cracked exhaust manifolds on 2009 4 litre

hello,

i recently discovered cracks on both left and right side exhaust manifolds. the cracks are right where the ports meet the flange. right side is cracked on one tube and the left side on 2. no check engine lights have appeared but i plugged my scanner in anyway and there are no codes either. i have heard the cracked manifolds can damaged the engine if left unrepaired ( not sure but have been told) so as a quick fix i scraped and sanded the 3 small cracks and used a high temp jb weld extremeheat paste to patch them up.
i cant find any used manifold at wrecking yards and have called about a price on some aftermarket ones and they are 1300 each.
i dont really have the cash to dole out so am trying to weigh my options . has anyone brazed theirs with success? i was also wondering if there are any other options such as omiting the catalytic converters and using a sensor simulator if that is even an option. i would like to keep the truck as stock as possible .
the truck has 390 000 km however the clutch was done at 350 000 and all oxygen sensors have been replaced as well.

any advice would be greatly appreciated.
thanks

 

Depending where they are cracked they may be able to be welded.

Salvage yards can't legally sell used converters so you will not likely find a used one.

 

Can you upload some photos, please?

 

They sell aftermarket ones on ebay for cheap. https://www.ebay.com/itm/2347997185...lp:2332490&itmmeta=01HYNTYJCM09VEV64T84FT99T2

If you're in a financial bind, you could buy them and have a machine shop inspect the flanges to make sure they're flat. Or, pull your existing headers and take them to an exhaust shop to weld up.

 

thanks for the responses, i will try and load some pictures

 

i have found some used ones from a 2005 4 litre engine, im assuming they will fit just fine? one of the wrecking yards told me that the manifolds change in 2009 and were more prone to cracking is that true?
i will upload pics at some point i just havent had time.

thanks

 

The 05-08 will not flow as well as the 09-11 manifolds.

Also, you risk a much older much more used catalytic converter.

 

Is there a reason they won't flow as well? Would it effect engine performance and cause the engine light to come on. I'm also wo seeing since the cats are good on mine If they could be put in place of the ones on the used manifolds if they were to fail. The manifolds I'm thinking of getting have 180 000 km on them. I looked into aftermarket aswell but alot are getting very poor reviews and don't last long.
Other than the issue of less flow these manifolds should bolt right up to the existing engine correct?
Did the exhaust change between the 2005 and 2009 models even though they are second gen trucks.

Thank you?

 

There was also a TSB on 2005s about exhaust manifolds making annoying ticking noise. I remember getting mine replaced many years ago. So 05 may well be slightly different from 09.

 

Better laminar flow from the design of the 09+. The 05 is a true log design.

 

Oh ok. But it would still be a direct bolt in correct?

 

Yes

 

are there any good aftermarket manifolds that people suggest or even headers that i could have the catalytic section welded back onto?
just trying to weigh all my options. good point about the different design and condition of the cats on the ones i sourced.

 

Ok I'll try and find the info in that thread. Thanks

 

Doug thorly makes some shorty headers you could weld the stock cats on

 

That link was meant for a different thread. Apologies.