Diff Seal replacement while changing CV boots
#1
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Curious if the front diff seals need to be replaced when removing the cv axles as I need to replace the front CV axle boots on my 997 4S model. And if there are any gotchas.
Thanks for any input
Thanks for any input
#2
Rennlist Member
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**When you change the differential fluid, make sure you use the correct type.
My memory is failing me at the moment but there are Threads on this - I believe special 90W oil
My memory is failing me at the moment but there are Threads on this - I believe special 90W oil
#3
Rennlist Member
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I've rebuilt the front axles on two 997s without replacing the diff seals or fluid.
I struggled with the rebuild because I couldn't get the inner race of the inner CV off of the axle. I even used heat and a three leg gear puller without success. My independent mechanic used a heavy hammer to knock the outside CV off of the axle. It is held on by a internal, circular, round wire spring clip. In one case the spring clip was damaged. This clip in not in the PET. I searched everywhere and couldn't find a proper replacement. Eventually I found one close in size (correct wire diameter for the groove but too large for the axle diameter) and modified it to fit. That worked like a charm.
I struggled with the rebuild because I couldn't get the inner race of the inner CV off of the axle. I even used heat and a three leg gear puller without success. My independent mechanic used a heavy hammer to knock the outside CV off of the axle. It is held on by a internal, circular, round wire spring clip. In one case the spring clip was damaged. This clip in not in the PET. I searched everywhere and couldn't find a proper replacement. Eventually I found one close in size (correct wire diameter for the groove but too large for the axle diameter) and modified it to fit. That worked like a charm.