Gears

[GUNITALLREDY]

so i put 33s on my truck last month and before i had them i was able to pull 29mpg coming home from school now i can only seam to get 22mpg because the truck is constanly switching from 3rd to overdrive. so im tossed up on the 4.88 vs the 4.56. i drive the truck daily and i realy liked the punch my truck had with the 30's and the 4.11s but i wouldnt mind a little more gear with out loosing to much highway mpg. i do wheel the truck and that is the biggest problem im having, i now have to put the truck in low to get over things i would normaly do in high and on occasion i tow a 3900 ib trailer
so this is what im using to make my decision any advice?

4.11 30”tire 70mph 2256 STOCK
4.11 33”tire 70mph 2051 NOW
4.56 33”tire 70mph 2275
4.88 33”tire 70mph 2435

 

[OffTrac]

29 mpg? Are you sure?

If you're on 33s and getting 22 mpg, it's going to seem like you're bragging to a lot of people on this forum. You seem to be doing your math considering regearing, but I have to ask if you adjusted for the bigger tires?

I would say 4.10s are great for 33s, but if you're not happy with them, you'd probably like 4.56. Should be most like stock.

 

[SkyJumper]

Mileage you are posting seems high for whatever yr X you have since you left it up for us to guess.

I would not go to 4.88's for a DD and 33's. The highest I would go would be 4.56, but I would stay with the 4.11's you have now. I bet the 33's you have now are only measuring 32" or slightly higher which is only .5" in ht diameter gain over the 31's. That difference does not equal 4.88's or really 4.56's for that matter. You are better off getting re-programmed for the tire and gear size than changing gears.

 

[GUNITALLREDY]

the year of my x is a 96 eb (under my user name) it has the 4.0 in it the truck is not stock and i have performed many of the mods aldive has in his quest for 30 thread. The tires i have measure 33.1 according to the overall diameter on tirerack.com those numbers are ofcourse when the truck is in od

 

[SkyJumper]

Well to just set the record on tire sizes, the overall diameter of a tire posted is from the manufacturer. But with most all offroad tires, the tire usually comes in smaller than advertised.

But, I still would not go higher than the 4.11 gears you got for DD. I run 31's on mine with the same gear. I bought the Superlift module for programming the tire and gear size to signal the trans to operate at normal as stock shift points and speedo correction. So I still have no issues what so ever as a DD or even offroad when applicable.

 

[joecrna]

Personally, I would say 4.56's are perfect for a daily driver. $.88's if off-road or towing much.

 

[GUNITALLREDY]

Well to just set the record on tire sizes, the overall diameter of a tire posted is from the manufacturer. But with most all offroad tires, the tire usually comes in smaller than advertised.

But, I still would not go higher than the 4.11 gears you got for DD. I run 31's on mine with the same gear. I bought the Superlift module for programming the tire and gear size to signal the trans to operate at normal as stock shift points and speedo correction. So I still have no issues what so ever as a DD or even offroad when applicable.

you have 31s if i had 31s im sure id have no problem either remember im used to a truck with 30in tires and 4.11 now i have a truck with 33s and 4.11s. it made a difernce in my mpg and in my offroad capibility. just today i couldnt brake a 12 in curb in 2wd and i used to drive over this curb all the time with the 30s. i think im just going to go for the 4.56 because they bring it as close as posible to the stock ratio. i dont understand how a tuner would help my truck my speed is determind by a gear at the end of the t case i belive so idk what a tuner would do for me

 

[Blee1099]

so i put 33s on my truck last month and before i had them i was able to pull 29mpg coming home from school now i can only seam to get 22mpg because the truck is constanly switching from 3rd to overdrive. so im tossed up on the 4.88 vs the 4.56. i drive the truck daily and i realy liked the punch my truck had with the 30's and the 4.11s but i wouldnt mind a little more gear with out loosing to much highway mpg. i do wheel the truck and that is the biggest problem im having, i now have to put the truck in low to get over things i would normaly do in high and on occasion i tow a 3900 ib trailer
so this is what im using to make my decision any advice?

4.11 30”tire 70mph 2256 STOCK
4.11 33”tire 70mph 2051 NOW
4.56 33”tire 70mph 2275
4.88 33”tire 70mph 2435

Your numbers are a little skewed unless your using a gps to get the correct speed. If at stock you were doing 70 as shown on the speedo, then your doing 77 MPH now.. Basically add 10% to reflect the 3" tire difference on your mileage and on your actual speed to determine the right numbers or get your t-case speedometer gear swapped out. If your intending to stay with 33s, I'd say just keep the 4.10s. the 4.56 or 4.88 gears are nice but a little too peppy for highway use..

 

[King of So Cal]

Well my truck is a 4th gen, but I'm running 33's with 4.56's. For sure better then stock, but I wish i got 4.88's. I still have some power issues wheeling. Not even half as bad as stock, but still could be better. And I don't think 4.88's on the freeway would have been a whole lot worse for mpg.

 

[GUNITALLREDY]

well my rear end started making a clanking or clunking sound today, so i gues i have to make my decision sooner than expected