Another silverado rolling in park

[sliding silverado]

this happened once before last year and thought it sliding due to ice .

 

well I got it on video the truck is in park and it's rolling down the driveway .

 

and today driving I was on a slight hill in drive and with foot off the brake tje truck is rolling backwards 

[Transient]

Are you putting the transmission in Park? My driveway has an 8% slope, and I've never had this issue. I put my truck in Park and engage the parking brake every time. I've never had this issue. Biggest reason I ask if you put your truck in Park is due to your rear wheels moving in that video. In Park the rear wheels should be locked. This looks like your truck is in Neutral. The difference between you and me is i don't get snow where i live. 

 

 

 

 

 

 

 

 

 

 

Edited February 8, 2023 by Transient

[sliding silverado]

yep 100% in park! and today started rolling back while in drive, with the foot off the brake. 

 

 

 

 

 

 

[eppieguy]

Sure looks like it's the passenger side rear tire sliding on the snow or ice to me.

[Silverado4x4]

40 minutes ago, eppieguy said:

Sure looks like it's the passenger side rear tire sliding on the snow or ice to me.

You can't see the passenger side rear tire in the video but I do think it was sliding back on the ice otherwise it would have kept rolling like if it was neutral. I do know if I don't apply the e-brake and it's in park on my truck if I rock the truck pushing it back and forth the e-brake automatically comes on.

Edited February 8, 2023 by Silverado4x4

[silveradosid]

putting it in park does not lock the rear wheels just the driveshaft. emergency brake will lock the rear wheels. my driveway is a 6% grade and my truck has done this twice. both times i had used 4x4 to get in the driveway and then shifted back to 2 wheel and even though it said shift completed some how the transfer case is staying in neutral and lets the truck roll out the driveway

[asilverblazer]

23 hours ago, sliding silverado said:

today started rolling back while in drive, with the foot off the brake. 

Not relevant, the parking pawl isn't engaged. Depending on the slope its normal.

Edited February 9, 2023 by asilverblazer

[Jus Cruisin]

That's kind of why there is that thing called a parking brake. 

[diyer2]

Use the parking brake.

[asilverblazer]

18 hours ago, Silverado4x4 said:

You can't see the passenger side rear tire in the video but I do think it was sliding back on the ice

One tire stationary (or sliding on ice) and one spinning would be normal operation of the drivetrain when in park. Use the parking brake and/or engage 4 wheel drive to 'lock' more wheels. 

[jaxcam02]

4 hours ago, asilverblazer said:

One tire stationary (or sliding on ice) and one spinning would be normal operation of the drivetrain when in park. Use the parking brake and/or engage 4 wheel drive to 'lock' more wheels. 

yup. hell a quick google search brings up plenty of explanations for this phenomena but anyone who has worked on cars with wheels off the ground should know this basic function of differentials.

 

https://www.quora.com/Why-might-wheels-turn-when-the-car-is-in-P-park#:~:text=Due to the way the,also be able to turn.

 

The transmission does “lock” the drive axle, yes. However it only locks the axle and since there is a differential, even when locked, the wheels will spin freely in opposite directions. For example, if you place the car in park on an incline and one wheel is on ice, and the other is on pavement, the car could still move. The tire on the pavement would roll downhill will the tire on the ice would spin uphill. This is in contrast to using your parking brake where each wheel is “locked” and will not spin (could still skid) but not spin.