Revolution Gear & Axle 07-18 Jeep Wrangler JK Dana 30 Front Ring & Pinion Master Install Kit

Most 2007-2018 Jeep Wrangler JK Sport and Sahara models came with a Dana 30 front axle, and most of them eventually get bigger tires and new gears. If you are regearing a JK to bring back power after a tire upgrade, or chasing a front-end whine on a high-mileage Jeep, the Revolution Gear and Axle 35-2050 is the Timken-bearing master install kit built for that axle. It covers the bearings, shims, seals and hardware for one Dana 30 front center section.

What the master install kit does in a JK Dana 30 front

The JK Dana 30 front is a reverse-rotation design with 27-spline axle shafts, which is why it needs reverse-cut gears rather than a standard Dana 30 set. The pinion rides on two tapered bearings preloaded by a crush sleeve, the carrier rides on two side bearings, and shims set pinion depth and backlash. Per Revolution, 35-2050 includes Timken pinion bearings and carrier bearings, pinion seal, crush sleeve, pinion shims, carrier shims, ring gear bolts, cover gasket or silicone and axle seals. Having the inner axle seals in the box matters on a JK front, because the shafts have to come out to pull the carrier anyway.

Symptoms that call for this kit

• A whine from the front that comes and goes with throttle, often worse in 4WD or on decel
• Gear oil at the inner knuckle or the tube ends, a sign the inner axle seals are leaking
• Play at the front pinion flange or a pinion seal that keeps weeping
• Sluggish acceleration and constant downshifting after 35 inch or larger tires, the classic reason to regear
• Metal glitter in the front diff oil at a fluid change

How to confirm before ordering

Check the axle tag and the build sheet before anything else, because a Rubicon has a Dana 44 front that needs a different kit. Drain the oil and look for metal, then rock the pinion flange to check for play. If you are regearing, decide your ratio and whether the carrier must change first. Our JK regear kit buyers guide lays out the front and rear axles by trim, and the Dana 30 front axle problems guide covers noise and seal checks.

Fitment

This kit is listed for the 2007-2018 Jeep Wrangler JK with the Dana 30 front axle. It does not fit the JK Rubicon Dana 44 front, the 2018-up JL Dana 30 (M186), the TJ Dana 30, or the rear axle. Some used JKs have had axles swapped, so read the tag or send us your year and VIN. Revolution also sells this kit with Koyo bearings, which we carry as the K35-2050 Koyo JK Dana 30 kit. More JK and axle parts are in our rebuild kits category.

Install notes

Revolution's setup chart lists the D30JK at a 0.065 inch starting pinion shim, 12-15 in-lb pinion bearing preload, 0.006-0.010 inch backlash, 55 or 75 ft-lb on the ring gear bolts depending on bolt size, and 60 ft-lb on the bearing caps. Treat the shim as a starting point and read the contact pattern, as shown in our backlash and pinion depth setup guide. Use only reverse-rotation JK gears, such as the Revolution JK/JL Dana 30 reverse 4.88 set, and confirm your carrier matches the new ratio; the Yukon JK Dana 30 replacement carrier is sold for 3.73 and up ratios. Drive the new inner axle seals in square, and a Dana 30/44/60 inner axle seal installer keeps them from cocking in the tube. A housing spreader helps with a tight carrier. Fill with 75W-90 GL-5 and follow the new gear break-in procedure.

Does this kit fit a JK Rubicon?

No. The JK Rubicon has a Dana 44 front axle. This 35-2050 kit is for the Dana 30 front used on most Sport and Sahara models. Revolution sells K35-2051 and 35-2051 for the Rubicon front.

Are inner axle seals included?

Yes. Revolution lists axle seals as included in 35-2050, along with Timken pinion and carrier bearings, pinion seal, crush sleeve, pinion and carrier shims, ring gear bolts and gasket or silicone.

Will it fit a JL Wrangler?

No. The 2018-up JL uses a different Dana 30 (M186) with its own setup specs and kit. This kit is for the 2007-2018 JK only.

What gears do I need with it?

Reverse-rotation Dana 30 JK gears. A standard-rotation Dana 30 set will not work in the JK front. Match the front ratio to the rear and check whether your carrier needs to change for the new ratio.

What fluid does the JK front axle take after a regear?

75W-90 GL-5 gear oil. Change it after the gear break-in miles, since new gears shed fine metal while they seat.