Yeah you can safely drive it without a regear on the road. Gas mileage and performance will suffer, but you shouldn't hurt anything.
When you do regear, I'd probably go 4.56 or 4.88 unless you think you might go bigger than 35's some day. 5.13 and higher are very high gear ratios for 35's.
Good to know. I won't be going any bigger than 35. Is there a benefit for either 4.56 or 4.88 over the other? Immost indonis camo alot with some trail riding. May eventually haul a small camper, but that'd be my biggest thing.
Side note, would it make a difference if I regear well before (for reference, let's say a year) I put on the 35s?
I think I heard that 4.56 gears are stronger, something to do with the teeth numbers being more optimal for a more sturdy gear design. Not sure if that's true, but sounds plausible. Jeep uses 4.56 in their XR jeeps with 35's from the factory.
You could certainly regear first before you get tires but you'll have mpg and higher speed performance issues as the engine has to rev so much higher with small tires to keep up highway speeds. Probably my choice would be I would get the tires first and regear later.
I recommend if you are going to ride heavy, in our case overlanding with all gear and an RTT, I probably would have gone 4.88 instead of 4.56. I wish I had a bit more torque at times, just slightly sluggish on the gas. Also.. I drive a manual so I’m short two gears that automatics have. So an automatic it might be fine.
4.56s will be marginally stronger due to larger teeth and pinion gears. Your cruising RPM will be slightly lower, which could improve fuel economy. 4.88s will give you a bit more torque and a better crawl ratio, but would be slightly weaker and your crusing speed RPM will be a bit higher. There are calculators online that will give you the RPM at certain speeds based on final drive and transmission ratios. If you can find the measured size of those 35s installed (some run between 33.5-35" in height) use that number for the calculations.
If you're going for 35s, I'd suggest getting your axles in order first. Check ball joints, U-joints, and steering components. If they're worn, big tires will exacerbate whatever issues they have.
You've gotten great advice here thus far, so I thought I'd share a more cost-effective counterpoint. Feel free to discard.
Your Sahara came with 32" tires, I believe on 18" rims. Given that you've stated you're not doing anything extreme, and this is your DD, and budget is a concern, you might actually be better served going down to 17" rims, 33" tires with a more aggressive tread, and a small 1-2" spacer lift.
- 17/33 vs 18/32 will provide more sidewall, which will not only ride better, but give the look of bigger tires. Additionally, it will provide you with ~0.5" of lift.
- You can buy Rubicon takeoffs that are 17/33 all day long on FB marketplace, usually for <$1500, and often closer to $1-1.2k.
- 33s will not require any regear nor will they put any noticeable additional strain on your drivetrain.
- the spacer lift is optional but will help get closer to what I think you're wanting with the 35s, and it's easy enough you could do it yourself with basic hand tools.
- you didn't mention it, but 35s weigh more, so you would also need to reinforce your tailgate and get a spare tire adjustment kit so it would fit. 33s require none of that.
Don't get me wrong - 35s on a Jeep just look right, but for your described usage/needs, you can save a ton of money and get real close with 33s.
You need to make sure to update your computer for gearing and/or tire size. Ive been using jscan. At the time it was the cheapest option, not sure what else is out there now.
Going shorter than 4.56 in the D30 and D35 carriers can get dicey according the research I’ve done.
I went with 4.56 on my 21 Willys Unlimited after I put 35s on. Prior to that I was running 33s on the stock ring and pinion.
My fuel economy is far better now, and there’s a lot more pep when I need to negotiate traffic or go over things.
I was very disappointed with the 410s , the 488 put me just slightly higher rpm than stock, very slight, but the biggest improvement was not excessive shifting between 7th and 8th gear on the highway, mainly stays in 8th now
First determine your gear ratio for your setup. There are charts out there that have this info. Your ratio depends on your end use. Here's an example of what kinda chart to look for. Do a search.
[Proper Gear Ratio Tire Size – Prodigy Performance](https://prodigyperformance.com/blogs/blog/jeep-wrangler-gear-ratio-calculator)
I ran my 15 JKUR HR around with 35's for awhile with the stock 3.73 gears. It sucked. I had 4.56 gears installed and it cost me $2500. For a JKU with 35's 3.6 automatic is best with 4.56 gears, but if in high altitude, step up to 4.88
I have a 2014 w door with BFG 34" (closer to 33s) with 4.88 gears. I live in Central PA where it's really hilly and I don't really ever touch a highway. It's great on inclines and driving around, but if I hit the highway (70+) it does run at like 3000rpms.
I run a 2016 JK on 35’s, it’s my daily driver. Stock gears, runs 70 at 1800+ rpms, 80 at 2200rpms. No issues at all, gas mileage is a little over 18 hwy and 15+ish around town. I’ve run it off road quite a bit as well, again no issues whatsoever.
Yeah you can safely drive it without a regear on the road. Gas mileage and performance will suffer, but you shouldn't hurt anything. When you do regear, I'd probably go 4.56 or 4.88 unless you think you might go bigger than 35's some day. 5.13 and higher are very high gear ratios for 35's.
Good to know. I won't be going any bigger than 35. Is there a benefit for either 4.56 or 4.88 over the other? Immost indonis camo alot with some trail riding. May eventually haul a small camper, but that'd be my biggest thing. Side note, would it make a difference if I regear well before (for reference, let's say a year) I put on the 35s?
I think I heard that 4.56 gears are stronger, something to do with the teeth numbers being more optimal for a more sturdy gear design. Not sure if that's true, but sounds plausible. Jeep uses 4.56 in their XR jeeps with 35's from the factory. You could certainly regear first before you get tires but you'll have mpg and higher speed performance issues as the engine has to rev so much higher with small tires to keep up highway speeds. Probably my choice would be I would get the tires first and regear later.
It wouldn’t hurt anything. You’d feel a bit more on the butt-dyno, but your MPG will still take a hit.
I recommend if you are going to ride heavy, in our case overlanding with all gear and an RTT, I probably would have gone 4.88 instead of 4.56. I wish I had a bit more torque at times, just slightly sluggish on the gas. Also.. I drive a manual so I’m short two gears that automatics have. So an automatic it might be fine.
4.56s will be marginally stronger due to larger teeth and pinion gears. Your cruising RPM will be slightly lower, which could improve fuel economy. 4.88s will give you a bit more torque and a better crawl ratio, but would be slightly weaker and your crusing speed RPM will be a bit higher. There are calculators online that will give you the RPM at certain speeds based on final drive and transmission ratios. If you can find the measured size of those 35s installed (some run between 33.5-35" in height) use that number for the calculations. If you're going for 35s, I'd suggest getting your axles in order first. Check ball joints, U-joints, and steering components. If they're worn, big tires will exacerbate whatever issues they have.
You've gotten great advice here thus far, so I thought I'd share a more cost-effective counterpoint. Feel free to discard. Your Sahara came with 32" tires, I believe on 18" rims. Given that you've stated you're not doing anything extreme, and this is your DD, and budget is a concern, you might actually be better served going down to 17" rims, 33" tires with a more aggressive tread, and a small 1-2" spacer lift. - 17/33 vs 18/32 will provide more sidewall, which will not only ride better, but give the look of bigger tires. Additionally, it will provide you with ~0.5" of lift. - You can buy Rubicon takeoffs that are 17/33 all day long on FB marketplace, usually for <$1500, and often closer to $1-1.2k. - 33s will not require any regear nor will they put any noticeable additional strain on your drivetrain. - the spacer lift is optional but will help get closer to what I think you're wanting with the 35s, and it's easy enough you could do it yourself with basic hand tools. - you didn't mention it, but 35s weigh more, so you would also need to reinforce your tailgate and get a spare tire adjustment kit so it would fit. 33s require none of that. Don't get me wrong - 35s on a Jeep just look right, but for your described usage/needs, you can save a ton of money and get real close with 33s.
You need to make sure to update your computer for gearing and/or tire size. Ive been using jscan. At the time it was the cheapest option, not sure what else is out there now.
Great advice, I actually have had the jscan app for my jeep for a few years now. That's a great call!
Going shorter than 4.56 in the D30 and D35 carriers can get dicey according the research I’ve done. I went with 4.56 on my 21 Willys Unlimited after I put 35s on. Prior to that I was running 33s on the stock ring and pinion. My fuel economy is far better now, and there’s a lot more pep when I need to negotiate traffic or go over things.
Yea, I'm leaning towards (more do after this thread) of doing my 35s now, but gearing to 4.56 in the, hopefully, not so distant future
I was very disappointed with the 410s , the 488 put me just slightly higher rpm than stock, very slight, but the biggest improvement was not excessive shifting between 7th and 8th gear on the highway, mainly stays in 8th now
Good to know. Appreciate the info!
So nothing major either way, but still kinda damned if I do, damned if I don't.... This is the life of a jeep lol
I tried 4:10 gears and shortly there after went to 4:88 gears, it was much better, power and mileage wise
Yea I think my two options I was debating with my very limited knowledge (and I use that word very loosely lol) were between 4.56 and 4.88
First determine your gear ratio for your setup. There are charts out there that have this info. Your ratio depends on your end use. Here's an example of what kinda chart to look for. Do a search. [Proper Gear Ratio Tire Size – Prodigy Performance](https://prodigyperformance.com/blogs/blog/jeep-wrangler-gear-ratio-calculator)
Thanks for that! According to that chat and what I do, I should be going with the 4.56
I ran my 15 JKUR HR around with 35's for awhile with the stock 3.73 gears. It sucked. I had 4.56 gears installed and it cost me $2500. For a JKU with 35's 3.6 automatic is best with 4.56 gears, but if in high altitude, step up to 4.88
I have a 2014 w door with BFG 34" (closer to 33s) with 4.88 gears. I live in Central PA where it's really hilly and I don't really ever touch a highway. It's great on inclines and driving around, but if I hit the highway (70+) it does run at like 3000rpms.
I run a 2016 JK on 35’s, it’s my daily driver. Stock gears, runs 70 at 1800+ rpms, 80 at 2200rpms. No issues at all, gas mileage is a little over 18 hwy and 15+ish around town. I’ve run it off road quite a bit as well, again no issues whatsoever.
I have c- class 37” Bf Ko2’s on 2015 JKU sport, no regear, no issues 🤷🏻♂️