Revolution Gear & Axle 2018+ Jeep Wrangler JL Non-Rubicon Dana 44 Rear 4.88 Ratio Gear Package
A 2018-up Wrangler JL Sport or Sahara that came with the optional Dana 44 rear axle is a common starting point for a big-tire build, and once it is wearing 37-inch tires the factory ratio cannot keep up. The Jeep crawls away from lights, the transmission hunts for a gear on every hill and towing feels like work. This Revolution Gear & Axle package, part number REV-JL-220/186-488, re-gears both axles to 4.88 in one box: a ring and pinion for the Dana 44 220 mm rear, a matching set for the Dana 30 186 mm front, and a master install kit for each axle with Timken bearings.
Non-Rubicon JL models do not use the Rubicon's Dana 44 front. The front axle is the Dana 30 186 mm, which Revolution lists with a 26-spline pinion, while the optional heavy rear is the Dana 44 220 mm with a 28-spline pinion. The ring and pinion in each axle is the last gear reduction before the wheels, so when tire diameter grows the effective gearing gets taller and the engine falls below its useful RPM range. A 4.88 ratio is one of the steepest common choices for this axle pair and is usually picked for 37-inch tires, heavy armor, or a Jeep that tows or crawls more than it cruises. Revolution builds these gear sets from 8620 steel in Korea and pairs them with complete bearing kits so both axles are set up from fresh parts.
First confirm which axles you have. The 4.88 gears here only fit a JL with the Dana 44 220 mm rear; a JL with the smaller Dana 35 200 mm rear needs the Dana 35 rear package instead. Read the axle tag or ring gear tooth count (ratio is ring teeth divided by pinion teeth). Then decide on the ratio. If you are on 35s and mostly drive pavement, the same package in 4.56 keeps highway RPM lower. Many differentials also have a carrier break, so check with your installer that your current front and rear carriers accept a 4.88 ring gear before the Jeep is torn down.
Listed for 2018-up Jeep Wrangler JL non-Rubicon models with the Dana 30 186 mm front and Dana 44 220 mm rear. It does not fit the Rubicon or the Gladiator, which use a Dana 44 front; those owners want the JL Rubicon and JT package. Because the front and rear must turn at the same ratio, both axles are re-geared together. Send us your year and VIN if you are unsure what is under your Jeep, and see the rest of our axle parts in hard parts.
Revolution's setup chart gives a starting pinion depth of 0.045 in for the Dana 44 JL M220 and 0.050 in for the Dana 30 JL M186. With Revolution's master kit, the M220 pinion bearing preload is 22-35 in-lb, backlash is .006-.010 in for 5-cut gears, ring gear bolts are 135 ft-lb and bearing caps are 70 ft-lb. The M186 front runs 15-20 in-lb pinion preload, .006-.010 in backlash and 70 ft-lb on both ring gear bolts and caps. Check every setup with marking compound before closing the cover. If you only need to rebuild the rear bearings later, the Dana 44 rear master install kit is sold on its own.
Fill with a name-brand petroleum GL5 gear oil, follow Revolution's break-in cycles, and change the oil at 500 miles. Then program the new tire size and axle ratio so the speedometer, shift points and stability systems read correctly.
| Brand | Revolution Gear & Axle |
| Part number | REV-JL-220/186-488 |
| Fits | Revolution Gear & Axle 2018+ Jeep Wrangler JL Non-Rubicon Dana 44 Rear 4.88 Ratio Gear Package |
| Vehicle fitment | Jeep Wrangler Jl Non-Rubicon (2018) |
| Type | Differential Install Kits |
| Condition | New |
| Ships | Same business day (in stock), from the USA |
| Warranty | 1-year |
Doing this repair right usually means replacing these at the same time. Same transmission, ships together.
No. This package is for the Dana 44 220 mm rear. JL Sport and Sahara models with the Dana 35 200 mm rear need the Dana 35 version of the package. Check the axle tag or send us your VIN.
On 37-inch tires 4.88 is a common pick that brings engine speed back into the power band. On 35s with mostly highway use, 4.56 keeps cruising RPM lower. Use tire size and how you drive to choose.
A 4.88 ring and pinion for the Dana 44 220 mm rear, a 4.88 ring and pinion for the Dana 30 186 mm front, and a master install kit with Timken bearings for each axle.
No. On a four-wheel-drive Jeep the front and rear must share the same ratio or the transfer case and driveline will bind in 4WD. Both axles are geared together.
Break the gears in with short, easy drive cycles, change the gear oil at 500 miles, and reprogram tire size and axle ratio so the speedometer and transmission shift schedule are correct.
