Blown HG - What could cause this?

[humroot]

Hi All,

I have a blown HG on cylinder 5. Picture attached. Any thoughts on what could cause this? I replaced the HG's in 2018 with Elring and used ARP studs, less than 20k miles on them.

A week before this happened, I got an overheat in my transmission. My current thought is a bad cat that caused too much back pressure and blew out the HG. The bad cat would heat up the transmission pan and possibly cause the overheat.

The only code was for misfire on cylinder 5. No overheat since last HG job. Appreciate any thoughts.

Thanks,
Jamie
2001 Disco 2 SE7
195k miles

 

[Flyfish]

I would guess the misfire was from the hg failing. Hard to say the tranny issue, cat and hg failure are all related. Maybe the heads weren’t perfecly level when you did the last hg job? Or an issue with the gasket itself. Check that head and block surface.

 

[salvvia]

Land Rover factory Engineers

 

[discostew]

Land Rover factory Engineers

It's Buick's engine.

 

[toadermcgee]

Its a Land Rover, that is what caused it.