Yukon Gear Master Overhaul Kit For Toyota 7.5in IFS Diff For T100 / Tacoma / and Tundra

A first-generation Tacoma or early Tundra 4x4 that howls from the front end only when four-wheel drive is engaged, or drips gear oil from the front pinion or a CV axle seal, is usually telling you the front differential needs bearings and seals. This Yukon Gear and Axle YK T7.5-REV-FULL master overhaul kit is built for Toyota's 7.5-inch independent front differential, the reverse-cut unit Toyota bolted into the front of its IFS trucks. It gives you every bearing, race, seal and shim needed to rebuild the center section in one box.

What the master overhaul kit does in a Toyota 7.5 IFS front

The late-model 7.5-inch IFS front is a high-pinion, reverse-cut design. Because the front diff sits ahead of the engine and turns the opposite way from a rear axle, Toyota cut the gears so the stronger drive side of the teeth carries the load in forward. The pinion rides on two tapered bearings held under preload by a crush sleeve, and the carrier spins on two side bearings set by shims. When any of those four bearings wears, the pinion walks under load, the gear pattern shifts and the whine starts. The kit replaces all four bearing and race sets with Timken parts and supplies the pinion seal, axle seals, a complete shim kit, ring gear bolts, pinion nut, crush sleeve, oil baffles and slingers, thread locker, marking compound with a brush and silicone for the cover.

Symptoms that point to this rebuild

• Whine or hum from the front that appears or gets louder only with 4WD engaged
• Growl on decel in 4WD High that changes with throttle rather than steering
• Gear oil seeping past the pinion seal onto the front driveshaft flange
• Wet seal area where the CV axles enter the differential
• Bearing flakes or glitter on the drain plug magnet
• Clunk when 4WD engages after the pinion bearings loosen

How to confirm it before you buy

Drive in 2WD and then 4WD at the speed where the noise shows up. If the sound disappears in 2WD, the front diff is the prime suspect, because the front gears only carry load with the transfer case engaged. A noise that changes when you steer left or right is more likely a hub bearing or CV joint. With the front driveshaft unbolted, grab the pinion flange and rock it to feel for play, then drain the oil and look at the plug. Before teardown, set a dial indicator on a ring gear tooth to record backlash so you have a baseline to rebuild to.

Fitment

Yukon sells this kit for the Toyota 7.5-inch IFS front differential in the T100, Tacoma and Tundra, and lists it as fitting the reverse-rotation 7.5-inch front. Gear references place that reverse-cut unit in the 1995-2003 Tacoma, 2000-2004 Tundra and 1996-2002 4Runner. The same references list the T100 front as the earlier low-pinion 7.5-inch design, so T100 owners should confirm which unit they have before ordering. Later Tacomas moved to an 8-inch clamshell front that this kit does not fit. Match your ring gear and pinion to the part, or send us your year and VIN and we will check it. The USA Standard version of this kit covers the same axle with a different bearing brand, and more kits are on the rebuild kits page.

Install notes

• Mark the old gear pattern and measure backlash and pinion preload before you take anything apart.
• The stub axle bearings that live inside the carrier bearing journal are not in this kit. Inspect them while the diff is open and order them separately if they are rough.
• Pull the side bearings with a carrier bearing puller set so the original shims come off undamaged and can be measured.
• Install a new crush sleeve and tighten the pinion nut in small steps while checking rotating torque. An over-crushed sleeve has to be replaced, not backed off.
• Paint the ring gear with the included compound and adjust shims until the pattern centers on both drive and coast sides.
• Refill with the hypoid gear oil grade and capacity listed in your owner's manual.

If you are regearing for bigger tires at the same time, this kit pairs with a reverse-rotation 4.88 gear set or a Revolution 4.88 ring and pinion; match the rear axle ratio exactly.

Does this kit fit a 2005 or newer Tacoma?

No. Toyota moved the 2005-and-later Tacoma to an 8-inch clamshell front differential. This kit is for the 7.5-inch reverse-cut IFS front used in the 1995-2003 Tacoma and 2000-2004 Tundra.

Will it fit my T100?

Yukon lists the T100, but gear references show the T100 front as the earlier low-pinion 7.5-inch unit rather than the reverse-cut version. Send us your year and VIN or check your pinion before ordering.

What bearings come in the kit?

Timken carrier bearings and races and Timken pinion bearings and races, along with the pinion seal, axle seals, full shim kit, ring gear bolts, pinion nut, crush sleeve, baffles, slingers, thread locker, marking compound and silicone.

Are the stub axle bearings included?

No. The stub axle bearings inside the carrier bearing journal are not part of this kit and are sold separately.

Can I reuse my ring and pinion with this kit?

Yes, if the teeth are not pitted or chipped and the pattern was good. Reuse the original pinion depth shim as a starting point and confirm the pattern after assembly.