I've had my '05 CTT for about 6 months now. I've done Hanksville secondary bypass pipes and Magnaflow exhaust, Softronic tune, lowered with Durametric, and a bunch of maintenance stuff.

So I have a couple questions that I seem to keep coming up with but don't find any answers here. Ok, actually I have three questions.

First should be simple. We don't get a lot of snow where I live, but it does happen a couple times per winter. We had some really heavy frost and ice a few weeks back and the beast seemed a bit skittish. What kind of settings do you guys who drive in the snow all the time use? Is it feasible or would it help to lock the rear diff? I really haven't played with that **** at all yet.

Second, I seem to get a bit of a groan almost when leaving from a stop. I changed the valve body in the trans out and have done the fluids in the transfer case and both diffs. The best I can explain this is it feels like it's coming from the left front somewhere. I don't feel it in the seat of the pants or in the shift lever, more in the steering and feet. I've heard the front diff on these makes some noise but not sure if that's it or not.

Last, I seem to be having issues not developing enough boost. I started making some test fittings but never really figured out where to hook it all up. Does anyone have some pics of how and where to hook them up? Also I've been trying to figure out how to capture data-logging with the durametric. I've played with it some and I know it will show real time data for a LOT of things including boost levels. How do you capture that though, it seems to only show what's in the time window and then stops altogether once you shut the car off.

Thanks all and hope you have all had or are having a Very Merry Christmas!!

John

 

First of all, once you start to talk about ice, all bets of off unless you chain up on all four or have studded winter tires. For light to moderate snow, just leave in full auto, no locked diffs. The Cayenne is really really good at finding traction with its all time 4WD and PSM. If your Cayenne was skittish, I am sure it is due to the fact that you could use a good set of narrow, winter tires (softer tire compound, tire siping to increase grip).

My Cayenne is sure-footed in the snow and I often go WOT with PSM off/on since it is controllable with steering correction. It is up to you to justify the costs. For me, the safety of my family merits the minor expense of winter wheels.

Also, unless you have the Advanced Offroad package (almost no one does), you only have a locking front diff and center diff. Only engage these in very deep snow, with suspension up, and PSM off (wheel speed is your friend).


No idea here..

Yes, I made a boost leak tester when I made my larger y-pipe plenum. There are a few pics on that thread that shows it hooked up to both MAF housings. I will find the pics and post them here.

Once you select the data you want to capture and it shows in the window, it is logging. Once you are done with your test run, select the tab to the right to export to a "CSV" file. From there, you can open it in Excel and view the data. All of this has to be when the car is running.

I have several values that I capture, that I will look up and forward on to you.

 

Here you go...

 

Thanks Kent. Great help and info as usual.

As for the tires, yeah I had regular tires on because I'd been debating whether to go up in rim size and just get all season tires or what. I decided to just throw some winter tires on the stock 19" rims and then in the spring probably buy 20" rims and tires.

The durametric I had been playing with it in the garage the other night, but I couldn't figure out how to export it. Thanks, that makes it easier.

I'll see what i can come up with for the boost leak tester. It sure either isn't holding or not getting up there for some reason. It just seems to me like it's leaking because it will initially run right up to peg the needle but then pretty quickly falls back down below .8bar.

Thanks again for the help!!