aTOMic

My newer 2004 (92K miles) rolls an inch or so, even if it's parked on apparently level ground. My 190k miles car doesn't move at all even if parked on an incline.

I always use the parking brake on inclines, however slight. Seldom used it on flat pavement, but now I do in the new car to keep it from bouncing off the parking pawl (if there is still such a thing).

Does anyone notice movement or lack thereof when not using the EPB?

Thanks,
Tom

mishar

Actually your newer one acts normally and the other one is suspicious. There are number of elastic elements and gears taking load in the process so it is impossible not to move at all. Even with parking brake applied it would move a bit while only rear brakes and all rear bushings take all load from front brakes.

TSHong

+1, Mine does not move when I set the EPB, which is all the time. If I forget to set it, it will move a bit like all cars I've ever owned.

If your older does not move, I suspect a sticking caliper on one or more corners.

MP4.2+6.0

Mine moves a few inches, but + 3 on I always set EPB, flat or slope. Just got used to it driving stick. Oh, and same on 2015 S8, or 2013 Q5, or... From rebuilding one W12 front drive axle and replacing CV boots, I can tell you there was probably that equivalent of a couple of inches (at the tire radius) just based on the kind of play I found in the half axles once you run driveline torque through both CV joints and the final diff gears.

aTOMic

Thanks for the replies. I'll check for stuck caliper today by spinning the wheels with it up on a lift.. oh, wait...

I'll get out the old IR thermometer and see if there's any significant differences in rotor temps. Hadn't thought of that. Thanks TS!
The "new" car (Sage) is really clean in appearance but underneath she's a dirty girl... rusty fasteners everywhere, everything not made of Al or well-painted showing signs or attack from her salty prior life which started in Manhattan. The older one has remarkably less corrosion, having in the Midwest and Deep South most of her life. Her dress isn't as fancy as the Sage car, but "she keeps her motor clean", as AC/DC once said. I've often been reminded of certain girls I knew in school by this phenomenon.

Misha, I think these cars would have to be parked on one helluva steep slope to move at all with EPB on, since it acts on the rotors themselves... assuming one set the brake with his foot on the brake pedal. But I agree with you and MP+, there are many, many places for play and elasticity to be allowed into in the complex D3 drivetrain, not the least of which is the large tire circumference. I always thought it was surprising how little the car rolled when parked even w/o the EPB on.

Thanks again, gentlemen.
-Tom

TFT

I never set my parking brake. Part of the reason I got out of the habit was that in Alaska with the extremely cold temps in the winter, setting the parking brake could result in it freezing in place.

aTOMic

I guess it's unnecessary in both your locations; Alaska, your wheels are naturally chocked by the snow, and Arizona is flat as a pancake (except for those rocks the Martians left there).

OT: Have you seen that TV show "Highway Through Hell"? It's a tow company's exploits in Alaska recovering big rigs and their freight. It's pretty interesting to see the effects of gravity and mass as trucks slooowly slide off the highway! They catch a lot of this type footage because the average trucker in AK has an IQ equal to his tooth count, and thinks HIS truck can make it where others are piling up before his eyes.
Sounds stupid, but strangely addictive...
IIRC they're in Palmer, AK, just like you!