Sick Yukon
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Sick Yukon I have a 2001 Yukon Denali XL With a 6.0 and its an all wheel drive set up. It has 66,000 miles on it and has been well maintained. I pull a 6x12 lightweight trailer for my work and when doing so experience an extreme lack of power all around and horrid mpg at 70 mph at around 2000 rpm. The mods I am considering are true dual exhaust, a K&N cold air filter, larger throttle body, under drive pulleys,1.7 ratio rocker arms, and an electric fan. The other mod I was contemplating is purchasing a tuner and having the truck dyno tuned to maximize the other work done to the truck. With that being said, What is a realistic expectation in all around gains and or is there another option I should consider?? I am not looking for serious hp or torque gains but feel the truck should be running a lot better than it is currently. What is the best tuner to buy and is there one out there that will allow me to change settings on the fly or that has multiple programs that I can switch to depending on my needs ??? I would also consider changing the intake but have no clue as to which one would benefit me the most. I am hoping to reach my goals without going as far as replacing the heads or cam. Any and all info on known good mods would be greatly appreciated.. Also, The check engine light has not come on at all.
what is your mpg ?
don't expect to get good fuel economy with that 'suburban' which also has AWD.
regarding lack of power, all that money and parts you're thinking of throwing at the truck will do nothing if the motor has lost compression from wear (piston rings and valves). the only things i would consider throwing at it are a new MAF sensor especially if it has some kind of cold air intake setup or even a k&n air filter. And two new O2 sensors before the catalytic converters, both of which you can monitor with a hand held scanner to get an idea if they are working properly. and don't overlook a bad torque converter in the transmission that could be robbing power on the highway.
and u mentioned electric fan, if you have a mechanical fan it could simply be a bad fan clutch that's making the fan operate at engine rpm all the time which will certainly rob power and suck down gas.
don't expect to get good fuel economy with that 'suburban' which also has AWD.
regarding lack of power, all that money and parts you're thinking of throwing at the truck will do nothing if the motor has lost compression from wear (piston rings and valves). the only things i would consider throwing at it are a new MAF sensor especially if it has some kind of cold air intake setup or even a k&n air filter. And two new O2 sensors before the catalytic converters, both of which you can monitor with a hand held scanner to get an idea if they are working properly. and don't overlook a bad torque converter in the transmission that could be robbing power on the highway.
and u mentioned electric fan, if you have a mechanical fan it could simply be a bad fan clutch that's making the fan operate at engine rpm all the time which will certainly rob power and suck down gas.
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From: Schiller Park, ILL Member: #317
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