Cracked Titan manifolds for your viewing pleasure

[sasilverbullet]

Both my 04 Titan's manifolds cracked. From what I've read, almost everyone gets cracked manifolds. 78K miles on it. Found a set of used one's from the Titan forum for only $300 for the pair. New is $850 ea from the stealership! Took a lot of work to put them in, blow torch on the bolts, etc.

Runs better now that the computer doesn't have more air sucking in throwing things off.

Here's pics of the cracks.

What do you guys think the cause of the cracks are?

 

[Rand]

manufacturing or engineering defect.

 

[Bill in Utah]

Can't beat plastics these days....
Seems all manufactures are having "features" issues.

Bill

 

[Clevy]

850 for manifolds. Wow. I'd have gone with headers and said forget the whole manifold idea.
Are we saying that these exhaust manifolds are made from plastic?

 

[electrolover]

Many heat cycles and poor metal choice. Your new ones will crack too.
I can fix your old ones if you want.

 

[bmwtechguy]

Nissan quality (engineering and materials) all over the map? Kinda like most manufacturers these days.

 

[Bill in Utah]

Originally Posted By: Bill in Utah
Can't beat plastics these days....
Seems all manufactures are having "features" issues.

Bill


Thought these were intake. Guess they are exhaust.

 

[Sayjac]

Good work on the DIY to repair the issue and save some $$$$. At least they didn't terminate your engine like the failed precats on 03 Altima.

Based on my experience what caused it was previously mentioned, lousy Nissan engineering and materials.

 

[Brons2]

Known issue on the Titan. I used to have an 04 a few years back.

The NISMO headers are less expensive than the stock replacements. The used ones you got will crack eventually. I would weld the cracked ones and when the used ones you just got crack themselves, put the repaired originals back on.

 

[Chris142]

They Look tubular. If so they need to add flex tube to them to allow for expansion and contraction

 

[ls1mike]

Did you do a lot of heavy towing or is it just a poor design?

 

[ls1mike]

Reread your post. Looks like a weak spot in a bend, then the heat and cooling cycles cause it to crack.

 

[The motor guy]

Could have just paid someone to weld that up for 50 bucks. May or may not have worked but it's worth a shot.

 

[Black_Thunder]

is it just me or do these not look like cast manifolds?

 

[SuperDave456]

Looks like a pipe that was bent and welded to the mounts instead of a cast manifold. If it is cast, they are very clean castings.

If, When it happens again do some research on welding them up. Or getting aftermarket headers.

Like the other guys said. There are many options.

 

[NHGUY]

Nissan probably went cheap because they sell hardly any of these trucks.Hard to spread costs out when you dont move any product.Now if they were selling 200K of these.....maybe just maybe they would beef them up.

 

[Pop_Rivit]

Originally Posted By: sasilverbullet
Found a set of used one's from the Titan forum for only $300 for the pair.


Did it really make sense to put a used set on, given that it's a known issue that almost all those manifolds have? Aren't you just setting yourself up to do it again in a couple years?

 

[A_Harman]

Constrained thermal fatigue is one of the most powerful forces in the universe. A thinwall structure that has no strain relief can only be heated to 1400F and cooled again a finite number of times before it cracks. Buying a set of used ones is a [censored] shoot, they may be ready to crack tomorrow or maybe they'll last 5 years. Long tube headers may actually last longer, and give you better performance in the bargain.

 

[electrolover]

Id weld or braze em ( depending on the metal) for around $50

They dont look to be cast iron by the pic, but its hard to tell with out testing them.

 

[INDYMAC]

I had this problem with Pathfinders. Luckily, they all cracked before the powertrain warranty ran out. This is also a problem with Toyota Tundra's. Unfortunately, they seem to crack after warranty. Shorty headers with good quality gaskets are the way to go for replacement, and cost much less than OEM.