Topic: SWAPPING FROM 31s to 32s or 33s or NOT ?

[quicksand]

Like many others we are tight on funds yet we have a long wish list for our rigs. I currenty run a 2in BB along with 31 BFG muds. I was thinking of bumping up to 32 or 33x10s. My LiL rig is pretty fast right now with its current mods under the hood and I am a daily driver. I have no complaints. But my concern is if I go a little bigger by adding a body lift or getting a real spring lift with bigger tires, how much power will I lose with 32s, or 33s? I can not get a gear change right now. Then do I have to get 8in wide rims or can I squeeze 32s on my 7in rims?  It just seems like if I choose to do a little more one thing will lead to another. Bigger lift,bigger tires, bigger rims, lower gears. I do not want to regret anything such as lose of power, or drive line issues. Either wait till I get the funds to do it all, or do I just leave it as is. I guess maybe it just cost to run with the big dogs.  I need to install my discos  and see what my 31s can do with the BB, and hope I do not rip off a pumkin or somthing.

[Jeffy]

If you don't want to do everything else that is required with 33's then stick with 31's.

[quicksand]

Well said, I will one way or the other. You are correct, step up to the plate and do it right, or stay with 31s. Thanks

[quicksand]

Question will my 4.10 gears handle 32s , and would it be a big difference in power loss or minimal? Also can I but 32s on a 7in rim?

[chrisfranklin]

Question will my 4.10 gears handle 32s , and would it be a big difference in power loss or minimal? Also can I but 32s on a 7in rim?

I've got 31MTs on 4:10s and I'm not in bad shape with that until we're talking highways on grades.    Dropping to 4th isn't a big deal for that.  But I have found myself having to drop to 3rd on more than a few occasions just to keep up to speed in the slow lane.  Zinging along at 4000rpm in 3rd doing 60- something for any length of time is no fun.  Getting some headers and would like to believe that that and an efan will help the 4banger along under load on the highway; rather regear 4:88s if I go to 33s on the next tire change

[Bounty Hunter]

As much as it sounds like your enjoy your jeep's current performance level, I would recommend NOT going up in tire size.  Your performance will drop off considerably.  Wait until you can regear.

[4BangerTJ]

I agree. As much as you want the bigger tires you will regret the power loss unless you regear. As for your answer on the I'm change you can butt a 32 or 33 on a 7 inch wheel depending on the width of the tire. I wouldn't try a 12.50 width on anything but an 8 inch width but a 10.50 can fit on a 7 inch width wheel. Remember that the wider a tire you stuff on a wheel the more it will change the shape of the tire from a flat surface you are rolling on evenly to an oval shape surface causing you to wear out the middle of the tire faster than the outside. Hope this helps.

[quicksand]

Well it looks like I am gonna wait till I can regear for bigger tires, because I really do enjoy my current jeeps power right now, with all its mods under the hood. My favorite mod is the custom TB spacer and that bigger TB. Your right about that Mr Bounty Hunter, after the throttle body swap I sure would hate to lose that increased power I have. Ofcourse in balance with all the other mods under there. So in the future what gear ratio would I need for 32s or 33s for a daily driver? I am looking for somthing moderate as I spend most of my time on the road, and like to do ocassiolnal offroad. What do you guys think of 33x10s ? Thanks for all the input guys.

[Bounty Hunter]

4.88 gears is the best option, nothing lower available for the stock axles.

[quicksand]

Thats all they got for my dana 30 and 35?  They do not have 4.56 gears for those axles?

[Jeffy]

Thats all they got for my dana 30 and 35?  They do not have 4.56 gears for those axles?

4.88:1 is lower then 4.56:1. 4.88:1 is the lowest you can get.

[quicksand]

Yes I knew that, my concern is that 4.88 may be to low for 33s. I do not know. I guess the question is does 4.88 and 33s but me close to my current set up. 4.10 and 31s?

[sharpxmen]

Yes I knew that, my concern is that 4.88 may be to low for 33s. I do not know. I guess the question is does 4.88 and 33s but me close to my current set up. 4.10 and 31s?

4.88 and 33 is same as stock (assuming you started at 28'' and 4.10)
Your speed to rpm ratio is directly proportional with your tire diameter and inverse to the R&P ratio (1/R&P), which means the higher the number in R&P (lower gears) the more rpm for the same speed. the larger the tire diameter the more speed for the same rpm.

To compare them you can simply do simple math like this:
28/4.10=6.83
33/4.88=6.76 (1% difference vs stock)
33/4.56=7.23 (5% difference)
31/4.10=7.56 (10% off compared to stock).

[quicksand]

Very Nice, thank you for that info and chart. That will be a big help.

[quicksand]

Is there a difference in strengh between 4.56 and 4.88 as far as breakage or longivity?