Howdy all, I have a 2005 1500 5.7 hemi and was wondering about what size gears I should look into getting. I have 35 inch toyo open country tires in 18 inch rims, a spectre CAI, flowmaster box, and I'm looking at either a diablo predator or bully dog programmer. I'm not sure what size gears are on it, maybe 3.67? I'm more interested in speed than towing. Any other suggestions on upgrades or programmers? I can't figure out how to put a pic of my truck on here but if I ever figure out I will.
Thanks!!

-Huntman

 

What do you mean by "Speed" .....quick off the line? then 4.56's or 4.88's or high top speed? then keep whatever gears you have, which could be 3.55's or 3.92's. You really should figure out what gears you have....you can open a pumpkin cover and count the teeth of the ring gear and pinion gear and do the math.

 

seeing it's an '05, there is a good chance the lid of your glovebox will have a sticker which is still readable.. that will tell you your build and your gears..

 

and, one more sumpthin: with the tranny in your truck- lower gears will really only be felt in first and second gear.. with your tires- 4.56's will be the best selection to get 'em rolling faster, and make life easier on your tranny.. you'll barely know your gears are lower once you hit fourth..

 

I can't find anywhere that it says the gears. And I guess I'm looking for off the line speed. Would the bigger gears slow me down more at top speeds? About how much should it cost to get these changed? would it really improve performance that much? Obviously I have no knowledge of this haha. Thank y'all for the replies!!

 

Is it a 4x4 or 4x2? makes a big difference both in gear options and cost.


When they say you lose top speed by higher numerical gearing, it's because your rpm's will be higher at a given speed. Which is why towing is enhanced and "hole shot" is dramatically increased as you reach the powerband faster and with less throttle pressure. Because you are at a higher RPM, you'll reach redline or "top out" at the same RPM as you used to, but your speed will be slightly lower at this RPM.

It's not day and night. I'm not sure because I'm all about torque and low end but to throw a number out there, let's say you reach your rev limiter when you are at 140 mph with 3.92 gears, you'd probably reach the same RPM at about 132 mph or so with 4.56 gears.

Most people are unconcerned with the slight loss of top end speed as it's hole shot they seek...

 

It's a 4x4. And thanks hammer that makes a lot more sense. Usually anytime I race someone or am having fun with buddies it's always short distances so off the line speed or low end speed would be more important than how fast I can reach my top speed.

 

Local shop by me charges $600 per axle for gears, install kit and labor. But if you want to really lock up, you better have them throw a good LSD in the rear diff when they have it open, something with a decent bias ratio...

4.56 is the max for a 4x4, 4.88 is available for the rear axle, but not the front. So, just don't race any 4x2 Ram owners, could be they got 4.88s and will beat your a$$ off the line, LOL...

 

hey drew how you like the 4.56 gears in ur rig....i have the same type of rig and im trien to decied what i want to regear it too

 

the 4.56's make all the difference in the world man.. I can pop it and get rolling with ease whether I'm loaded down or not.. and my gas mileage hasn't taken a hit at all.. I know the tranny is much happier- it doesn't search for gears anymore.. It's easily the best mod I've done, but it's also one of the more expensive too..

I don't think anything but your bank account would regret you doing it.