Post deleted by sweet97wrangler

i have never once had a problem with my borla header, you could try the flex pipe, might work, or new motor mounts

Yeah motor and tranny mounts are where I"d start. They work for everyone else that owns one of those...how could yours be different?
Big JIm <img src="/forums/images/graemlins/pfft.gif" alt="" />

Are you running the stock rubber engine and tranny mounts, or aftermarket urethane?

Do you think that the driveline really moves that much? My friend with a 2004 wrangler has never has this problem. It looks like Jeep redesigned the exhaust manifold on his.

sweet... From time to time we hear of a manifold cracking. Like any other part of a vehicle it MAY crack. However it does not appear to be a weak link in vehicles such as yours. One thing to remember...we don't hear about the millions that DO NOT crack!
If I was on my third cracked manifold I'd be looking at what was different on my vehicle that was not on other guys vehicles.
Several things might lead to helping the manifold to crack.
HAving the pipes tied down tightly so thay cannot MOVE with the rest of the drive train might help the manifold to crack.
OR having the engine/tranny on broken or loose mounts may also help.
I would imagine having a restricted exhaust system might help build up heat and also might cause such failures.
The common crack that we see here is at a weld on the manifold. MAny of the guys here have welded the crack and put the manifold back in service...with no ill effects.
Big JIm <img src="/forums/images/graemlins/pfft.gif" alt="" />

thank you Jim for the advice. I'll go for new motor mounts and weld up the header. Hope it works!

i have the aftermarket motor/tranny mounts

yea many people weld the cracks because its a lot cheaper and it works