Hi (new) friends. I'm looking at several 955 CTT/CTTSs and am certainly ordering PPIs for any I get serious about, but I'm also a pretty experienced wrench myself and would like to see what the recommended PPI points are on a 955 CTT/CTTS. I've done a little searching on the forum and a bit of Googling, but haven't come across anything concise.

Likely due to poor search skills on my part but if someone has a link or a good PPI checklist specifically for the 955/957, I'd be grateful. I'm looking at a 955 CTTS this weekend and would at least like to make sure I do a fairly thorough PPI before I arrange to have a shop to the full PPI. @TomF , I suspect you of all folks can find this.

Thanks in advance,
Matt

 

@Imhighlander, Best of luck in your search. I just got an 09 GTS myself a couple months ago and after a long search (l was super close to one in Florida), I found one locally. I usually keep my cars for a long time and spent a lot of time and effort on them, so I go for the lowest mileage within reason. This time, I got one with a ton of miles (122K), but I got it cheap and after a PPI, I knew I'd have to sink some money into it. It didn't run right and I heard the clunk under the floor, the power steering line was leaking as well. While I don't have a big check list for you to print out, I have learned a ton about the car in a short amount of time. First, get records. It goes without saying but after I changed all the fluids, I left the transmission fluid to the experts. Mine didn't come with many records, and the condition of the bolts on the tranny made us (mechanic and myself) think it hadn't been changed. Short story is that it looked good, so most likely it had. That's about $500 I can't get back, but I guess it's good peace of mind... The major expense on these is the drive shaft, high pressure fuel pump and other 2 fuel pumps (inc. filter), which all go bad on all 955/957, period. You'll be miles ahead if you have a record as to when those have been changed. The rest of the stuff is small and if you wrench yourself, like I do, they are pretty easy to work on. I'm changing the sway bar bushings this weekend and I've done a fair amount of small stuff to get it back to top form. It's a kick *** ride and you'll enjoy it when you find the right one! Best of luck!

 

This has been my experience as well. I have an '05 VR6 with over 170k. I bought it with a little over 82k and put the rest on myself. In my experience they're pretty easy to work on. The big trouble spots are the early non-turbo V8 motors, which have a significant percentage of catastrophic high-mileage bore scoring, especially in cold-weather areas. I've done the drive shaft and the in-tank fuel pumps on mine, and they were both pretty easy jobs. You can always Jimi Fix the drive shaft, and the fuel pumps were only a bit fiddly. I haven't done the high-pressure pump, but that one looks like a job for someone with small hands.

I fully expect to take my Cayenne to 200k, and I don't expect to spend a lot to do so.

To your original question about a PPI checklist: We don't really have one. There are a few known trouble spots (like the bore scoring, and the transmission valve-body, roof drains), some wear-out items (drive shaft support, fuel pumps), and some things to avoid (panoramic roofs). But overall these trucks are as close to bulletproof as you're ever going to find. They're also common enough that spares are easy to come by (I replaced an entire door with one from a wreck in a couple hours, the door cost me a few hundred $$$).

Good luck with your search!

 

What did the clunk turn out to be? I have a clunk in mine when i got on/off the gas when turning, or during a direction change. Had it up on the lift and everything seems fine so still trying to chase it down.

 

@rsinghal3, If the clunk is coming from under the car, specifically what feels like someone hitting a hammer under the center console, it's the driveshaft that's going to need to be replaced. The bearing wears out. I especially noticed it when hitting the gas while turning or right after the turn.

 

Do a search for the transmission valve body problem, that will give you clunks when the transmission downshifts at low speeds. When the driveshaft goes, you at first get a 'whummering whummering' sound, and when it completely goes it's like someone hammering on the underside of the center console, especially during acceleration.

 

Appreciate the responses on this. We did check the drive shaft pretty thoroughly and did not find any play. The main time I hear it is on/off gas - sounds like play in the drive train or something. I will take a look at the valve body and I also had a suspician maybe the stepper motor in the transfer case could be causing this? Had tires and alignment done in the last week so do not think that is the problem.

 

Sorry Matt! I am striking out on a PPI checklist. I suspect it's because the Porsche material is all copyrighted and the power-that-be are litigious-averse... and rightly so. Feel free to reach out if you have any questions while they are in the thick of the PPI. You have my cell...

Cheers,
Tom

 

Thanks for the responses. I'm a pretty experienced (battered?) wrench myself. I have a rough PPI checklist from Pelican and I will put something together from the 2020 Porsche Buyer's Guide that Excellence publishes. I'll be developing my own PPI checklist to use for one I'm checking out tomorrow and will happily post up my process in hopes that through the forum we can gradually develop a resource other Porschephiles can leverage in the future.

One thing I've learned over the decades is that if there aren't receipts for the work, assume (and negotiate as if) it didn't happen. I do most of my own work but I keep all records in a binder for each vehicle with notations on the dates and mileages when things were done. (Not with routine oil changes, but literally everything else.) Records sell the car. Otherwise, I negotiate significant discounts or walk away.

 

Alright, friends. This is what I've created to take me into tomorrow's "DIY PPI." If anything stands out that I'm missing, I'd covet those suggestions. If it's ready to rock, feel free to use for yourselves. Will report back with tomorrow's findings.