Pelican Parts
Porsche Parts Catalog Accessories Catalog Porsche How To Articles Porsche Tech Forums
Call Pelican Parts at 888-280-7799
View Recent Cars  |Shopping Cart Cart | Project List | Order Status | Help
 >  >
Driveshaft Bearing Support and Flex Disc Replacement
 

Pelican Technical Article:

Driveshaft Bearing Support and Flex Disc Replacement

Jared Fenton

Time:

1 hour1 hr

Tab:

$430 to $540

Talent:

***

Tools:

13mm, 15mm socket, 5mm hex driver, 18mm wrenches, razor blades, Air grinder, Sawzall or hacksaw.

Applicable Models:

Porsche 955 Cayenne (2004-10)
Porsche 955 Cayenne GTS (2008-10)
Porsche 955 Cayenne S (2003-10)
Porsche 955 Cayenne Turbo (2003-10)
Porsche 955 Cayenne Turbo S (2006-10)

Parts Required:

EPS Driveshaft Support

Hot Tip:

Wear safety glasses when cutting old support

Performance Gain:

Smoother driveline

Complementary Modification:

Change transmission fluid

The driveshaft center bearing support is used to dampen vibration and lateral movement of the driveshaft as it spins. The factory design of the rubber seems to be a bit weak for the job, usually resulting in the rubber cracking or tearing due to age and the elements. When the rubber starts to fail, you'll notice an odd vibration coming from the center console when accelerating. This vibration will only get worse over time, eventually turning into a loud knocking noise.

The factory fix for the support is to remove the driveshaft from the car, disassemble it and use a new center support (with the same rubber centered design) when reassembling it. EPS has devised a solution that does not require driveshaft removal, and does a better job of supporting the driveshaft.

The EPS solution re-uses the bearing already on the driveshaft. You'll want to check that the bearing is still in good shape once you cut away the rubber. It should spin freely, with no binding or noise. If the bearing does any of these things, its finished and you'll have to install a rebuilt driveshaft or remove the existing driveshaft and have a new bearing installed. Hence, why you should inspect the support if you start feeling an odd vibration.

In this article, we will go over the steps involved with removing the old support and installing the EPS support. Additionally, we will go over the steps with replacing the front flex disc on the driveshaft.

The flex disc is a rubber reinforced coupler that isolates vibration from the rest of the drivetrain, while transferring power from the engine and transmission to the rear differential and wheels. When the center support begins to fail, it can put increased stress on the flex disc, causing it to crack. Over time, the cracks grow due to centrifugal force and can eventually fly apart in chunks if they are seriously neglected. The EPS package includes a new flex disc if yours is worn.

Begin by jacking up your Cayenne and placing it on four jack stands rated for at least 6000 lbs. (See our article on Jacking Up Your Cayenne for more information). You'll need to jack the car high enough to access the center underside.

Begin by removing the six 15mm bolts (green arrows) holding the support plate to the chassis.
Figure 1

Begin by removing the six 15mm bolts (green arrows) holding the support plate to the chassis. Then remove the two 13mm bolts (yellow arrows) holding the driveshaft bearing support to the support plate.

Shown here is the driveshaft bearing support.
Figure 2

Shown here is the driveshaft bearing support. You can see the tear in the rubber mount (green arrow). You'll want to cut through the remaining rubber so that you can slide the outer metal sleeve towards the front of the car.

Slide the outer sleeve towards the front of the car.
Figure 3

Slide the outer sleeve towards the front of the car. You'll need the access in order to cut through the sleeve.

The outer sleeve must be cut through in order to remove it from the driveshaft.
Figure 4

The outer sleeve must be cut through in order to remove it from the driveshaft. An air grinder as shown here makes short work of this job. You can also use a Sawzall or even a hacksaw if needed. The idea here is to make one cut through and then bend the sleeve to clear the driveshaft.

Shown here is an example of the cut you need to make (green arrow).
Figure 5

Shown here is an example of the cut you need to make (green arrow). Once cut, bend the sleeve to clear the driveshaft.

Use a razor blade to cut away the remaining rubber on the bearing.
Figure 6

Use a razor blade to cut away the remaining rubber on the bearing. At this point, check that the bearing spins freely and doesn't bind or make noise. If the bearing shows signs of failure, you'll need to stop now and remove the entire driveshaft.

Shown here is the bearing after a good amount of the rubber has been cut away (green arrow).
Figure 7

Shown here is the bearing after a good amount of the rubber has been cut away (green arrow). The idea here is to remove as much rubber as you can until the outer bearing surface is smooth. A few patches of rubber aren't going to hurt anything.

Here is the improved center support sleeve as designed by EPS.
Figure 8

Here is the improved center support sleeve as designed by EPS. As you can see, the bearing is manufactured in two pieces, allowing you to clamp it over the existing bearing on the driveshaft. The inner sleeve is supported by polyurethane bushings instead of the solid rubber design.

Slide the upper part of the EPS support up and over the center bearing (green arrow).
Figure 9

Slide the upper part of the EPS support up and over the center bearing (green arrow). Note the orientation of the support. It has to go on in the direction shown here.

Attaching the lower part of the EPS mount uses two mounting holes and two channels on either side.
Figure 10

Attaching the lower part of the EPS mount uses two mounting holes and two channels on either side. Use a long shaft 5mm driver as shown here to route the screws up through the plate (green arrow) for the inner sleeve and the channels on the side (yellow arrow) for the outer sleeve. The longer supplied screws fit into the inner sleeve, while the shorter screws fit into the outer sleeve. Once the lower part of the mount has been attached, tighten the 5mm bolts.

When re-installing the support plate, thread the outer, 15mm bolts in first (green arrows) and torque them to 60NM (44 ft/lbs).
Figure 11

When re-installing the support plate, thread the outer, 15mm bolts in first (green arrows) and torque them to 60NM (44 ft/lbs). Then install the two 13mm bolts holding the EPS support to the support plate. You may have to move the mount around slightly for the holes to line up. Torque the 13mm bolts to 20Nm (15 ft/lbs).

Shown here is the new flex disc supplied in the kit from EPS.
Figure 12

Shown here is the new flex disc supplied in the kit from EPS.

The flex disc is bolted to both the driveshaft and also the output shaft of the transmission.
Figure 13

The flex disc is bolted to both the driveshaft and also the output shaft of the transmission. You'll want to inspect it thoroughly for cracks around the bolts and also the outer edges. If the flex disc shows any signs of wear, replace it.

Loosen and remove the six 18mm nuts and bolts holding the flex disc between the output shaft and the driveshaft.
Figure 14

Loosen and remove the six 18mm nuts and bolts holding the flex disc between the output shaft and the driveshaft. These will take a bit of muscle to break free. If you don't have an impact wrench, I recommend putting the parking brake on and even having a helper press the brakes when attempting to loosen the bolts. Then you can also have the helper let off the brakes so you can rotate the drive shaft for better access to the bolts. Once the new flex disc is installed, Torque each nut and bolt to 30Nm (22 ft/lbs.) and then turn each bolt an additional 90 degrees.

Comments and Suggestions:
Do you ship to England? Comments: Good advice I will like to try this.
September 20, 2017
  Followup from the Pelican Staff:
Thanks for the feedback. Glad we could help.
- Nick at Pelican Parts
 
Matt Comments: This fix works. I did this a few weeks ago on my 2009 Cayenne V6 with 59k miles. I have put about 150 miles on the car so far and driven at all speeds and so far so good. It took me about 1.5 hours in total but I was taking my time and taking breaks. The porsche dealer in Houston, TX quoted me $2,800+ to do the repair, how ridiculous… My support failed all of a sudden with no warning, it sounded like there was someone banging a hammer right underneath my center console when I accelerated. I was fortunately 0.5 mile from my home so I did not have to drive the car far.

I ramped the rear wheels of the car and crawled underneath. Unbolted the plate, did not need any leverage to do this. Slid the failed support forward and used an electric cut off wheel tool to cut the failed support off. I picked this cut off tool up at Harbor Freight for $20. I would highly recommend having a cut off tool to do this job, it would have taken hours at an awkward angle to use a manual hacksaw to cut through the failed support. Knowing what I know now I would never attempt this DIY without a cut off tool.

Once the failed support was off I used a razor blade to cut the rubber off of the bearing, this is what took the longest. I got the bearing cleaned up to where you couldn't see any rubber on it anymore, which was probably overkill but I wasn't in a hurry. After that I clamped the new part on and bolted it together, then bolted the plate back on and I was done.
I did not repack the bearing because mine spun freely with no noise and I did not want to risk damaging the seals by repacking it with grease. My thought was if the support had never failed I would have never repacked the bearing. I did not replace the flex disc either, mine was in good shape and didn’t have any cracks that I could see. If it isn’t broken, don’t fix it. I put it on the shelf and can always use down the line if an issue arises. Good luck!
January 31, 2017
  Followup from the Pelican Staff: Thanks for sharing your installation process and experience. These type of comments add so much to the Pelican tech community.
- Nick at Pelican Parts
 
pappapratt Comments: when replacing the flex disc, does the driveshaft need to be realigned?
June 18, 2015
  Followup from the Pelican Staff: The article doesn't mention it. I would think no. If you have a vibration, I would inspect the bearing and driveshaft balance is possible. - Nick at Pelican Parts  
Subi Comments: Hey, I need one of these parts and I'm in Canada. How much is the shipping charge for me to get that here
April 13, 2015
  Followup from the Pelican Staff: There are multiple shipping options. Please give us a call and we can calculate that given your exact location. Please do not post your address on this forum!! 888-280-7799 - Casey at Pelican Parts  

QUICK LINKS
About Us
Careers
Pelican Parts, LLC
1600 240th Street
Harbor City, CA 90710
Order Online or Call:
888-280-7799
CONNECT WITH US
NEWSLETTER
Sign Up for Pelican Pit Stop News & Special Offers
Page last updated: Fri 12/15/2017 02:33:56 AM