4x4 Offroad

Offroad enthusiasts entrust their safety to Colorado Axle and Gear owner Albert Lovi when they bring their vehicles to him for upgrades and repairs, and he takes that trust seriously. That’s why Lovi uses only the best parts on the market, and customizes his services depending on the situation, to make sure every client gets exactly what they need.

Colorado Axle and Gear does gear ratio changes and has complete axle assemblies for customers who put extra stress on their vehicles, and carries parts by ARB, Detroit, Ox Lockers, Revolution, AAM and Eaton / Detroit. Denver

Email: Al@axlengear.com
Hours: 8AM – 5PM Mon – Fri
Address: 2611 W. 64th Ave # A
Denver, CO. 80221
Phone: (303)286-0338
(800)893-0338

4X4 Off-Road Axle and Differential Upgrades in Denver

Colorado’s terrain demands a capable 4×4 drivetrain. Whether you’re crawling trails in Ouray, rock hopping in Moab, or running the high-altitude forest roads of the San Juans, your axles and differentials are what keeps you moving forward when the going gets tough. Colorado Axle and Gear has been building and repairing off-road drivetrains in Denver for over 30 years — and our team runs the trails themselves.

Off-Road Axle Upgrades

Factory axles are engineered for street use. When you add larger tires, increased suspension articulation, and serious off-road loads, the weak links reveal themselves. We replace, upgrade, and repair axle shafts on all popular 4×4 platforms. For vehicles running 37-inch or larger tires, we can source and install heavy-duty chromoly axle shafts from manufacturers like Superior Axle, Strange Engineering, and Yukon Gear that dramatically outlast factory parts under hard use.

Regearing for Bigger Tires

The single most impactful modification you can make after a tire size increase is a regear. Factory gear ratios are calibrated for stock tire diameters. When you go bigger — say, from stock 265/70R17s to 35-inch or 37-inch tires — the rotational mass increases and your effective gear ratio becomes taller (numerically lower), resulting in sluggish acceleration, poor fuel economy, and excessive drivetrain wear. We calculate the optimal ratio for your specific tires and transmission and install new ring and pinion gears at both axles. Most Jeep JL and Tacoma owners with 37-inch tires choose a 4.88 or 5.13 ratio.

Locking Differentials

A locker is the most effective traction upgrade you can make to your 4×4. When one wheel lifts off the ground, an open differential sends all power to that wheel — the one with no traction. A locker eliminates that problem by mechanically locking both wheels to spin together. We install and service:

  • ARB Air Lockers — Selectable air-actuated lockers for controlled on-demand traction. Excellent for vehicles used both on- and off-road.
  • Detroit Lockers — Automatic locking differentials with proven off-road performance and aggressive engagement.
  • Eaton E-Lockers — Electric selectable lockers popular on Tacomas and 4Runners.
  • Spicer Trac-Lok — Heavy-duty limited-slip units for improved traction without full locker engagement.

Platforms We Work On

Jeep Wrangler JL, JK, TJ, and older CJs; Toyota Tacoma (all generations); Toyota 4Runner (3rd, 4th, 5th gen); Toyota Land Cruiser; Ford Bronco (2021+); Ram 2500 and 3500; Ford F-250 and F-350; Chevy/GMC Silverado and Sierra HD; and many more. If you’re unsure whether we handle your platform, call us — we almost certainly do.

Frequently Asked Questions — 4X4 Off Road

Should I regear when I go to 35-inch tires?

We recommend regearing when you move to 35-inch or larger tires. For most Jeeps and trucks, 35s call for a 4.56 ratio and 37s call for 4.88 or 5.13. Even at 33 inches on some gearing-sensitive platforms like the Jeep JL, a regear can noticeably improve drivability.

How long does a front and rear regear take?

A front and rear regear typically takes 1 to 2 business days, depending on parts availability and whether any additional work like locker installation is done at the same time. We will give you an accurate timeline when you bring the vehicle in.

Do I need to break in new gears after a regear?

Yes. After a regear, we recommend a break-in period of approximately 500 miles that includes varied driving speeds while avoiding sustained highway speeds or heavy towing. After the break-in, we recommend a differential fluid change. We will walk you through the specific break-in procedure for your setup.