Forward/backward 'slop' - 986 Forum - The Community for Porsche Boxster & Cayman Owners

epapp · 08-20-2015, 10:37 AM

I have some slop. I chocked it up to the front engine mount so I replaced it. The slop is a tiny bit better, but the source of such slop was obviously not the front mount.

When I am releasing the clutch in 1st gear from a standstill, everything is nice and tight with my new clutch and engine mount. The slop is felt when I let off the throttle. Its like the car can roll 'freely' for maybe 1.5 inches of road before I can feel the can begin to engine break. Besides gear slop, what could this be?

On a side note, I have also noticed if I am rolling slowly in neutral and apply the hand break gracefully, I will notice a similar sort of 'slop' where the hand break will catch but the car will roll just a bit more before beginning to slow. Maybe related?

EJ-Fresno · 08-20-2015, 10:49 AM

Will follow up on this one, I have the same issue when I pull my hand brake but the car can move back and forth for 1 or 2 inches...

epapp · 08-20-2015, 02:57 PM

Exactly, the car will settle within a few inches of the parking brake being set. Im sure a rear hub disassembly will answer the question, I just have not yet been annoyed to the point of doing it.

I have a feeling they are related because any hub slop will also apply to the slop I am feeling when accelerating and transitioning to engine breaking.

EJ-Fresno · 08-20-2015, 03:02 PM

Now that I am thinking about it, I indeed have a small slop when shifting, whereas I just changed my motor mount...

epapp · 08-20-2015, 03:10 PM

The shifting slop for me is mostly chocked up to my chinese short shifter I think.

But, if it is wet out (we might never have to worry about those circumstances again here) and you begin spinning the wheels in first gear (moderate load on the engine) and you switch gears, you can feel almost a 'spring' motion of the engine back to its resting place. I always thought it was the fault of my old front engine mount. I am out of guesses, unless the two gel tranny mounts have these characteristics when bad..

Dualist · 08-20-2015, 05:12 PM

I've got slop on one side and it's my drive shaft, wierdly it does it even with the handbrake on which is a worry.

jacabean · 08-20-2015, 05:29 PM

I'm not sure if this is the same but when one of my rear wheel bearings was toast the car felt loose and would slow down quickly when I let off the throttle .

epapp · 08-20-2015, 07:06 PM

But I assume when that bearing was bad, you also surely heard and felt it at speed?

jacabean · 08-20-2015, 07:37 PM

Quote:

Originally Posted by epapp

But I assume when that bearing was bad, you also surely heard and felt it at speed?

Did not make any noise but got vibration at 80 mph . The car felt like I was pulling a trailer . Did you look at your axles ? Check the boots on the cv joints. Axle bolts at the diff.

epapp · 08-20-2015, 07:41 PM

I will do that next available chance. 6 months ago the boots weren't torn I know that much.

Sometimes I DO feel like I'm pulling a trailer, but I assumed that's the inherent lack of 700hp.

jacabean · 08-20-2015, 07:54 PM

At least you can rule out anything wonky in the drive line .

Timco · 08-20-2015, 08:18 PM

DMF?

My first thought.

epapp · 08-20-2015, 08:56 PM

I would think that as well but the flywheel is <5k old. And the 'slop' was there before the flywheel change.

:'(

jdlmodelt · 08-28-2015, 07:35 PM

CV's are wearing out or the trans-axle ring and pinon spacing?

Pdwight · 08-28-2015, 10:44 PM

complete axles are dirt cheap if that is the problem.....pull them and take the joints apart and look for egg shaped balls or the races showing wear...if so I would buy a complete axle ready to drop in....100 bucks per side roughly

Deadeye · 08-29-2015, 04:08 AM

If the engine mount was tired the trans mounts are probably warn as well.

jakeru · 08-29-2015, 11:14 AM

Try jacking up one rear wheel with other on ground, with engine in gear, and then you can get a feel for the rotational play/slop in the jacked wheel, and possibly identify looking under the car if it's coming from a particular cv joint. You could even measure/quantify the play/slop using a protractor. Try shifting to different gears, re-try the slop test, to see if it's worse or better in any particular gear. If all the cv joints are tight and the slop is the same in all gears, I'd think it would be the differential, transmission R&P, or perhaps a loose dual-mass flywheel, or a combination of the above.

This test probably won't put enough loading to test for loose motor/tranny mounts, so if it seems "tight" according to this test but loose when you drive it, the difference is probably the motor or tranny mounts. (Or perhaps, even something that has has more to do with causing poor throttle response than actual mechanical driveline play - such as a sticking motorized throttle assembly that needs cleaning.)

It's also very possibly a combination of multiple of these factors. Cv joints could be a good first place to look. I'd expect brand new cv joints to be definitely tighter than used cv joints with any miles, or aftermarket "remanufactured axle" (which probably re-use cv joints of unknown original, with unknown number of miles and wear on them, which would almost certainly not be as tight as brand new cv joints, or a brand new axle assembly).

Hope this give some good food for thought.

Dualist · 11-15-2015, 07:27 AM

Quote:

Originally Posted by Pdwight

complete axles are dirt cheap if that is the problem.....pull them and take the joints apart and look for egg shaped balls or the races showing wear...if so I would buy a complete axle ready to drop in....100 bucks per side roughly

Where is that from.? And do they ship to the UK.?
I've tried shafts from breakers but they are even more worn than mine, I'm starting to hear a rattle off load and I know my outer cv's have a egged or flat spotted.