Tahoe 6.2 with 10 speed milage issue Buyer remorse

[67RS427]

just bought A Tahoe rst with 6.2 with ten speed transmission the mpg are bad is it cause the engine is new . Having buyers remorse I been told the 6.2 is a bullet proof engine with the ten 10 speed . What mpg I should I be on I. Doing almost 9 mpg or 8.5 .

Take it in for service, something is wrong. My 2007 AWD Yukon Denali 6.2L/6 Speed got 12-14mpg City with 150k miles on it. I put a ZL1 supercharger on it, made 600-650hp and it still got 10-12mpg driving like an *******. I recently pulled the 6.2L and built a forged/stroked iron block, 402" with ported blower, 102mm throttle body, cam, 3k stall and so much more. I'm making 850 to 900hp at the crank. I drive it like I stole it and I'm AWD. Driving like an ass, I still get 8 to 9 mpg city and 14-15mpg on the freeway. Something is wrong with your transmission not shifting into all the gears or the motor is running very poorly. Possibly a bad plug wire or coil... Take it for service, that is not normal for a 6.2L/10 Speed regardless how hard you drive it.

 

[RST Dana]

Take it in for service, something is wrong. My 2007 AWD Yukon Denali 6.2L/6 Speed got 12-14mpg City with 150k miles on it. I put a ZL1 supercharger on it, made 600-650hp and it still got 10-12mpg driving like an *******. I recently pulled the 6.2L and built a forged/stroked iron block, 402" with ported blower, 102mm throttle body, cam, 3k stall and so much more. I'm making 850 to 900hp at the crank. I drive it like I stole it and I'm AWD. Driving like an ass, I still get 8 to 9 mpg city and 14-15mpg on the freeway. Something is wrong with your transmission not shifting into all the gears or the motor is running very poorly. Possibly a bad plug wire or coil... Take it for service, that is not normal for a 6.2L/10 Speed regardless how hard you drive it.

How some pictures of that big rat motor!

 

[Jorge1313]

Take it in for service, something is wrong. My 2007 AWD Yukon Denali 6.2L/6 Speed got 12-14mpg City with 150k miles on it. I put a ZL1 supercharger on it, made 600-650hp and it still got 10-12mpg driving like an *******. I recently pulled the 6.2L and built a forged/stroked iron block, 402" with ported blower, 102mm throttle body, cam, 3k stall and so much more. I'm making 850 to 900hp at the crank. I drive it like I stole it and I'm AWD. Driving like an ass, I still get 8 to 9 mpg city and 14-15mpg on the freeway. Something is wrong with your transmission not shifting into all the gears or the motor is running very poorly. Possibly a bad plug wire or coil... Take it for service, that is not normal for a 6.2L/10 Speed regardless how hard you drive it.

I took it in for service they said drive a few gas tanks plus the car is new not even broken in gm says a car is broken in after 300 mile on it service department made a report on it but the they hooks up to the computer and everything seems right nothing bad said everything is I check. Soemeon to,d me computer is still adjusting to way one drive to early to tell

 

[67RS427]

How some pictures of that big rat motor!

My build thread http://www.tahoeyukonforum.com/thre...t-outta-hand-really-quick.92148/#post-1099031

and my Instagram: 67RS427_twinturbo

I took it in for service they said drive a few gas tanks plus the car is new not even broken in gm says a car is broken in after 300 mile on it service department made a report on it but the they hooks up to the computer and everything seems right nothing bad said everything is I check. Soemeon to,d me computer is still adjusting to way one drive to early to tell

Still doesn't seem right to me... During the Woodward dream cruise here in Michigan I was WOT off every single light, doing AWD burnouts and launches and sitting idle in stop and go traffic for hours every day and still got 6.5mpg avg. Long term fuel trims don't take that long to learn in to where you would see that kind of poor mileage. You would literally need to be ripping on that thing constantly with no freeway driving or cruising. Try resetting the instant AVG MPG and see what it is while your cruising. Check the miles per gallon yourself by resetting a Trip OD and calculating how much fuel you put in the tank. The computer reading could be off for a few reasons.

 

[JohnH57]

Just wanted to say that way back in 1987 I bought a brand new SS Monte Carlo and for the first approximately 5000 miles the mileage and performance had me wanting to return the car and then almost overnight the mileage almost doubled and it would blow the tires off at will. Hope that happens at some point for you. 6.2 Tahoe should be a sweet ride.