Mike in CA

Cool, Strimdog! Hope you post pics of your new wheels. If you're like me, the most satisfying part of doing the CL's for the first time is the realization that while some care is required, it's not rocket science and well within the capabilities of someone who can handle a wrench.

Strimdog

I will definitely post my experience as well. I'm counting on "it's not rocket science and well within the capabilities of someone who can handle a wrench." otherwise I'm gonna have car in my garage without wheels. This would be problematic.....

SmokinGTS

I would like to add one important point for those guys who have not done this before. You need to torque the nut with the wheels off the ground. Torque them to the required torque and then back off the wrench 1/8th turn and re-torque to the 440 ft pounds...This is an easy job, I just hate the anti seize compound. Nice write up...

CodeRed

Thx much, where is the best place to buy the "special" CL torque wrench?

mdrums

Mike...you can use the Precision Torque Wrench to remove the center locks too...it torques both ways...so the breaker bar isn't really needed.

Per the instruction manual and per talking to Porsche engineers you should always have someone pushing the brake pedal or have a tool like a truck brake press tool or the mentioned Irwin clamp to firmly press the brake pedal. Never rely on the PDK transmission and parking brake.

I've been dealing with Center Locks since September 2011. Taking them on and off to service my brakes and swap wheels for track use...many times a year. If you have any questions let me know. When you are ready to take the actual center lock nut apart let me know and I will send you the pages from the workshop manual...it's silly easy BTW.

rubbaman

Great job Mike! You are faster at it than me. My best lap time around the car was 45 min!
Pictures were great! It happened!

bronson7

Much appreciated effort Mike. My time will come. Thanks.

Mike in CA

Off the ground, absolutely. Anyone who does this themselves should follow the steps in the owner's manual carefully. BTW, both the owner's manual and workshop docs for the 991 GT3 specify backing off by 1/4 turn after torqueing initially, rather than 1/8 turn, and then re-torqueing. Maybe the spec was different for the 997.

Thanks, Mike. I initially thought I might use the wrench itself if necessary as when assembled it's longer than the breaker bar, but I was leery of doing that after I read the directions which state that it shouldn't be used to break nuts. I wasn't sure how to configure it to be certain of not causing it damage but as it turned out the breaker bar which I'd already purchased worked just fine.

I defer to you on the time Rob; I was just making a SWAG based on one wheel. Besides you averaged 11 1/2 minutes a wheel which is "around" 10 minutes. And I have yet to prove I can do a 45 minute lap in real time!

PC Valkyrie

I have a question about loosening or tightening the centre wheel lock with the wheels off the ground (and possibly having somebody or a tool pressing on the brakes).

Is a floor jack strong enough to keep the car up while you tighten or loosen these centre wheel locks given the very high torque required? And add to that the possible need for somebody to physically step on the brake pedal at the same time (if you don't have that special tool to press on the brake pedal)?

Is there any danger of a floor jack not being strong enough to keep the car up with all those forces acting on the car?.......or am I completely off base here?

I routinely change tires with a floor jack alone, without jack stands.......but that is with standard 5 lug wheels on my other cars and I torque the lugs with the wheels on the ground in a star pattern.

Mike in CA

The chassis of the 991 is very stiff so lifting one wheel off the ground takes most of the weight off the other wheel on that same side; you're effectively nearly lifting one whole side of the car. Not accounting for the fact that some weight is being transferred to the wheels on the other side, let's keep it simple and assume in a worst case scenario that you're lifting 1500 pounds of a 3200 lb car.

Many floor jacks, like mine for example, are rated for two tons. That leaves a 2500 pound safety margin. The weight of a passenger plus the torque being applied to the wheel are no cause for concern as far as the strength of the jack is concerned. The car should be secured in park, with the brake on, and/or with the brakes secured to make sure that it can't move while on the jack.

Money2536

Thanks for posting Mike!

bronson7

Can you still just crack/loosen the centre lock nut with the wheel on the ground? Once loose, proceed to jack the wheel up then completely remove the nut/wheel. So the weight of the wheel on the floor helps with the torque one must apply to crack the nut.

ranger22

And the corvette forums ridicule us for applauding someone for taking off their rear wheel! Woohoo!

Great write up though! So easy!

Zulu Alpha

Mike this is fantastic! I love it when you post stuff like this!

aeGT3

Thank you Mike for sharing your experience with us with lucid description and pictures. It is refreshing to have posts like these that are more useful and informative than endless bickering over the merits of manual transmission vs PDK-S