drivetrain

Differential Fluid Change - Rear

for 2002 Dodge Viper 8.0L V10 · RWD

Difficulty

Easy

Time

42 min

Tools

Steps

✓Fact-checked. Built from OLP's spec database, then independently fact-checked line by line with every correction applied. Master-tech sign-off by Chris Hackleman is queued. Cross-check torque values against the factory manual, and stop if anything looks unsafe. How our data is made.

Drain and refill the rear differential with fresh 75W-90 GL-5 gear oil and limited-slip additive to maintain proper lubrication and extend differential life.

Warnings

⚠Perform this service with the vehicle on level ground to ensure accurate fill level.

⚠Gear oil may be hot if the vehicle was recently driven. Allow at least 30 minutes cool-down time.

ℹ️The Viper rear differential uses a limited-slip unit requiring friction modifier additive. Do not omit this additive or chatter and premature wear will occur.

ℹ️Used gear oil may contain metal particles. Inspect drained fluid for excessive debris which may indicate internal wear.

Tools required

3/8" drive ratchetEssential

3/8" drive socket set (metric)Essential

Torque wrench (10-50 Nm range)Essential

Drain pan (5-quart capacity minimum)Essential

Fluid pump or funnel with hoseEssential

Wire brush

Shop ragsEssential

Safety glassesEssential

Nitrile glovesEssential

Jack and jack stands (if additional clearance needed)

Gasket scraper (plastic or brass)

As an Amazon Associate and Autel/ANCEL partner, OLP earns from qualifying purchases — how we link. This never changes the specs we publish.

Parts

Differential cover gasket × 1 — Use OEM specification or RTV silicone gasket maker
Limited-slip additive × 1 — Mopar limited-slip additive or equivalent (4 oz)

As an Amazon Associate and Autel/ANCEL partner, OLP earns from qualifying purchases — how we link. This never changes the specs we publish.

Fluids

75W-90 GL-5 with limited-slip additive — 3.5 qt

Preparation

Park vehicle on level ground and engage parking brake.
Allow differential to cool if vehicle was recently driven (minimum 30 minutes).
If additional clearance is needed, raise rear of vehicle with jack and support securely on jack stands rated for vehicle weight.
Locate the rear differential cover at the rear of the differential housing, facing rearward.
Clean the exterior of the differential cover and surrounding area to prevent contamination during service.

Procedure

1
Position drain pan and loosen cover bolts
Position the drain pan directly beneath the differential cover. Using the 3/8" ratchet and appropriate socket, loosen all differential cover bolts in a crisscross pattern, but do not remove them completely yet. This allows pressure to equalize before full removal.
2
Remove cover bolts and drain fluid
Remove all cover bolts except the top two, working from bottom to top. Carefully pry the bottom edge of the cover away from the housing using a gasket scraper or flat tool to break the seal and allow fluid to drain into the pan. Once fluid flow slows, remove the remaining two top bolts and carefully remove the cover. Allow all fluid to drain completely.
3
Inspect differential internals and drained fluid
With the cover removed, visually inspect the ring gear, pinion gear, and side gears for obvious damage, scoring, or excessive wear. Inspect the drained fluid for metal particles, shavings, or excessive debris. Fine metallic particles are normal, but large chunks or excessive material indicate potential internal damage requiring further diagnosis.
4
Clean cover and gasket surfaces
Remove all old gasket material from both the differential cover and the housing mating surface using a gasket scraper. Use a wire brush if necessary to remove stubborn residue. Wipe both surfaces clean with shop rags. Ensure no debris falls into the differential housing during cleaning. The mating surfaces must be completely clean and dry for proper gasket sealing.
5
Install new gasket and position cover
Install the new differential cover gasket onto the cover, or apply a continuous 3mm bead of RTV silicone gasket maker to the cover flange if using RTV instead of a preformed gasket. Position the cover onto the differential housing, ensuring the gasket seats properly and all bolt holes align. Start all cover bolts by hand to ensure proper thread engagement.
6
Torque cover bolts
Using the torque wrench, tighten the differential cover bolts in a crisscross pattern to the specified torque. Tighten opposing bolts across the bolt circle in a crisscross (star) pattern to ensure even gasket compression and prevent leaks. Make multiple passes, gradually increasing torque to final specification.
Torque spec
Differential Cover Bolts35 Nm (26 lb-ft)
7
Refill differential with gear oil
Using a fluid pump or funnel with hose inserted into the fill hole (upper passenger side of differential housing), add approximately 2.75 quarts of 75W-90 GL-5 gear oil. Add the limited-slip additive (typically 4 oz) according to the additive manufacturer's instructions. Continue adding gear oil slowly until fluid begins to seep from the fill hole. The differential is properly filled when fluid reaches the bottom of the fill hole threads.
8
Install fill plug and verify seal
Clean the fill plug threads and install the fill plug, tightening securely. Wipe away any excess fluid from the differential housing exterior. Visually inspect the cover gasket seal for any signs of leakage. If RTV was used, allow 1 hour cure time before driving.

Reassembly

If vehicle was raised, lower from jack stands and remove jack.
Dispose of used gear oil according to local environmental regulations.
If RTV silicone was used instead of a preformed gasket, allow minimum 1 hour cure time before operating vehicle.

Verification

Start the vehicle and allow it to idle for 2-3 minutes, then shift through all gears.
Drive the vehicle in a figure-eight pattern at low speed to distribute the new fluid and additive throughout the limited-slip unit.
After a short test drive (5-10 minutes), re-inspect the differential cover gasket area for any signs of leakage.
Listen for any unusual noise or chatter from the rear differential during turns, which may indicate insufficient limited-slip additive.
After 50-100 miles of driving, perform a final inspection of the cover gasket for leaks and retorque cover bolts if necessary.