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Discussion Starter · #1 ·
I have a 2wd crew cab 07+ nnbs. I have the 3.73 open rear diff (non locking)with drum brakes. I was wondering if there was anyone with a lifted 2wd with 3.23 rear diff that would like to trade axles with me? The 3.73 gear ratio would probably be better for you if you have big wheels and tires! i am going the lowered route so I don't need such a low gear ratio. I live in the Phoenix area of Az and we could do the swap at my house. I think it would take a couple of hours to swap out the axles. Let me know.
 

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Never heard of that before....
 

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is Bi-Winning and a
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Theres really not A LOT of difference in the 2. You might as well keep the 3.73's if you are going lowered...
 

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Why the hell would anyone want 3.23's? The 3.73's are perfect all the way up to a 33" tire IMO. Unless you want to be a freeway flyer, stick with the 3.73's.
 

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Discussion Starter · #6 ·
Never heard of that before....
Yes but an easy swap!

Theres really not A LOT of difference in the 2. You might as well keep the 3.73's if you are going lowered...
Stock=revving 2300rpm at 75mph I would like to bring the revs down on the freeway. The lower (numerically) gear ratio 3.23 is taller than the 3.73 ratio which will bring my revs down

well sir your definition of A LOT and mine are very different
OK?

Why the hell would anyone want 3.23's? The 3.73's are perfect all the way up to a 33" tire IMO. Unless you want to be a freeway flyer, stick with the 3.73's.
Yes a freeway flyer, 60 miles a day. My rpms will be 13.5% lower at 75 mph. bringing the revs down to about 1990 saving me some gas!
 

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You mentioned that you are going the lowered route. Are you planning on running 20's or 22's with wider than stock tires? If so, some of those wheels can get heavy, and rolling mass can play a big part in fuel economy. The 3.73's will be better in the city with being able to use less gas pedal to get moving as well as on the highway to keep them rolling.

To use an example: My 06 2wd(see sig) had 3.73's stock with stock wheels/tires. When I lifted it, I went to 4.56's with 35" tires due to increase in both size AND weight. If only size was the issue, 4.30's would've been closer to the stock ratio. But now my new wheels/tires weigh ~40 lbs more each.

My whole point is that you probably won't see as big of a mileage increase as you might expect. I don't think that you will find anyone willing to trade anyways, being that it's more than a basic swap. The PCM(computer) will also need to be re-tuned for the new gear size, or you will get ABS and brake system lights on the dash. Whatever you do, do not pay for a gear swap, as it will take forever to break even on savings. If anything, just slow down to 70.

If you really want fuel economy, should've bought a Prius. JFWY
 

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Discussion Starter · #8 ·
You mentioned that you are going the lowered route. Are you planning on running 20's or 22's with wider than stock tires? If so, some of those wheels can get heavy, and rolling mass can play a big part in fuel economy. The 3.73's will be better in the city with being able to use less gas pedal to get moving as well as on the highway to keep them rolling.

Stock 20inch wheels and they are aluminum, So no rolling mass issues I am not changing the ratio to anything wierd since this is a stock ratio that is the standard equiptment. My truck was optioned with the 3.73 ratio. I didnt want it with that ratio but it was the only truck with the other options I wanted.

To use an example: My 06 2wd(see sig) had 3.73's stock with stock wheels/tires. When I lifted it, I went to 4.56's with 35" tires due to increase in both size AND weight. If only size was the issue, 4.30's would've been closer to the stock ratio. But now my new wheels/tires weigh ~40 lbs more each.

No offense but blah blah blah

My whole point is that you probably won't see as big of a mileage increase as you might expect. I don't think that you will find anyone willing to trade anyways, being that it's more than a basic swap. The PCM(computer) will also need to be re-tuned for the new gear size, or you will get ABS and brake system lights on the dash. Whatever you do, do not pay for a gear swap, as it will take forever to break even on savings. If anything, just slow down to 70

My cousin has the same truck but with the 3.23 and he gets 20-22 mpg on the highway, I get 16-18 so I will see a difference. I drive mostly highway and very little city. The speed limit where I drive is 75mph so slowing down to 70 might not be a great option for ME! I know about the pcm and I can have that taken care of.

If you really want fuel economy, should've bought a Prius. JFWY
bump
 

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South Carolina Gamecock
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Keep your 3.73. Swapping out for something taller is going to be waay too much trouble imo, and you won't see a big improvement. I have 3.73 on OEM 265s, and I'd lose my mind if I had anything taller.
 
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