Moving up a tire size?

[Jesse]

I am currently on 31" tires. I was just wondering what are the advantages & disadvantages of going up tire sizes? I may sound clueless about these things, and that's for good reason, cause I am. But I'm trying to learn with your help!

 

[Bounty__Hunter]

For every inch increase in tire size, you're only gaining a 1/2" increase under the axles and under the belly skid. When deciding on tire size, take into account your axle gear ratio and how the larger tires affect your highway performance as well as your crawl speed offroad.

 

[Jesse]

I have stock gear ratio, how WOULD putting 33's on affect my highway performance?

 

[xt master]

If you have a 4 banger it wont be to bad.If you have a I6 you will never see 5th gear again if your jeep is a standard.Also the advantage of larder tires is the C00L factor.:lol:

 

[SteelHeadz]

One of the advantages would be your ground clearance like Bounty said. If you have an auto. trans. , this will affect the shift points as well if you dont get your speed sensor calibrated to the actual speed. Find out what your gear ratio is and look at a chart for the optimum tire size.

 

[southtj]

If you have a 4 banger it wont be to bad.If you have a I6 you will never see 5th gear again if your jeep is a standard.Also the advantage of larder tires is the C00L factor.:lol:

I think that should be the other way around.

 

[Sine Deviance]

I think that should be the other way around.

It should. I6 will be okay for the most part. I4, you'll never see 5th again. I already have a hard time keeping it rolling in 5th gear and I'm on 31's.

 

[Jesse]

I have a manual transmission. & how would I find out what my gear ratio is? :redface: (please don't laugh at me... )

 

[SteelHeadz]

Look at your differential cover. There should be a metal tag attached to one of the differential cover bolts. The possible ratios are 3.07, 3.55, 4.10 .

 

[blown XJ]

3.55 and 33s isnt to bad with auto. if you have a 6cyl you most likely have 3.07 gears. i had 3.07s with 35s for a while i could never use 5th. but it was ok. its hard on your clutch though

 

[HiHood]

Look at your differential cover. There should be a metal tag attached to one of the differential cover bolts. The possible ratios are 3.07, 3.55, 4.10 .

This tag will have the number of teeth on the pinion and ring gears. for example mine say 43/8 so I have VERY low gearing of 5:38 to 1. I get this by dividing 43 by 8.:bomb:

 

[Jesse]

3.73 maybe? There was one tag that talked about the fluid i should use, the other had a list of numbers that looked like this:

111929AB
3 735993

didn't see anything between the 3 & the 7 on the second line.

 

[HiHood]

the tag should be at about 7 o'clock position and held on by a diff cover bolt.:shades:

 

[Jesse]

Here is a picture of my rear diff. Just took it, just for you!

 

[jfrabat]

It should. I6 will be okay for the most part. I4, you'll never see 5th again. I already have a hard time keeping it rolling in 5th gear and I'm on 31's.

I have 4.88 and 33's, and I rarely see 5th gear on my 4-banger... 4.88 were AWESOME with 31's, though, so 5.13 would be ideal in a 4-banger with 33's (of course this means 2 new axles, since both the D35 and D30 max out at 4.88)

 

[bootguy]

So I am in the same boat. have a 94 wrangler 4 banger and automatic. How can i go about getting the shift points corrected. and also the speedo.

 

[SteelHeadz]

Here is a picture of my rear diff. Just took it, just for you!

You have a 3.73...

 

[Jesse]

Look at your differential cover. There should be a metal tag attached to one of the differential cover bolts. The possible ratios are 3.07, 3.55, 4.10 .

You have a 3.73...

Is 3.73 rare? Is that why it wasn't in the original possibilities? or did you just not think of it? I promise I'm not trying to point out faults, or cause problems. :redface:


To sum up what I have: 3.73 ratio. Inline 6. Manual transmission. 31" tires. No lift that I know of.

Thank you everyone who has responded to this thread.

 

[88Wrangles]

What are your plans for the Jeep? Would re-gearing be a possibility? And will you be wanting to go to larger than 33" tires in the future and a lift?

 

[jfrabat]

So I am in the same boat. have a 94 wrangler 4 banger and automatic. How can i go about getting the shift points corrected. and also the speedo.

Mine is manual, not auto; but you should defenetly regear and correct the speedo gear as well...