts. Plus me being a salt belt resident doesn’t help. I haven’t seen a manifold warp when all bolts are good. I don’t think the manifolds warp with sufficient tension.

Interesting. It is a known issue on Ferrari 430 Scuderias. Both of my exhaust manifolds broke bolts (on separate occasions), and when removed, the manifold flanges were found to be warped. The shop said they had done dozens of them and none ever returned with a recurrence. They would have them ground flat, and replaced all the studs and gaskets upon reinstallation.

 

[clinebarger]

This has been from ‘97 LS1 to present. I’m thinking junk GM bolts. Plus me being a salt belt resident doesn’t help. I haven’t seen a manifold warp when all bolts are good. I don’t think the manifolds warp with sufficient tension.

Cast Iron Exhaust Manifolds move around a lot, The constant expanding & contracting along with the weight of the Y-pipe & Catalyst's works the bolts, Especially the end ones.

 

[GON]

Cast Iron Exhaust Manifolds move around a lot, The constant expanding & contracting along with the weight of the Y-pipe & Catalyst's works the bolts, Especially the end ones.

Should the bolts be replaced as part of preventative maintenance, long before rust and corrosion impact their removal?

 

[Nuclear_42]

On my new L84 in my 2024 Tahoe. Curious if the new LTx break exhaust manifold bolts like previous LSx.

With it being so young, now might be the best time to replace each manifold bolt, one by one, with some new ARP.

Thoughts? Thanks.

Why would anyone mess with a brand new engine under warranty 5 year/ 60k. If it ain't broke don't fix it.

 

[clinebarger]

Why would anyone mess with a brand new engine under warranty 5 year/ 60k. If it ain't broke don't fix it.

Doesn't normally occur under warranty & trying to replace the bolts at 60K can result in breaking a couple.

 

[clinebarger]

Should the bolts be replaced as part of preventative maintenance, long before rust and corrosion impact their removal?

Yes, But selling new bolts on a new/er vehicles is difficult....To the point I hardly ever bring it up with customers.

 

[Nuclear_42]

Doesn't normally occur under warranty & trying to replace the bolts at 60K can result in breaking a couple.

First I’ve heard of mass issues with GM ecotec engines. 90% of engines after 60k regardless of brand will probably break a bolt or two anyways.

 

[4WD]

First I’ve heard of mass issues with GM ecotec engines. 90% of engines after 60k regardless of brand will probably break a bolt or two anyways.

Thinking it happens more on LT’s that tow well into their rating …

 

[redhat]

First I’ve heard of mass issues with GM ecotec engines. 90% of engines after 60k regardless of brand will probably break a bolt or two anyways.

This has been a staple of GM small block v8s from 1997 to present. It’s just a “it happens” kinda thing in the OE bolts.

 

[Gus_Mahn]

Is it consistently just one or two of the bolts that break? I know on modular Fords it was always the rearmost of the tiny studs that failed. Maybe it could be bullet proofed by changing only 2-4 studs.

 

[Strumpan_]

More or less every engine has this problem. At least here in Sweden, I just buy studs before even trying to mess with anything to do with exhaust bolts.