Advice buying a new to us 2012 Tahoe

[Junior1dad6888]

Looking at a 2011 Tahoe with the 5.3 flex fuel (whatever that means) 4x4. The wife has a '04 with 80k but frame has rusted and we love it....a whole other topic on that....anyway looked at this Tahoe with 104k miles. Super clean. She putted around and loved it. I took over and when I hit the gas at 35 mph or so it bogged....just sat there.... and then kind of accelerated. Her '04 is no speed demon but does not have that bog. Is that normal??? Thanks in advance for opinions!!!

 

[Doubeleive]

Depends, did it only do it once?

 

[swathdiver]

FlexFuel means you can E85 in it. Torque Management is the system GM uses to preserve the life of the transmission from lead feet, the motors sometimes feel sluggish and the shifting not so smart or on point. Let's say you get moving, get up to 30-35 and then partially nail it, it's not going anywhere, the computer did not tell the transmission to downshift unless you push the gas pedal down further.

A BlackBear tune cures all of that nonsense and makes a great truck a fantastic truck to drive.

 

[Junior1dad6888]

It did it every time. Full throttle to the floor like passing on a 2 lane. Didn't really have a miss, more of a stumble, bobble, not go anywhere. If I had to get moving to avoid something I would have gotten creamed........did it every time I tried massing it to the floor.

 

[swathdiver]

It did it every time. Full throttle to the floor like passing on a 2 lane. Didn't really have a miss, more of a stumble, bobble, not go anywhere. If I had to get moving to avoid something I would have gotten creamed........did it every time I tried massing it to the floor.

Something isn't right then. If you really like it and they let you, take it to a GM trained mechanic with a Tech2. A Chevy/Cadillac/GMC dealership preferrably, let them run a scan and see what's wrong with it. Then you can decide whether or not to buy it.

Could be dirty air filter, mass air and throttle body needing cleaning. Might need new plugs and wires or something more sinister that only the scan tool can see.

 

[Doubeleive]

is this at a dealer of some sort or private party? what is the mileage?

 

[Junior1dad6888]

Miles are 104k. It is at a Chevrolet dealer on their used car lot. My wife likes it. Me...not until it runs better. Worried about the drivers weather-stripping rusting and coming apart also but figure that is probably normal for a 6 yr old.....

 

[mikeyss]

I came from an 05 Tahoe and I agree, downshifts never miss a beat. I then got my 09 tahoe and before I had it tuned by Blackbear, it got some getting used to the strange 'moods' the 6 speed auto has. With that said, at 30-35mph, the stock tune won't allow the trans to go back down to 1st gear. Its Because 1st gear is low, 4.03:1 and downshifting at 30mph would cause your rpm's to go over 5000rpm. Because of it not downshifting, the engine is bogged into 2nd gear which is 2.36:1, so the 5.3 is under it's power band. To make matters worse, the Tahoe you're looking at may even have 3.08 rear gears, further bogging down the 5.3.

 

[gooffeyguy]

Let's not forget, drive by wire vs throttle cable. Without a tune there will always be a slight hesitation/delay when mashing the gas.

2001 Yukon SLT
2011 Yukon Denali

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[Junior1dad6888]

It was more than a slight hesitation. Probably could have counted to 5 before it went anywhere......dealer "texted" yesterday and said service found NO PROBLEM. Did I realize that I had the AC on? That was probably all I felt. I guess I need to go drive more of them to see if that is "normal"?? I like the shift strategy explanation, that makes sense to me. Seems like an excessive time period for a delay. The bog wasn't just a "wrong gear start" slow acceleration feel. It felt like it was doing nothing, then took off. Thanks for all the ideas!