Hopping and knocking from AWD?

[ajpturbo]

Had a little snow last night and was playing around and testing the AWD. Had the advance trac light flicker a few times so I know I was spinning and sliding and had the system activated.

Got home and pulling in the driveway and had the wheel turned full lock to the right and about every 8 ft of rolling the front tires would skip and hop. Put it in reverse and the same thing. It felt and sounded like a 4wd truck with solid axles and U joints on the steering knuckles that hop and buck when steering is turned to full lock.

I pulled in the driveway immediately after spinning in the snow. Does it take some time with normal traction to return the awd to normal? I know some of the old trucks needed to drive a little and sometimes even in reverse to fully unlock 4wd even after unlocking the hubs.....I know these are different systems and the SHO awd is passive and doesn't require user action but it acted much like a solid axle that skipped and bucked.

 

[SHOdded]

Unless there was a regular sudden bump on the road every 8 ft, I'd have the system looked at.  Did you have the halfshaft check performed at the dealer?

I assume you have a '13+?  No sig

 

[ajpturbo]

Yes 14' PP. Yeah I looked at the halfshaft it's fine...JMR gave me the TSB and the actual repair/inspection percedure. It has pics no big deal. I'm qualified for the inspection lol.

No bumps, I sat in the driveway rocking the car forward and reverse and it kept doing it. 1mph rolling. Its just like a 4wd truck...I'll go drive it a little and see if it goes away.

 

[slurppie]

I've noticed this same "feeling" and have been able to reproduce it while turning  on wet leaves. Combine cold temps and summer tires and you end up with loss of traction.

 

[IHeartGroceries]

Unusual. Nothing on the SHOs AWD system should be "locking". And unless I am mistaken, both the front and rear cases are open.

Sent from my SM-N900V using Tapatalk

 

[SHOnUup]

Is it felt in the steering wheel only, or in both the steering wheel and suspension?

Rich

 

[slurppie]

Are you sure it's mechanical and not just the front "pushing" I.e. Loss of traction?

 

[wasinger3000]

If it was my car I would take it in. I was just out playing in the snow this weekend and my car did not do anything like yours. I turned my traction control off and did plenty of slides without an issue on dry pavement afterwards.

 

[12sho]

Mine did that..... Was bad ball joints

 

[ajpturbo]

I doubt it's bad ball joints. I've got 5k miles on it. It's audible and I feel it in the wheel. It's weird, just like the bucking you'd feel in a shitty 4wd in a full size truck lol...I thought there was some kind of e-locker or something or a solenoid like in the PTU to activate the rear.

I'll drive it tonight or early tomorrow and see if it's still there. I literally just pulled in the driveway and was parking after driving pretty wildly in the snow. That's why I was thinking I didn't give something enough time to deactivate or unlock or something.

When I stick my head out the window and watch the tire I see it skip. Its gotta be drivetrain related.

 

[SHOdded]

It IS possible you have been successful in getting the ABS to lock up/Advancetrac to "fail".  Normally with Advancetrac you will hear more of a grinding/crunching noise as it gets activated and shifts speeds around the wheels.  Did you happen to check the tie rods by any chance?  Yes, they have been known to fail early!  I think ShoBoat had to replace one on his '13 at around 10K ...

 

[SHOnUup]

Almost sounds like an axle related issue. If not the front diff, maybe a half shaft lost a tooth from spinning on snow to gripping pavement. This type of driving plays havoc on AWD systems throwing power to the corners to correct the spin.

Rich

 

[FracaSHO]

What about snow buildup in the wheel well? Remember "My Cousin Vinny," when he got mud the tires.

 

[ajpturbo]

Its gone...drove it up the road and to a parking lot...something was locked in the front part of the diff or transaxle or maybe even more likely the ptu. Ill have to look in the manual to see if it mentions driving a short distance after stability control has been activated to return to normal operation...i literally was spinning and sliding around when i was playing on my street and immediately parked the car....im sure thats what it was. The awd relys alot on electronics in this car kinda like an e-locker for clutch packs so i think something was still locked i dunno....i know some will say huh mine doesnt do that but things in my experience when they are truely broken dont randomly start working so this seems to be by design and i mustve produced a sitution or paramters in the system that caused it.....many of you have not scene the scalars and tables in the tune for awd function...it would blow your mind..especially with calibrator level access which opens even more tables

 

[FoMoCoSHO]

Its gone...drove it up the road and to a parking lot...something was locked in the front part of the diff or transaxle or maybe even more likely the ptu. Ill have to look in the manual to see if it mentions driving a short distance after stability control has been activated to return to normal operation...i literally was spinning and sliding around when i was playing on my street and immediately parked the car....im sure thats what it was. The awd relys alot on electronics in this car kinda like an e-locker for clutch packs so i think something was still locked i dunno....i know some will say huh mine doesnt do that but things in my experience when they are truely broken dont randomly start working so this seems to be by design and i mustve produced a sitution or paramters in the system that caused it.....many of you have not scene the scalars and tables in the tune for awd function...it would blow your mind..especially with calibrator level access which opens even more tables

Do tell.....

Are you tuning your own car?

 

[IHeartGroceries]

Tell me more about what locks.