Rear Differential

Includes : 

• 6 x Differential Housing Lock Plate. (90133228501) 
• 12 x Hexagon-head bolt (92833227606)

Fits:
Porsche 911 1965-89
Porsche 914 1970-76
Porsche 924 1976-85

Click 'Zoom in' for large parts diagram.
Diagram ref no 8.

Differential rebuild kit for Porsche 911 1987–1989 G50 gearbox cars by OE Match, suitable for selected 911 3.2 G50 and 3.3 Turbo (930) models.

What This Product Does This kit provides the core components typically required to overhaul the rear differential assembly on G50-equipped Porsche 911 models, helping restore correct internal clearances and consistent operation of the unit.

Kit includes: 

1 x Differential outer bearing, (Ref: 99905906400) 
1 x Taper roller bearing. (Ref: 99905902702) 
6 x Differential Housing Lock Plate. (Ref: 90133228501) 
12 x Hexagon-head bolt (Ref: 92833227606)

Functions

• Supports refurbishment of worn differential internals
• Helps re-establish correct bearing support and gear contact
• Assists in reducing internal play and backlash when set up correctly
• Provides parts needed for a planned diff rebuild alongside other drivetrain work

Symptoms of Fault

• Whining or howling noises from the rear at cruise or on overrun
• Clunks when taking up drive or during gear changes
• Noticeable backlash or “thud” in the driveline
• Oil leaks from differential side seals or input area
• Vibration or roughness that changes with road speed
• Reduced or inconsistent traction on cars with limited-slip units

Why Replacement Matters

Over time, bearings, shims and internal hardware in the rear differential wear, especially on older Porsche 911 models that see mixed road use and age-related degradation. Refreshing these parts during a rebuild helps stabilise gear alignment, supports smooth torque transfer and can prevent accelerated wear of crownwheel, pinion and bearings. For G50 cars in particular, maintaining a healthy differential complements the robust gearbox design and contributes to a more predictable, refined drivetrain.

Fits

• Porsche 911 & 912 (1965–1989) – selected models with G50 gearbox
• Porsche 911 1987–1989 3.2L G50
• Porsche 911 1978–1989 3.3L Turbo (930) – applicable versions with G50 transmission

Fits:
Porsche 911 - 1972 to 1986 with 915 Gearbox
Porsche 968 - 1992 to 1995 
For cars with Porsche LSD fitted - Option Code M220 (Locking differential 40 %)

Upgrade the standard Porsche LSD to these Track Day / Race inspired components for improved, performance traction.

Kit Includes:
Friction Plate Upgrade Set
Multi Variation Ramp Set

RacingDiffs Performance LSD clutch plates fit OEM Porsche (ZF) LSD unit without any modifications:

The clutch discs are perforated for better cooling and great viscosity to resist the oil build-up in the holes between dog ear plates as it is well known that drilled brake discs improve cooling over solid discs. It is the same with the LSD clutch discs.

The highest quality thermally processed tool steel is used which differentiates our products from any others on the market.

During the final steps of production the clutch plates are coated with special Molybdenum-Ceramic compound which optimizes the best ratio of friction coefficient and durability. This drastically reduces material wear and warping under extreme conditions providing our clutch plates the best possible longevity.

We mastered knowledge in the field of friction materials and coatings, which is the cornerstone of the quality of our products.

All of our clutch plates are thoroughly tested and are currently being used in various racing cars throughout Europe and USA including track, hill climb and rally.

Please Note:
Friction plate upgrade kit should only be fitted by someone with the relevant knowledge and experience.