re-gearing in older posts on here. I eventually wanted to get a leveling kit and run 285's. Now I know that this would make me really sluggish at low rpms, but here's my dilemna... I will probably be doing a fair amount of highway driving until my wife gets a new car (we'll live about 250 miles from most of our family). Getting new gears would be good for the bigger tires, but with all that highway driving, I feel that my gas mileage will suck with, say, 4.10's or 4.11's. Would I be better off to bump to like 3.73? I know that isn't much over 3.55, but then again, the 285's aren't that big. According to the calculator I used at dirtroadmagazine.com, to switch from 245's (stock) with 3.55 gearingto 285's, a gear ratio of 3.82 would be perfect. The difference from these two (3.55, 3.82) to 3.73 would be 0.18 (3.55) and 0.09 (3.73). The 3.73's would be much closer to what it should be, but would it be worth the cost? Also, can I get 3.82 gears?

 

I ran 4.10's with my 285's, and thought they were perfect. Good low end ummmph, but very acceptable at highway speeds. I got 16 highway/14 city with that combo, best I ever got. Even better then I got when I had 265/3.55 combo.

 

Is there anything in between that I could look at? Maybe 3.92's? Also, do I have to switch out the front and rear or just rear? Who sells good gears for the Ram? Sorry for all the questions...

 

You could get a 3.90/3.92 (it's a 3.90 for the rear, 3.92 for the front). With a 4x4, yes you need both front and rear. If you don't, you've just turned your truck into a 4x2. Check out Randys Ring and Pinion.

 

Thanks a bunch, man.

 

I'd switch to at least 4.10 if I were you. It's not worth the money to go any less than that. Think about how much gas you're going to have to save to make up the $1500 you're going to spend on a gear swap. Besides if you ever want to run 35" tires the 4.10s will push them, but 3.73s you'll be spending another $1500 to have get re-geared again.

 

I have 4.10's with 35's now, and i'm regearing again.[:@]

 

4.10s with 35s is more liveable than 3.55s and 33s [:@]

 

I have 3.55 gears and 245/75/16 tiresand im definitely thinkin about swappin the old gears for some 4.10's

Im going to do my plenum soon with the Hughes kit and Im gonna see if that helps the motor out, But right now im getting like 11 MPG with the current set-up on the highway...........im very dissapointed........Im hope the plenum fix brings back some power and gas mileage

 

From what I read on older posts about this, even though the 4.10 would easily turn the 285's, it would also cause a higher rpm level on the highway, leading to worse gas mileage. That's what I based my thought off of... If I do re-gear, it will be either 4.10 or 3.92/3.90. Keep in mind that I will never be going bigger than 285's.