top of page

Highly recommended for modified P-cars with above 700HP!


Speed Density Motorsports is proud to release another problem solving product. The 997.1 and 997.2 front differential assemblies are notorious for premature failure, even on 911’s that have yet to receive performance upgrades. You could source a replacement unit used for $2,000 to $3,000 or even a new one at $8,000 USD and above and yet you will still be faced the underlining problem and it will eventually fail.


Have you ever wondered why they fail? A quick search will give you many theories as to why they fail, “Wrong tire sizes”, “The seal for the front differential cover must have worn out and failed”, and “Lack of service”. First lets take a engineering look at the unit. The front differential for the 997.1 and 997.2 Turbo was manufactured by Getrag, just like the previous 996 unit. The changes made to the 997 are the final drive ratio 3.33 (vs 3.44, 996 model), electronically controlled clutch center differential , two separate oil chambers which included one for the clutch fluid and one for final drive. The new electronically controlled clutch center differential allows much more torque to be transferred to the front ring and pinion, front axles and then finally front wheels. The extra torque will eventually find the weakest link. This extra torque puts an extreme amount of pressure on the front differential cover, more importantly the front differential cover fasteners. All 8, 8mmx1.25mm torx head fasteners will eventually stretch and or back out. Once the bolts have failed, the differential will leak and the complete differential failure is not far behind, unless you can catch it early. Getrag addressed this issue on the 991 Turbo front differentials by redesigning the front differential cover, adding additional bracing and added 1 extra fastener. Confirmation that the 997 Turbo front differential cover fasteners are failing . This is where we have stepped in and created a permanent fix!


You may also need a Wavetrac lsd for the front of your P-car!

Here is a link:


SKU: SD135
  • 2 axles seals
    1 Carrier bearing,1 high load tapered bearing shim kit
    Diff cover o-ring
    High strength locking bolts
    Billet front differential cover