Have heard that the 4.7L V-8's in the Tundra's & Sequoia's are having some exhaust manifold cracking problems.
Wondering of this is also a known problem for the 4th Gen V-8 4Runner.
If so are there any TSB's for the problem.
Cannot seem to find any posting related to this in the forum.
Thanks, Tom

Not sure, I have heard of a few. Mine seems to be OK at 120K. Is there an easy way to check? Does it throw a light? I read one viewer had to get one side replaced. Cost him about $1,200! Ouch!

Had my truck in for the 75k service. My tech said he heard the exhaust leak causing some sounds. He says he's done a few of these repairs on gx470, tundras and sequoias.

i know first hand they do go. i bought my '06 v8 1 year ago. i would notice every time i start it that it sounded like the starter was still engaged. after a while i would hear an exhaust leak outside the vehicle.

i found the crack and sent it to my local dealer. after confirmation that it was cracked they replaced it for free because the cat is attatched to the manifold and you can't buy them seperately. so it was warrantied under the emissions warranty. saved me 1200.00.

as long as the vehicle has under 80000 miles toyota will warranty it.

How would I be able to distinguish between a cracked manifold and valve tap??

My last car had an exhaust leak on an aftermarket header. It had a fluttering sound with the pssshhhh air flowing sound.

I wonder if these cracks are consistently in the same place? Where was yours? That way I know where to start looking.

Well, valve tap can be diagnosed with a stethoscope.

Typically the exhaust leak can be detected with a smoke test.

Bought a used 07 T4R V8 in April 2011 and had the ticking sound and sulfur smell everybody is describing start in August. Thanks to the info I found on T4R.org I went to the dealer and told them that it was a manifold issue and that is should be covered under the emission warranty. The truck had 75,000 miles on it. They checked, confirmed it was the passenger side manifold and replaced it for FREE. :-)

If not covered it's $1500 in MA to fix it. Thanks T4R.ORG!

The dealer didn't want to have any warranty work related to mind. Then again, they couldn't find any cracks, and it was likely the gasket, which they didn't want to mess with under warranty.

Exhaust manifold leak/tick
ticking in the morning

2 threads on it in the last 2 weeks...

Noooo my '08 is at about 163k... So they won't warranty it after 80K? Damn.

this thread is nearly 11 years old. most people replace them with doug thorley headers or the like

I see. What about the disclaimer on Doug Thorley's saying you can't have them for a street vehicle- they are only for racing? lol Can that just be ignored? Or is it an emissions thing? If you know.

Depending on your state, you may or may not be able to fully legally do it. California is a no-go. I'm not sure what Washington's (state) laws are.

At the federal level, the government is concerned that your vehicle maintains the same number of catalytic converters that it was sold with and that it still meets its emissions standards. Technically, it is illegal anywhere in the USA to eliminate any emissions equipment, and you ~can~ be fined if "caught" running catless or with fewer cats than factory. And also technically, no muffler shops and the like are legally allowed to install anything that results in less cats being on the car. In reality, nobody does anything about it. My shop installed my long tube headers while a georgia state patrol car was in for service. Literally breaking the law while servicing law enforcement vehicles in the next bay.

HOWEVER, YOU CAN, IN FACT, RUN DT SHORTY HEADERS AND MEET FEDERAL EMISSIONS REQUIREMENTS.

With the shorty headers, you can have the factory cats welded onto them, or have new cats welded on it and have it fabricated fit up to the factory y-pipe.

If you're worried about legality, I wouldn't use long tubes.