drivetrain

Differential Cover Gasket

for 2012 Jeep Wrangler 3.6L V6 · 4WD

Difficulty

Easy

Time

48 min

Tools

Steps

Replace the differential cover gasket on front or rear axle to repair leaks, including draining and refilling with fresh gear oil.

Warnings

⚠Gear oil will be hot if vehicle was recently driven. Allow differential to cool for at least 1 hour before starting work.

⚠Gear oil has a strong sulfur smell and can stain. Work in a well-ventilated area and protect the ground surface.

ℹ️This procedure applies to both front and rear differentials. Front differential requires 1.5 quarts, rear requires 2.0 quarts of fluid.

Tools required

3/8" drive ratchet and socket setEssential

Torque wrench (10-50 Nm range)Essential

Fluid drain pan (3+ quart capacity)Essential

Gasket scraper or plastic scraperEssential

Brake cleaner or parts cleanerEssential

Clean lint-free ragsEssential

RTV silicone sealant (Mopar or equivalent)Essential

Fluid pump or turkey baster

Jack and jack standsEssential

Wheel chocksEssential

Parts

Differential cover gasket × 1 — Use OEM Mopar gasket for front or rear differential

Fluids

Mopar 75W-140 Synthetic Gear Lubricant — 2 qt

Preparation

Park vehicle on level ground and engage parking brake
Place wheel chocks behind wheels that will remain on ground
Raise and support vehicle on jack stands at frame points
Identify which differential needs service (front or rear)
Ensure differential has cooled to safe working temperature
Clean exterior of differential cover with brake cleaner to prevent contamination

Procedure

1
Drain differential fluid
Position drain pan beneath differential cover. Loosen all differential cover bolts gradually in a cross pattern, leaving top two bolts partially threaded. Carefully pry the bottom edge of cover away from housing to allow fluid to drain into pan. Once fluid stops flowing, remove remaining bolts and cover.
2
Remove old gasket material
Remove and discard old gasket from differential cover. Use gasket scraper to remove all gasket material from both the cover mating surface and differential housing mating surface. Take care not to gouge or scratch the metal surfaces. Clean both surfaces thoroughly with brake cleaner and lint-free rags until completely clean and dry.
3
Inspect differential components
With cover removed, visually inspect differential gears and bearings for unusual wear, metal shavings, or damage. Check for broken teeth or scoring. If metal debris is present in old fluid or housing, further diagnosis is required before reassembly.
ℹ️Slight residual oil film is normal. Large metal particles, chunks, or excessive glitter in old fluid indicates internal wear requiring professional inspection.
4
Install new gasket with RTV
Apply thin continuous bead of RTV silicone sealant to the differential housing mating surface, circling all bolt holes. Position new gasket onto housing, ensuring all bolt holes align. Apply another thin bead of RTV to outer surface of gasket. Allow RTV to become tacky (3-5 minutes) before installing cover.
ℹ️Use only a thin bead of RTV. Excess sealant can squeeze into differential and contaminate bearings.
5
Install differential cover
Carefully position cover onto differential housing, aligning all bolt holes. Install all differential cover bolts hand-tight. Torque bolts in a cross pattern (star pattern) to specification in three stages: first to 13 Nm (10 lb-ft), then to 26 Nm (19 lb-ft), and finally to full specification.
Torque spec
Differential Cover Bolts39 Nm (29 lb-ft)
6
Allow RTV to cure
Allow RTV sealant to cure for minimum 15 minutes before filling with fluid. For best results, wait 30 minutes. Check torque on all cover bolts and re-torque if necessary after cure time.
7
Refill differential with gear oil
Locate fill plug on differential housing (typically on passenger side or top). Remove fill plug. Using fluid pump or squeeze bottle, add Mopar 75W-140 Synthetic Gear Lubricant until fluid level reaches bottom of fill hole and begins to seep out. For rear differential use 2.0 quarts, for front differential use 1.5 quarts. Install and tighten fill plug.
ℹ️Do not overfill. Proper level is reached when fluid just begins to drip from fill hole with vehicle level.
8
Check for leaks
Wipe down entire differential cover area with clean rag. Inspect all edges of cover for any fluid seepage. If leak is visible, differential must be drained and cover removed to correct seal installation.

Reassembly

Lower vehicle from jack stands
Remove wheel chocks
Dispose of used gear oil properly at recycling facility

Verification

Start engine and let idle for 30 seconds, then shift through all gears (transmission in Park/Neutral for final check)
Drive vehicle forward and reverse for 10 feet to circulate gear oil
Re-inspect differential cover for any signs of leakage around gasket
After first 50 miles of driving, re-check fluid level at fill plug and inspect cover area for leaks
Monitor for leaks over next 500 miles during regular vehicle walk-around checks