Tahoe 6.2 with 10 speed milage issue Buyer remorse

[Jorge1313]

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 .

 

[swathdiver]

Well, that doesn't seem right. They are rated for 14 City and 23 Highway for 2WD and 22 Highway for 4WD. Make sure someone aint steeling your gas or your wife isn't driving it. If I want to tank the mileage, all I have to do is let my wife drive it!

Have it checked out at the dealer. I had a minivan that we bought brand new. The motor got poor mileage and was real tight until she magically opened up at 9,000 miles. Then her mileage was great and the motor spun like a race car.

 

[CMoore711]

In my '15 Yukon XL with 6.2L and 8-Speed I've gotten down to 10-11 MPG if I drive like an *******. In normal driving conditions I'm averaging 16-18 MPG with a best of 26.7 MPG on a longer road trip.

So... If it's new and you're all excited about your new found power accelerating hard often, punching it on high on ramps to merge, etc. then I could see it.

 

[SnowDrifter]

What sort of driving do you do?

 

[Jorge1313]

I’m doing mostly city driving and driving like an old grandpa and on weekend sometime on highway I have 300 mile on it. I’m just worried about the the whole thing because I mpg or 10mpg. I bought the 2018 tahoe rst I took to service department and no errors found in computer . Dealer told me wait till engine breaks in at 3500 k is that true not sure . That why I’m here

 

[ATX 14]

I would definitely pay attention to how hard you use the skinny pedal and check tire pressure. That might be a good starting point.

 

[Doubeleive]

I'm pretty ******* the pedal, not crazy like I used to be but I have the 6.2 and 6speed and it's mixed highway/city 10.9 and this engine has approx 25k on it.

 

[Jorge1313]

I haven’t pressed it hard cause I’m breaking in the engine still manual state don’t use hard acceleration and high rpm till engine breaks in. I’m not driving it hard . Does milage improve after at dealer they told computer is still calculating milage and way I drive to adapt I don’t know if that true anyone what are your thoughts. Where would this. Engine fall in with mpg some say 16 mpg with 6.2 engine others say they get 10.9 mpg it . I’m more confused does it matter if engine is not broken in

 

[Tahoe14]

Check it at the pump at each fill up to make sure your on board computer is working properly. The Dealers have been known to be wrong.

 

[Jorge1313]

Check it at the pump at each fill up to make sure your on board computer is working properly. The Dealers have been known to be wrong.

I been doing the it average out like 9 mpgs I’m going on my first tank

 

[CMoore711]

Asking the question about “breaking in an engine” what determines if it’s broken in or not? How many miles how high of RPM should I go within the first *** miles for break-in? Break-in oil then normal oil etc. etc. Is like starting a thread about “What’s the best synthetic motor oil and what should I use?”

Google, research, read, then Google, research, and read some more.

The whole 3500 mile mark for engine break-in the dealer is telling you is the first I’ve heard of that “milestone”.

From my own personal experience; I had a brand new GM LS2 replaced under warranty in a previous vehicle at the dealership. For the first 500 miles I didn’t go above 3K RPM, then changed the oil (at the dealership), after that I continued to “Baby it” for the next 1K miles and changed the oil again (at the dealership). At about 5K miles on the motor it had developed “piston slap” so bad that GM agreed it wasn’t right and something was out of spec pulled that motor and put yet another completely new LS2 engine into my vehicle. This time I didn’t bother to “break-in” the motor or do extra oil changes in the first *** miles. Instead I just drove it as if I normally would from day 1 and changed the oil every 3K miles. It was the smoothest running LS2 I had ever felt, heard, or driven.

I wouldn’t consider myself any sort of “engine expert” or anything. Sure I know how they work, but don’t ask me to build one for you. I’m just sharing my own experience with new motors and “breaking” them in.

Don’t listen to what the guy at the dealer is telling you unless it’s in writing or in your owners manual because it won’t carry any weight for any reason. He’s just giving you his opionion... In my opinion (see what I did there?!?!)

Do some research, educate yourself, commit to a decision and don’t look back. The rest will fall into place.

Good luck with your new RST, they’re nice trucks.

 

[RST Dana]

I remember cranking up iron rat motors and letting them run 40 minutes at 3000 rpm before we test drove or changed oil. Days have changed it seems.

 

[PG01]

Asking the question about “breaking in an engine” what determines if it’s broken in or not? How many miles how high of RPM should I go within the first *** miles for break-in? Break-in oil then normal oil etc. etc. Is like starting a thread about “What’s the best synthetic motor oil and what should I use?”

Google, research, read, then Google, research, and read some more.

The whole 3500 mile mark for engine break-in the dealer is telling you is the first I’ve heard of that “milestone”.

From my own personal experience; I had a brand new GM LS2 replaced under warranty in a previous vehicle at the dealership. For the first 500 miles I didn’t go above 3K RPM, then changed the oil (at the dealership), after that I continued to “Baby it” for the next 1K miles and changed the oil again (at the dealership). At about 5K miles on the motor it had developed “piston slap” so bad that GM agreed it wasn’t right and something was out of spec pulled that motor and put yet another completely new LS2 engine into my vehicle. This time I didn’t bother to “break-in” the motor or do extra oil changes in the first *** miles. Instead I just drove it as if I normally would from day 1 and changed the oil every 3K miles. It was the smoothest running LS2 I had ever felt, heard, or driven.

I wouldn’t consider myself any sort of “engine expert” or anything. Sure I know how they work, but don’t ask me to build one for you. I’m just sharing my own experience with new motors and “breaking” them in.

Don’t listen to what the guy at the dealer is telling you unless it’s in writing or in your owners manual because it won’t carry any weight for any reason. He’s just giving you his opionion... In my opinion (see what I did there?!?!)

Do some research, educate yourself, commit to a decision and don’t look back. The rest will fall into place.

Good luck with your new RST, they’re nice trucks.

This^^^^ drive it, dont drive it, beat it, dont beat it. Just make sure you change the oil. I’ve beat just about every new car ive ever owned right out of the gate (8-10 cars and or trucks... from hondas to fords to chevys) and never had an issue.

 

[Miami-Dade]

The whole 3500 mile mark for engine break-in the dealer is telling you is the first I’ve heard of that “milestone”.

When I got my 2016 Tahoe I took it on a trip to NYC in less then a week with only 100 miles on it. Got great mileage [24-25 mpg] right off the bat. Average speed was 78MPH. Got between 500-600 miles between fill ups. I get it serviced every 5K miles with Mobil 1.

 

[Jorge1313]

When I got my 2016 Tahoe I took it on a trip to NYC in less then a week with only 100 miles on it. Got great mileage [24-25 mpg] right off the bat. Average speed was 78MPH. Got between 500-600 miles between fill ups. I get it serviced every 5K miles with Mobil 1.

The thing was I spoke with the service department the manger there. He told gm state 2500 engine and 3500 for suspension. I thought that to bolony. but I contacted gm they told me the same thing

 

[Boatguy272]

I just hit 400 Miles on our 6.2 RST today and im averging 19.2. We arent beating on it yet, but enjoy the acceleration just the same.

some of that is expressway also, but if I was at 9 mpg I would be asking questions.

My old 2007 escalade averaged 14/15 mpg and it was AWD and it was not babied.

 

[BigVette427]

Make sure you don't have it in AUTO mode (if you had 4WD and the two-speed transfer case ), make sure you're using 93 octane and not E85 (that will give you horrible mileage despite it's higher octane rating,) and at last, fill up from a different source before you go any further to rule out plain old bad gas. I average high teens around town with the 8 speed automatic and low 20's on the highway. I wouldn't say these engines are bulletproof as long as they have AFM lifters and cheap valve springs, but for the most part should otherwise be fairly dependable.

 

[MidwestMike]

As for break in, my brand new 02 got 15 mpg the day I got it.
15 years later it got 15 mpg (hate to say it out loud, but with the original plugs)

My 5.3 never "broke in" or changed the whole time I had it.

 

[Boatguy272]

Can you even run E 85 in the 6.2 ?

 

[gemarsh]

Coming from a diesel mechanic, my gas and diesel breakins consist of running them at a high idle long enough to get to operating temps while checking for leaks and adjustments. Then run them like your going to be running them at 50k-500k miles.