What gear ratio should I go with?

[Anthony TJ]

I have a 2002 jeep wrangler TJ with 35. Manuel transmission with 6 cylinder. Planning to buy front and rear axle dana 40. Living in orange county and planning to visit big bear and surrounding areas. Some rock crawling. My question is what gearing to go with and lockers? Planning to buy from east coast gearing. Any advise on where to buy new axles and are dana 40 a hood choice?

 

[Jerry Bransford]

What to regear to Anthony depends on your tire size. What size tires are you running? We are in the same area and I wheel BB and the surrounding areas.

This is who I recommend in your area to regear... Martin at Mobile Gears. He came highly recommended by Revolution Gear and they were right to recommend him.

Axle-wise, a Dana 44 in the rear is great. The factory Dana 30 is fine for up to 35" tires, it may just need stronger shafts if you plan to install a front locker. For our wheeling conditions I'd go with a rear locker first.

 

[Chris]

Manuel transmissions are the best

 

[Jerry Bransford]

Manuel transmissions are the best

Nah, Jose transmissions left Manuel in the dust years go.

 

[Anthony TJ]

What to regear to Anthony depends on your tire size. What size tires are you running? We are in the same area and I wheel BB and the surrounding areas.

This is who I recommend in your area to regear... Martin at Mobile Gears. He came highly recommended by Revolution Gear and they were right to recommend him.

Axle-wise, a Dana 44 in the rear is great. The factory Dana 30 is fine for up to 35" tires, it may just need stronger shafts if you plan to install a front locker. For our wheeling conditions I'd go with a rear locker first.

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Sorry I am running 35 inch tires. What gearing is the best in our area and my front diff will be ok?

 

[Jerry Bransford]

Sorry I am running 35 inch tires. What gearing is the best in our area and my front diff will be ok?

4.88 is a great ratio for 35's, you might even consider 5.13 but I ran 4.88 with your combination (4.0/5-speed manual trans and 35" tires) all over SoCal for years and it worked extremely well.

Don't worry about your Dana 30 which only sees roughly 50% of the load the rear axle can see on a regular basis. Without a front locker it's good as-is. If you add a front locker I'd replace the axle shafts with Revolution Gear's 27 spline 4340 inner/outer axle shaft kit which is an easy upgrade. I ran my previous TJ through some very tough trails including Sledgehammer in JV with that Dana 30 with the 4340 27 spline shafts and it held up without problem.

 

[Anthony TJ]

4.88 is a great ratio for 35's, you might even consider 5.13 but I ran 4.88 with your combination (4.0/5-speed manual trans and 35" tires) all over SoCal for years and it worked extremely well.

Don't worry about your Dana 30 which only sees roughly 50% of the load the rear axle can see on a regular basis. Without a front locker it's good as-is. If you add a front locker I'd replace the axle shafts with Revolution Gear's 27 spline 4340 inner/outer axle shaft kit which is an easy upgrade. I ran my previous TJ through some very tough trails including Sledgehammer in JV with that Dana 30 with the 4340 27 spline shafts and it held up without problem.

I am thinking 5.13 gearing. Do you think I will be ok?

 

[L J]

Sorry I am running 35 inch tires. What gearing is the best in our area and my front diff will be ok?

4.88 if you drive fast on the freeway or 5.13 if you keep it at 65ish mph, selectable lockers front and rear if you have the budget, selectable rear locker and Powertrax no-slip front locker if you don't, 4130 chromoly shafts front and rear if you have the budget, 4130 chromoly front shafts if you don't

 

[L J]

I am thinking 5.13 gearing. Do you think I will be ok?

Yes. I have a 35s, 5.13s and a shorter overdrive gear.

 

[Jerry Bransford]

I am thinking 5.13 gearing. Do you think I will be ok?

I'd choose 5.13 over 4.88, especially due to the climbs we have to make up to Big Bear and to get up & over the mountains to the desert. It'd be a great all-around ratio.

 

[Anthony TJ]

Wow you guys that was great information. Thank you so much.

 

[Brandough]

What to regear to Anthony depends on your tire size. What size tires are you running? We are in the same area and I wheel BB and the surrounding areas.

This is who I recommend in your area to regear... Martin at Mobile Gears. He came highly recommended by Revolution Gear and they were right to recommend him.

Axle-wise, a Dana 44 in the rear is great. The factory Dana 30 is fine for up to 35" tires, it may just need stronger shafts if you plan to install a front locker. For our wheeling conditions I'd go with a rear locker first.

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Hey Jerry I’m going to get my regear and lockers done through them he recommended going to 30 spline in the Dana 30 is that better than the 27? I will be upgrading my Dana 30 shafts to chromoly and it doesn’t affect price.

 

[Jerry Bransford]

Hey Jerry I’m going to get my regear and lockers done through them he recommended going to 30 spline in the Dana 30 is that better than the 27? I will be upgrading my Dana 30 shafts to chromoly and it doesn’t affect price.

For up to 35's 27 spline 4340 shafts are absolutely fine in the front Dana 30. It's difficult to go with 30 spline inner/outer shafts on a Dana 30 since you have to convert to manual hubs to run 30 spline outer shafts.

My previous TJ's Dana 30 did perfectly well with 27 spline 4340 shafts with 35's, lockers, etc. even on Sledgehammer in Johnson Valley (a VERY tough rock crawling trail) . Keep in mind the front axle seldom sees more than about 50% of the load the rear axle sees.

 

[Anthony TJ]

I did call Martin. He did recomend I go dana 44 in front.

 

[tworley]

I did call Martin. He did recomend I go dana 44 in front.

Stick with your 30 and 5.13 choice. You'll be just fine

 

[Anthony TJ]

5.13 will be ok freeway driving?

 

[tworley]

No issues whatsoever

 

[Jerry Bransford]

5.13 will be ok freeway driving?

Absolutely. And as much as I respect Martin a Dana 30 is absolutely fine with 35's. If you install a front locker just replace the factory 27 spline carbon steel axle shafts with 27 spline 4340 axle shafts. As I did on my previous TJ.

 

[Anthony TJ]

Ok thank you

 

[Andersen24]

OK instead of reinventing the wheel - I figured I’d add onto this for my question. I just want to confirm. I have a 97 sport 4.0 liter automatic running 33x12.50x15’s. Front is a Dana 30 and rear is a Dana 35. I am looking at switching both of them to 4.56’s. Is that correct? Going over the Cuesta Grade in San Luis as is.......it EVENTUALLY gets there .......oh and I assume I will need new carriers as well.