DCT Acting Weird During K Turn Into My Garage ?
#1
Race Director
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DCT Acting Weird During K Turn Into My Garage ?
The last couple times I came back from a ride I got a strange sort of clunk and bind from the DCT while K turning into my garage. I have to do a few lock to lock K turns to enter my garage and center the car perfectly on the runways for the lift. If I have the wheel locked right and then turn to the left lock position and put the car in reverse and back up when I put the car back in drive it's almost like the hill assist stops the car. I do have a bad habit of sometimes shifting while the car is slightly moving which is almost subconscious. I'm thinking that it's some sort of mixup with the DCT and the hill assist. The DCT shifts perfectly otherwise from what I can tell. Anyone else experience anything like this ?
#2
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The sound you are hearing may be from the tires at max angle rather than the DCT. Big tires have a tendency to do that - especially when cold. Had that a lot with my C6s
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Sin City (02-22-2021)
#3
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I was thinking it might be something like that too... The other thing I should have mentioned is that the front lift is always raised entering my driveway and garage for the ramps to the lift.
#4
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The Owner's Manuals discuss this.
#5
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#6
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Modified C8 of the Year 2021 Finalist
I got curious and went looking too.....the only thing I found was this, which I don't think comes close discussing your experience....
"Dynamic Rack Travel
If equipped with Magnetic Ride Control, Dynamic Rack Travel (DRT) is a steering system feature which enhances driving by providing additional maximum steering wheel rotation to allow a tighter turning radius during low speed driving conditions. If the vehicle speed increases or if the suspension encounters significant wheel travel, such as a driveway, while at maximum steering rotation, DRT may gently push the steering back a small amount to prevent the front tires from contacting the vehicle. This is normal operation. There is no customer interface or display for this feature. DRT is not available when in Track Mode."
"Dynamic Rack Travel
If equipped with Magnetic Ride Control, Dynamic Rack Travel (DRT) is a steering system feature which enhances driving by providing additional maximum steering wheel rotation to allow a tighter turning radius during low speed driving conditions. If the vehicle speed increases or if the suspension encounters significant wheel travel, such as a driveway, while at maximum steering rotation, DRT may gently push the steering back a small amount to prevent the front tires from contacting the vehicle. This is normal operation. There is no customer interface or display for this feature. DRT is not available when in Track Mode."
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djkianoosh (02-23-2021)
#7
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I don't have MRC but I think something like this is happening...
#8
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C7's had the same issue only much worse. I feel this one when reversing only. IMO its for sure the tires.
#9
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I found this on the mid engine corvette forum... I guess it's normal...
https://www.midenginecorvetteforum.c...most-full-stop
https://www.midenginecorvetteforum.c...most-full-stop
#10
If I have the wheel locked right and then turn to the left lock position and put the car in reverse and back up when I put the car back in drive it's almost like the hill assist stops the car.
FYI...When I worked at a Sears Auto Center (remember them)I was told to advise customers to always have the vehicle moving, if only slightly, whenever turning the wheels so as to avoid "scrubbing" the tire rubber.
#11
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I found this on the mid engine corvette forum... I guess it's normal...
https://www.midenginecorvetteforum.c...most-full-stop
https://www.midenginecorvetteforum.c...most-full-stop
Do you have the z51 as well?
#12
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I think the front lift has something to do with it. Just like problems that occur with lowered and lifted vehicles. I'm going to lower the front while making the K turns and then raise it before I approach the ramps. I probably don't need it for the driveway or the lift ramps anyway. I'll also not turn to full stop and just do one extra K turn. It doesn't sound or feel good so I'm not going to try to recreate the problem...
Last edited by EasyLivin; 02-22-2021 at 07:51 PM.
#13
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If the OP wants to know why it occurs this is my revised PDF on the subject: http://netwelding.com/Wheel_Chatter.pdf
For tech folks it has a revised 4 page appendix that reviews Ackerman steering compensation and why some race cars have very little or no Ackerman steering compensation. They live with slow speed chatter say coming out of the pits so they can get max lateral "gs" in high speed turns.
#14
Instructor
holy cow.. great info in this thread. I have magnetic ride on my Audi TTRS and I think this explains what I hear there too. Good stuff!
#15
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I was able to get up on the lift today with the front end lifted but I didn't turn to lock in either direction and made sure not to scrub the tires and everything was fine.
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