Pinging

[BIG HUMAN]

Newbie - first post.

I just purchased a 04 5.3L Hoe with 42,000 miles on her. Use to be a F#$( guy, but have since seen the light with this vehicle. I have two minor issues fuel economy and a deep pinging(see below). I know why I get bad fuel economy to heavy of a foot. Love the power compared to the Expedition that this hoe replaced. I plan on upgrading: a cold air intake and changing the muffler. Any other ideas???

When I bought it I did not notice anything abnormal. But the next day I noticed a deep pinging coming from the Catylic convertor. While it is running it happens and after I ahut it off it continues. The dealership says that that is normal due to the expansion of the metal in the CC. At first I believed him. Now after listening for other GM truck or SUV to if they are doing it as well. I have not heard any of them do it as much as mine. In 5 minutes it will due it 3 times.

Any Ideas???

PS. Love the power.

 

[Design]

Welcome,
To your first question, there are several threads regarding the improvement of gas mileage. CAI, Exhaust, Electric fans, and all the other basic improvements will net you better MPG and after you get used to to new truck you'll drive slightly different.

The pinging may be excessive or you may just be driving it hard and heating it up a lot. I haven't read of anyone here having CAT failure on a 'hoe. I would crawl under the truck (before you drive it) and do a visual inspection of the exauhst system. Check for dicoloration due to too much heat. What kind of fuel are you using? Do you have a higher level of ethanol *cough scam cough*?

Again welcome to the family

 

[BIG HUMAN]

Thank you for the reply and I'll have to check the exhaust out.

I'm currently running 91 octane From BP/Amoco. This is after running a couple of tanks or 87 as well as 89 with 10% ethanol. I was told by the dealership not to run the ethanol, Just run 87 Octane and not to worry about it. I had problems in the past with 87 so I stepped back up to the premium. On the Expedition I would get 2 mpg better running premium. Should I run 87 or 91?

 

[HitandRunDriver]

well i've been running 87 since the truck came off the lot 98k ago and i havent had any problems....i thought 91 was mainly needed for high performance engines because of the tendency to reduce cylinder knock. Whhat problems did you get running 87?

 

[BIG HUMAN]

I had problems on a Ford and a Jeep G.C. with pre-ignition & knock/pinging during warmer months.

I ran the 87 in the HOE for 2 tanks and avg MPG according to the display was only 11.8. Switched to the 91 and went up to 12.6. not a huge gain, but a gain none the less. Same drive and speed. Switching from the Ford I was hoping for even better fuel economy then what I was getting. Which I did (10.6 in the winter months and 12.6 during the summer). I guess that I'm tring to compare to my brothers k1500 with the 5.3L avg 17 mpg, driving the same style. I understand that I have more weight which will decrease the fuel eco. I was just hoping for 15-17 on avg. that would help justify the upgrade (more power & better fuel economy).

My main concern is the pinging. I never have heard a vehicle had this many pings. I can accept, a ping after it's warmed up and while it's cooling down. But this thing pings all the time. 3 times in 5 minutes.

 

[LAP TOP GAMER]

Cool a ford to Chevy convert! I love those stories! Welcome tt the Tahoe world.

 

[greengumby]

Exhaust System - Popping/Snapping Noise When Hot/Idling

Bulletin No.: 03-06-05-008D

Date: March 05, 2007

TECHNICAL
Subject:
Exhaust Popping/Snapping Noise When Vehicle is Hot, at Idle, or Immediately After Vehicle is Shut Off (Replace Muffler Heat Shield)

Models:
2002-2006 Cadillac Escalade, Escalade EXT
2003-2006 Cadillac Escalade ESV
2002-2006 Chevrolet Avalanche, Suburban, Tahoe, Silverado, Silverado HD
2007 Chevrolet Silverado Classic, Silverado HD Classic
2002-2006 GMC Sierra, Sierra HD , Yukon, Yukon Denali, Yukon Denali XL
2007 GMC Sierra Classic, Sierra HD Classic
2003-2006 HUMMER H2

with 4.8L, 5.3L, 6.0L or 8.1L Gasoline Engine (VINs V, B, T, Z, N, V, G - RPOs LR4, L33, LM7, L59, LQ9, LQ4, L18)

Supercede:

This bulletin is being revised to add the 2006 and 2007 (Classic Only) model years and the 5.3L (L33) engine. Please discard Corporate Bulletin Number 03-06-05-008C (Section 06 - Engine/Propulsion System).

Condition

Some customers may comment on a popping/snapping noise from underneath the vehicle at idle or immediately after the vehicle is shut off. Some popping/snapping noise from the exhaust system during cool down is a normal condition.

The noise may be intermittent depending on the outside temperature and or temperature of the exhaust system at the time of testing.

Cause

As the exhaust system warms and cools, the muffler and the muffler heat shield expand and contract at different rates and may cause a popping and/or snapping noise.

Some popping/snapping noise from the exhaust system during cool down is a normal condition. The customer should be made aware that this service procedure is designed to reduce but not eliminate all exhaust system popping and snapping during cool down.

Correction

Install a new heat shield and straps on the existing muffler.

 

[Design]

Greengumby, where do you get access to the recals and TSBs? Sounds like that's his problem.

 

[BIG HUMAN]

GREENGUMBY,

Thank you for posting.

Question, Who is responsible for the cost of the repair? :umn: