exhaust gasket keep blowing out on Gen 2.5

[Cosmos99]

Shortly after I replaced the passenger side exhaust manifold with an OEM manifold I got another leak. Shop said it was the lower gasket on the manifold where it connects to the rest of the exhaust system. They replaced it with a new gasket and all was good. A few hundred miles and it came back. The shop then got an OEM gasket and that too has blown out. I took it to another shop that specializes only in exhaust systems ( been in business for 30 years ) They replaced it 2 times now....There are no alignment issues with the system and it seems to be heat that is blowing them out. Anyone have a suggestion as to what could be causing this? I am on my 4th gasket in 1100 miles.

 

[Salonika]

What’s the exhaust shop suggesting? Only thing I can think of would be making sure all the rubber mounts are correct......exhaust systems are made to “float” and move a little. Make sure nothing is hard mounted to the frame.

 

[Cosmos99]

What’s the exhaust shop suggesting? Only thing I can think of would be making sure all the rubber mounts are correct......exhaust systems are made to “float” and move a little. Make sure nothing is hard mounted to the frame.

The exhaust shop guy seemed annoyed with it. He said nothing seemed wrong. Basically told me this is the last time he will replace the gasket. I am going to get it on a friends lift soon and poke around myself.

 

[Toasty]

Maybe the shop over tightened it, a lot of mechanics don't believe in proper torque especially guys at exhaust or lube shops. Try replacing it yourself, borrow a legit torque wrench. Make sure the surfaces are clean and flat.

 

[RyanY]

Run a metal file across the mating flanges - high spots will show up right away and tell you how flat the surfaces are.

 

[Cosmos99]

Maybe the shop over tightened it, a lot of mechanics don't believe in proper torque especially guys at exhaust or lube shops. Try replacing it yourself, borrow a legit torque wrench. Make sure the surfaces are clean and flat.

It's odd because both shops are VERY legit. One even cleaned the surfaces before installing the 3rd one. Exhaust shop guy says its blowing out due to heat....I run a bluetooth OBDII app and nothing is amiss and the temps are spot on. Last one didn't last 400 miles. If the current one fails I will take it apart myself and see what I can do

 

[evomaki]

This may be a very stupid question, but what is the condition of your motor mounts? Maybe get someone to observe from the side with the hood up as you load the engine with foot on the brake.

 

[Cosmos99]

This may be a very stupid question, but what is the condition of your motor mounts? Maybe get someone to observe from the side with the hood up as you load the engine with foot on the brake.

Good call. I will check that today.

 

[Cosmos99]

UPDATE: over 1000 miles on the last gasket replacement. Seems to be lasting this time.