Ok I have been doing some research and the different gears and I am wondering if it would be a good idea to do this. My truck has the 3.36 gears I am wanting to drop it down to the 2.94 gears I do not tow and thing much and the 3.36 gears is killing me with gas millage. I have always wondered why some people get 15-17 mpg and some 9-12. I am currently getting 9mpg. Why are the advantages and disadvantages of swapping the gears like this? I know it would improve gas millage but would it hurt me in performance?
Ring and pinion gear
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If you're getting 9mpg, I have to ask if you're stock, or lifted/big tires, or what your driving is (city or highway).
9 is low. I have a 2011 Pro4x with the 3.36 gears, and I'm getting about 14mpg combined city/highway. Only change from stock is the E-rated BFG TA/KOS tires with which I replaced the OEM P-series tires. These weigh about 20lbs per tire more than the OEMs and took away about .5mpg.
You're not going to get "good" mileage regardless, and I suspect it would take forever to recoup the cost of changing your gears, and you're likely to lose cruise control.
9 is low. I have a 2011 Pro4x with the 3.36 gears, and I'm getting about 14mpg combined city/highway. Only change from stock is the E-rated BFG TA/KOS tires with which I replaced the OEM P-series tires. These weigh about 20lbs per tire more than the OEMs and took away about .5mpg.
You're not going to get "good" mileage regardless, and I suspect it would take forever to recoup the cost of changing your gears, and you're likely to lose cruise control.
I have nitto g2 tires with a hypertech programmer set on 91 and a airaid cai. I've read where changeing the gears can get you up to 6 mpg but common since says it's not that easy to get that much more mpg. But does the 2.94 make the trucks faster on over all but the 3.36 is fasterrible on take off?
Already changed the front calipers I will change the back soon and I mean I know it'll save something in mpg cause the rpm will be lower but I highly doubt it'll be the 5-6 who knows tho. Theirs got to be a reason why the non tow package trucks are getting more mpg then me and that's the main difference is the gear.
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Long before I started into the expense of changing out to a lower gear, I'd be looking at wheel bearings on the front, brake calipers, and how much extra crap I was carrying around. I'd also take a good long look at your driving style. I suspect if you're honest with yourself, you stick your foot in the throttle more than you have to. Do some reading up on how to improve your mileage, and put those things into practice before you start dumping money into expensive mods. And expect about 1.5mpg better with the 2.94s, not 5-6. If you're 4wd, lifted, and heavy tires, you can knock off about half to 1mpg for each of those things. You may also have an issue where your truck is not responding well to the CAI you have on it.
I'd be willing to bet if you swap the gears, you'll get 10mpg, with no other changes, and you will lose some bottom end power.
I'd be willing to bet if you swap the gears, you'll get 10mpg, with no other changes, and you will lose some bottom end power.
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That cai isn't helping your mpg. Like dubyam said
I am confused right now I have been doing a lot of driving in the last two days driving like I normally would and so far I at 105miles a little below quarter tank of gas I decided to plug in my computer today to it while I was driving and my maf sensor is all over the place my bank one 02 sensor goes from .8 to 0 to -.8 and the maf sensor jumps all over the place going the same speed and same rpm.
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If you're reading your Bank 1 Position 1 O2 sensor, it should be pegging back and forth from 0 to .8-.9 pretty much in an sine wave if you graphed it.
But your MAF is acting funny. Get some MAF cleaner and give it a go, and consider whether or not you have leaks in your CAI, or a dirty filter.
What are your short and long term fuel trims at idle, 1500, 2000, and 3000? Should be a short and long for each bank.
But your MAF is acting funny. Get some MAF cleaner and give it a go, and consider whether or not you have leaks in your CAI, or a dirty filter.
What are your short and long term fuel trims at idle, 1500, 2000, and 3000? Should be a short and long for each bank.
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Ignore the gauge. Hand calculate your mileage.
Miles driven divided by gallons used. Fill the tank. Reset the trip odometer. Drive all week. Get gas. Calculate MPG.
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Based on the richening of your mixture, you might have cracked manifolds. You're not super rich, though. But at idle, you're running 13+ percent enriching, so your sensors are telling the motor you're lean.
You didn't say whether this is bank 1 or 2, and you should have fuel trims for each. Knowing the splits will help understan eats going on.
My guess is, your CAI, driving style, and tuner are killing your mileage, but you might have a cracked exhaust manifold.
Regardless, gears are not going to resolve this, so don't waste your money.
You didn't say whether this is bank 1 or 2, and you should have fuel trims for each. Knowing the splits will help understan eats going on.
My guess is, your CAI, driving style, and tuner are killing your mileage, but you might have a cracked exhaust manifold.
Regardless, gears are not going to resolve this, so don't waste your money.
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And if your fuel trims are jumping all over the place, that's not right. At a steady rpm, they should be pretty constant, though they will fluctuate from one throttle position to another and at different RPMs. They also read a little differently under load, so maybe have someone else drive and you write down the numbers at specific, held RPMs while driving.
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