996 Carrera 4 front dif oil seal replacement

[Doohan]

Ok, lift up the car, dry out the diff oil, remove the lower wheel arm and try to get enough room space to pul out the joint

Take out also the 6 screws and nuts fixing the last part of the joint

Now you have enough space to remove all the screws and the dif cover

Clean everything, put the new Oil seal and remount the cover.

Now fill with transmission oil to the level (until oil start to come out from the filling hole) and remount everything in reverse order. you are done!

Edited October 13, 2009 by Doohan

[Xeattle]

Is this just a preventative once you reach a certain mileage or will it help with the transfer of torque to the front. I sometimes wonder if my C4 is really transfering up to 40% drive to the front but I think it has more to do with how warmed up the car is and how well the viscous fluid is thickening up.

What type of fluid did you use and do these front diffs have a limited slip...either physical or virtual?

Great write up...thanks!

:renntech:

Edited October 13, 2009 by Xeattle

[goldenwarrior1]

I believe differential fluid change is part of the 90K mile service. Unlikely changing the fluid will make any noticeable difference to the driver assuming normal wear of the differential.

The 911 Carrera 4 is a four-wheel-drive system with a viscous multiple-plate clutch, the front wheels consistently convey a minimum of 5 per cent and, if required, a maximum of 40 per cent of the engine's drive power to the road. The viscous multiple-plate clutch is housed in the front axle drive unit, conveying drive power to the front axle and compensating for any difference in engine speed between the two axles. Like a multiple-plate lock, the clutch is made up of inner plates fastened to the hub and outer plates connected to the housing. Silicon fluid comes between the plates in a totally sealed compartment. As soon as there is a difference in speed, shear forces between the silicon fluid and the plates transmit torque and drive power to the front axle as required.

B)

[Doohan]

I believe differential fluid change is part of the 90K mile service. Unlikely changing the fluid will make any noticeable difference to the driver assuming normal wear of the differential.

The 911 Carrera 4 is a four-wheel-drive system with a viscous multiple-plate clutch, the front wheels consistently convey a minimum of 5 per cent and, if required, a maximum of 40 per cent of the engine's drive power to the road. The viscous multiple-plate clutch is housed in the front axle drive unit, conveying drive power to the front axle and compensating for any difference in engine speed between the two axles. Like a multiple-plate lock, the clutch is made up of inner plates fastened to the hub and outer plates connected to the housing. Silicon fluid comes between the plates in a totally sealed compartment. As soon as there is a difference in speed, shear forces between the silicon fluid and the plates transmit torque and drive power to the front axle as required.

B)

Nice! Thanks for the perfect explanation!

@Xeattle

I had to change it because of the oil leak...