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Discussion Starter · #1 ·
ok i have 33's right now and will have 35 in the future when i get more money saved up. my question is should i go with 4:56 gears now and then i can add the 35 later to compasate. the only reason i want to do gears now is cuz i smoked my tranny and dont want to do it again. also if anyone ran 4:56's with 33' let me know what you were tachin at on the freeway. also gas milage. i know its a truck and blah blah but it is still my only trasportaion and i need to worry about these things. thanks guys.
 

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Justin,

You probably won't be happy with 33s and 4.56s. 4.10s are enough for 35s, but aren't SUPER low. If your not interested in rock-crawling, and don't feel you need the extra-low of the 4.56s, then you'll probably be ok with 4.10s.

Even with 3.92s, I'm pretty happy with my 35s and performance, but for continually driving on Hwy9, 4.10s or 4.56s would be a LOT better.

I figure 2700 rpm in OD at 70-75mph with 4.56 gears and 33" tires...

Ouch...

2450 with 4.10s.

when you go up to 35s in the future, those will drop to 2300 with 4.10s, and 2550 with 4.56s.

I'm using my 3.92 gears, 35" tires, and highway cruising at 70-75mph at 2200 rpm or so to come up with these numbers.

Oh, and I get crap mileage. 12 or so. Would go up with teh larger gears, because i do so much mountain driving.
 

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How long is it gonna be before you get the 35's? If its not long than I would go with 4.56's.
 

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Yep.

The larger your tires, the lower the rpms you need to go a certain speed.

[( tire size * pi ) * (engine rpm / OD ratio / axle ratio) * 60 ] / inches per mile = speed...

But it's not coming out right... I seem to be about 10% off or so, but the units work out right...

[(35"*pi)*(2200/0.69/3.92) * 60min/hour ] / 63360 in/mile = 84 mph?

I don't think so... I run 2200 rpm on the highway all the time, and am only aorund 75...

Any problems with my math, guys?
 

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i have 33's and 4.56 gears and i like them. i would go ahead and get 4.56. as far as rpm on the highway i turn about 26 or 2700 at around 75mph. depending on how often you drive this fast its not a big deal.
 

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Definitely go with the 4.56's if you are planning to run 35's later on. My truck is a dog with 35's and 4.10's. The slightest upgrade or headwind and overdrive is just a memory. You will be glad you did.
 

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Discussion Starter · #10 ·
cool thanks guys. i am going to go with 35's when i need to buy tires. i just cant see buying tires when i dont need them yet. so probly 6 months or so till i get tires. i dont plan on rock crawling with a 24k truck. so i guess i am thinkin of the 4:46's sinse i am really nervis about puttin any stress on my tranny. when i am done that thing is going to run so cool it will freeze dammit. thanks for the help now i just need to find someone to do the install cheap or i might try my self. well see
 

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yeah I was talking to you 98dodgeram
 

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Definetly go with 4,56, I had the same setup that you are planning (33´s and 4,56), and my truck perform really good and both on and off road, now I have 35´s and it still ride nice. 2250 at 60.
 
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