Exhaust Manifold Crack

[Brandon.miller6]

I have a 1999 4.0 with a cracked manifold. (Confirmed from soapy water test and loud knock when I start it). What is the general consensus of brand to get? Based on research it seems that banks has fixed their old design to not crack as easily however it’s $500. Where as a Dorman is $170. I’m also going to install a piece of flex tubing to hopefully reduce the chance this happens again.

Is there anything else I should look at replacing while I’m in that general area, like motor mounts? Thanks.

Banks : https://bankspower.com/products/exhaust-header-51327-1991-1999-jeep-wrangler-4-0l-1991-1998-cherokee

Dorman : https://www.google.com/aclk?sa=L&ai...xWbJ0QIHcguNQQQn5wLegQIERAB&nis=8&ch=1&adurl=

 

[KennethS]

FYI, many years ago I replaced my cracked manifold with a Banks Torque Tube header. After a lot of years, the Banks header cracked, too. I was able to get a warranty replacement as mine was purchased when they had a lifetime warranty.

My diagnosis of the manifold cracking is the entire exhaust system sways on the hangers and applies force to the manifold, which is the front anchor point. If you can stop the exhaust system from swaying that would remove the force and prevent the cracking. I put a universal exhaust hanger up front near where the pipe turns and goes under the oil pan to prevent the new Banks header from cracking (it does not have a lifetime warranty).

 

[KennethS]

If you want a generic replacement manifold at a super discount price, I can send you the one I put on temporarily until I got the Banks replacement.

 

[macleanflood]

I'd do a Banks plus Cerrokote or a cheapie eBay or Amazon if you're on a budget. I'd also get your intake cerrecot

A flex joint added to the front of the oil pan section on the down pipe might help with cracking.

-Mac

 

[Brandon.miller6]

I'd do a Banks plus Cerrokote or a cheapie eBay or Amazon if you're on a budget. I'd also get your intake cerrecot

A flex joint added to the front of the oil pan section on the down pipe might help with cracking.

-Mac

What’s the benefit of adding cerakote?

 

[macleanflood]

What’s the benefit of adding cerakote?

Reduced intake air temperatures. Cold air more power. Might lead to better mpgs.

-Mac

 

[Brandon.miller6]

FYI, many years ago I replaced my cracked manifold with a Banks Torque Tube header. After a lot of years, the Banks header cracked, too. I was able to get a warranty replacement as mine was purchased when they had a lifetime warranty.

My diagnosis of the manifold cracking is the entire exhaust system sways on the hangers and applies force to the manifold, which is the front anchor point. If you can stop the exhaust system from swaying that would remove the force and prevent the cracking. I put a universal exhaust hanger up front near where the pipe turns and goes under the oil pan to prevent the new Banks header from cracking (it does not have a lifetime warranty).

Do you have a picture you could share of what yours looks like?

 

[macleanflood]

-Mac

 

[GoldenGorilla]

I have a 1999 4.0 with a cracked manifold. (Confirmed from soapy water test and loud knock when I start it). What is the general consensus of brand to get? Based on research it seems that banks has fixed their old design to not crack as easily however it’s $500.

Is there anything else I should look at replacing while I’m in that general area, like motor mounts? Thanks.

The reason I chose aFe was the price differential at the time wasn't that large and the header was made from 14ga 409 stainless while Banks and others were 16ga. Better weld strength, presumably better crack resistance. Prices are less close now. When they're having a good sale (now) it's worth looking.

The late TJs with the 2 mini cats have their own issues and aren't as prone to cracks. But I think the idea of an exhaust hanger on the driver side is really smart.

 

[KennethS]

Do you have a picture you could share of what yours looks like?

Yes, if you clarify what you want a picture of.

 

[Brandon.miller6]

Yes, if you clarify what you want a picture of.

universal exhaust hanger up front near where the pipe turns and goes under the oil pan

 

[KennethS]

It’s just one of these these that I bolted to the frame.

https://www.autozone.com/p/surebilt...MIkNqAz46plQMVxzdECB0eNByjEAQYAiABEgJD6PD_BwE

 

[PurpleTJAZ]

I went through three different performance exhaust manifolds in the first two years of owning my TJ. They all cracked. Ended up putting a Dorman manifold on and it’s been flawless for ten years.

 

[GoldenGorilla]

Especially with the early TJs, there's little performance gain in an aftermarket header.