Yeah a few weeks agoI was having the same problem with my engine light staying on soI called Onstar and had them run a diagnostics on it and they saidI had a problem with the emissions system.SoI called my Hummer dealership whereI got it which is in Memphis,Tn and they said that they have had a lot of problems with that and said to bring it over and they said any H3 that was built before this certain time peroid that they had to repair,so they replaced a whole new cylinder head in it for me for free since it is under 50,000 mile warranty and I only have a little over 13,000 miles on it and they loaned me a brand new 07 Chevy Tahoe which I only drove for a day since they had my H3 already repaired and btw I totally like the H3 a lot better than the Tahoe,the Tahoe did not have as smooth of a ride as my H3 does and does not stand out like the H3 either,and ever since I got it back i've noticed it has more power and better gas mileage too.Very satisfied with those guys at Sunrise Hummer in Memphis,Tn.

 

IKer,your H3 seems to be off the charts when it comesto gas mileage. Not even my H2 did that type ofmileage. Ican average about 300 on a tank in the city and was doing about 200 miles every 3 hours on the road (65-70 mph) recently during a road trip (which is when my valves blew out [sm=boosign.gif]).

Seriously, if you're getting less than 15 mpg, you need to check that puppy out.

FDT

 

I have had it checked...by two dealers and they both said "due to larger tires" You can never expect a dealer to fix ANYTHING that they have to actually troubleshoot.

 

OK, at least there's some sort of explanation...larger tires do decrease your gas mileage, however, I'm shocked at how poor you're really is. How big are those bad boys...?

Hey, not to change the subject, but does anyone have a copy of the actual service bulletin that the dealers got regarding the H3's valve issue? I'd really like to read it for myself...

FDT

 

There ain't a certified TSB yet that I know of...It's mainly a fix as they are found sort of Champaign...Kinda hush, hush sorta chit!

 

I have 35x12.50x17's. But my mileage stock was never over 12 or so. going to 35's should lower your mileage by roughly 10%, not down to 8.5mpg. I'm just gonna beat the hell out of it till I break something real good and then the dealership can fix it.