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6.2L (L9H) Owners - Get all your questions answered here

RyanbabZ71
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rutwad Enthusiast

rutwad

Posted
Posted

I have an exhaust leak on the driver's side. I thought it may be leaking at manifold, but dealer said the problem is usually the first joint. I checked to make sure the 3 bolt flange was tight. It may not be as bad now but still leaks. Exhaust wrap?? Would a small leak cause less low-end torque?

 

 

Hopefully I have fixed a couple things on my truck to make it perform slightly better. First was a double win! I was taking off my OEM intake to install my Airaid Jr. and I found it had muddy water in it. So with the new intake and absence of water, I should be better off.

 

I swapped my 3.42 gears for 3.73 which is a plus. But I swapped my stock tires for slightly larger BF Goodrich KM2's which are pretty heavy. I don't know if the gearing is enough to offset the tire difference or not.

 

Lastly I uninstalled my Hypertech and am going with the BBP tune!!! Can't wait after reading all the good things about it.

 

 

Johnny

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DanMan_S
DanMan_S

This is a video showing how the 6.2L sounds with headers and a corsa catback. The crew cab is my 6.2L, the 2005 extended cab is a 5.3L with a magnaflow muffler welded in.    

gonzoid
gonzoid

finished product  

2010LTZ4x4
2010LTZ4x4

Where did you get the 6.2L badge in you avatar?  Heres the info for the 6.2L badge Top Flight Reproductions is proud to announce the addition of the 6.2L emblem to our emblem product line. This embl

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STINSAN3 Senior Enthusiast

STINSAN3

Posted
Posted (edited)

If I was gonna get a 6.2L, how many miles should I not go over if to buy one?

When I bought my '07 5.3L it had 102 when I bought it, never did use any oil at all.

Edited by STINSAN3
NemesisC5 Enthusiast

NemesisC5

Posted
Posted

I remember the spacers on the old throttle-body injected engines didn't do crap. Actually, they made them lose power. Don't know why people still bought them ...

 

I'd imagine the same is true for these new ones, although there's no fuel going through the spacer like the old ones, so maybe that changes things ...

 

I'm sure somebody on here has tried one and can post better info than I.

I've read posts on other forums referencing when installing TB spacers on certain Ecotec intakes they will not work correctly unless you grind down a hump or rise just inside the TB flange. I cannot speak to accuracy just passing along.

  • 3 weeks later...
Buddy67Lincoln Enthusiast

Buddy67Lincoln

Posted
Posted

I bought a 2010 Denali Yukon with 6.2 and this morning I heard a tapping or knocking noise on cold start...didn't hear it till today and I just bought it used on saturday! Is this typical? Wife took it down the road and I could hear it as she passed and it has been running a few minutes by then. I put regular fuel; it is a flex fuel engine. 59,000 miles. Not sure if it stopped later or not.

 

My 2006 with L33 aluminum block taps/knocks as well but this was a little different. The 6.0 in my 05 2500 work truck makes no noise at all! What might it be? Thank you.

RyanbabZ71 Senior Enthusiast

RyanbabZ71

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  • Author
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Not sure what fuel the L33 takes as this thread is for the L9H version. I assume premium and since you used regular could be spark knock. Run it empty and put the right gas in it and see what it does

 

 

Ryan

NemesisC5 Enthusiast

NemesisC5

Posted
Posted

I have an exhaust leak on the driver's side. I thought it may be leaking at manifold, but dealer said the problem is usually the first joint. I checked to make sure the 3 bolt flange was tight. It may not be as bad now but still leaks. Exhaust wrap?? Would a small leak cause less low-end torque?.....

 

 

 

Johnny

 

 

I have an 11 1500 6.2 with 98k miles. My exhaust manifold on passenger side was cracked and they replaced it under warranty. The exhaust leak did not affect my low end power.

Also replaced broken engine mount under warranty as well. Happy owner!

  • 2 weeks later...
rutwad Enthusiast

rutwad

Posted
Posted

My 2011 runs pretty rough when I first crank it. Other than starting right away, you may even think it's not fuel injected the way it runs for a couple of seconds. Then it runs smooth with only a small yet aggravating exhaust leak. No codes. I'm guessing this isn't typical.

401 YJ Enthusiast

401 YJ

Posted
Posted

I need some advice. I just got my American Racing Headers and am looking forward to installing them in the near future. I just want some pointers on getting them to seal and stay sealed. I have only put headers on my old Jeep and the were always leaking. These ARH's are way better quality then anything else I have ever had but any help would be great. The aluminum heads worry me too. Do I put anti-sieze on the bolts? How tight do I torque the bolts? Any info would be great.

RyanbabZ71 Senior Enthusiast

RyanbabZ71

Posted
  • Author
Posted

Buy new stock ac delco gaskets. Didn't use anything else. Did this with my camaro. Not sure what torque is for the trucks.

 

 

Ryan

401 YJ Enthusiast

401 YJ

Posted
Posted

Thanks for the quick reply. I have them in hand now. Wish me luck.

RyanbabZ71 Senior Enthusiast

RyanbabZ71

Posted
  • Author
Posted

Post some after video. Headers would be awesome

 

 

Ryan

NemesisC5 Enthusiast

NemesisC5

Posted
Posted (edited)

I still have factory exhaust on 2011 Silverado 1500 with the 6.2. Been looking into headers and read a thread on Performance Trucks of an owner removing LT headers because of mechanical noise made more audible after installing headers. Several other members chimed in and agreed they have the same noise but most were not concerned. I have a C5 Corvette with headers and the they definitely bring out more noise from the internals but the previously mentioned thread on Performance Trucks indicates that the noise on our trucks is louder than other engines / apllications. Can anyone here comment on this?

Edited by NemesisC5
Jsdirt Senior Enthusiast

Jsdirt

Posted
Posted

I tell people if your worried about noise, leave your exhaust stock.

  • Like 1
NemesisC5 Enthusiast

NemesisC5

Posted
Posted

I tell people if your worried about noise, leave your exhaust stock.

 

Not an answer to my question, I'm asking about mechanical noises on the L9H being louder than other engines.

 

If you can't help with contributing helpful information please refrain from "if God meant for men to fly he would have given us wings" type of answer.

Jsdirt Senior Enthusiast

Jsdirt

Posted
Posted (edited)

Don't get your nylons in a knot - I misunderstood your question! GEESH ....

 

 

BUT .. headers are inherently going to make the vehicle louder, so ....

Edited by Jsdirt

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