0-60 in 14 seconds?

Doubeleive said:

So basic things like plugs & wires? Air filter, clean maf, transmission service? That slow of a acceleration you should be able to feel if it is the engine or transmission. If not try putting it in 2!nd gear and see if that changes anything up to 60

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Just changed the air filter and cleaned the MAF. I'll clean throttle body this week. No idea when plugs/wires were done last, not opposed to changing them out, just trying to run through the diagnostics before throwing too man parts at it. The transmission doesn't feel like it's slipping but sometimes it does make you scratch your head as to why it's in that particular gear, like when it shifts to a higher gear while going up a hill. My initial thought was air flow, it just feels like it's struggling to make power. I'll check the 0-60 in 2nd, will probably throw it in 5th and try it as well so I can see which gears it's moving through.

Fless said:

What gears are factory and what should I run ?

I have an 07 Yukon Denali and it’s lifted 7” with 22x14 on 37s , what are the factory gears and what gears should I run

www.tahoeyukonforum.com

Check the Gxx RPO codes in your glovebox to see what you have.

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GHA, GU4, and G80. Looks like the GU4 points to a 3.08

Welcome to the Forum from NH.

Lots of knowledgeable folks here who freely share their knowledge, experiences, and perspectives. Knowledge is power.

I hope that you will become a participating member in the Forum's discussions.

Pics of the truck, please.

You are already receiving sage advice from the knowledgeable folks on this Forum.

Doubeleive said:

If not try putting it in 2!nd gear and see if that changes anything up to 60

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Tried 2nd...ain't gonna lie, didn't like hearing the motor scream like that. Hard to hold the stop watch, check the speed, watch the RPMs, all by myself. Tried it again in 3rd, 0-60 in 10.83. Better, probably still not right. Tried it in D, put pulled the AFM disabler, 0-60 in a little over 12. Guess it's going to be hard to get consistent test results when it's just me, flooring it, on a back road behind work.

I had the same problem with my Tahoe. I replaced both pre Oxygen sensors with AcDelco sensors and the top end is back to normal. No codes and milage was good but the sensors were slow and old. I didn't even use a scan tool because the sensors were under $80. These O2 sensors wear out at over 100K.

10.8 isn't terrible, my 6.2l with the 6 speed will do it in 6.4 in drive. This might be hard to pin down. Probably going to take a computer diagnosis to look at everything that's going on like timing, fuel pressure, etc have you considered getting it tuned?

Doubeleive said:

10.8 isn't terrible, my 6.2l with the 6 speed will do it in 6.4sec in drive. This might be hard to pin down.
Probably going to take a computer diagnosis to look at everything that's going on like timing, fuel pressure, etc
Have you considered getting it tuned?

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When he says 'tuned', if you actually want your problems solved during the tune, it'll need to be one of those tuners that sits next to you with his laptop hooked up to your car so he can look at the realtime data and figure out what is not working properly.
Otherwise take it to a mechanic who is willing to hook up a realtime scanner to the vehicle, for the same reason.

Doubeleive said:

10.8 isn't terrible, my 6.2l with the 6 speed will do it in 6.4 in drive. This might be hard to pin down. Probably going to take a computer diagnosis to look at everything that's going on like timing, fuel pressure, etc have you considered getting it tuned?

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10.8 in 3rd may not be terrible, but I'm back up to 12-14's in Drive. I'm much less worried about the 0-60 as I am the 50-70. You get on a 2-lane behind an RV with no passing lane in the foreseeable future, that's where I need help. Currently, the planets all have to line up if I'm gonna pass 1 slowpoke and 2...not even gonna try.

I'm not looking for performance as much as I'm looking for "stock". I'd tune it if I got better MPG, but if I can get it to stock times, I'd settle for that...for now.

Marky Dissod said:

When he says 'tuned', if you actually want your problems solved during the tune, it'll need to be one of those tuners that sits next to you with his laptop hooked up to your car so he can look at the realtime data and figure out what is not working properly.
Otherwise take it to a mechanic who is willing to hook up a realtime scanner to the vehicle, for the same reason.

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Yeah, I figured it's gonna take something more realtime and interactive, it's not a plug and play situation.

Gearz said:

I had the same problem with my Tahoe. I replaced both pre Oxygen sensors with AcDelco sensors and the top end is back to normal. No codes and milage was good but the sensors were slow and old. I didn't even use a scan tool because the sensors were under $80. These O2 sensors wear out at over 100K.

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Hmmm...I hate to throw parts at something without knowing it'll fix it, but $80 isn't too bad IF the sensors aren't that hard to do. My son has an F-150, they put the rear O2 sensor on top of the Exhaust, but under a heat shield, like a big rusty sandwich...that thing was a massive PIA.