[Mercedes.AMG]

Last week when reversing up my steep-ish ice covered drive my GLC with its 4WD system, it just sat there spinning its wheels, I have no idea what wheel or wheels that were spinning, but it did not move one little bit.

I eventually got up there with a run-up but I was wondering why the 4WD system was so completley useless?

I'm kinda hoping the perhaps its because the traction control systems may not fuction in reverese?

I would have expected the system to brake a spinning wheel, like it has on the VW and Audi's I have previously owned? including both Haldex and Torsen centre diff vehicles

Anyone know?

 

[ajmtbm]

Last week when reversing up my steep-ish ice covered drive my GLC with its 4WD system, it just sat there spinning its wheels, I have no idea what wheel or wheels that were spinning, but it did not move one little bit.

I eventually got up there with a run-up but I was wondering why the 4WD system was so completley useless?

I'm kinda hoping the perhaps its because the traction control systems may not fuction in reverese?

I would have expected the system to brake a spinning wheel, like it has on the VW and Audi's I have previously owned? including both Haldex and Torsen centre diff vehicles

Anyone know?

i thought the 4MATIC was permanently locked 60/40. Did you see any traction control lights or anything come up that indicated something abnormal?

 

[Mercedes.AMG]

No lights, just spinning wheels, I believe the rear wheels must have been spinning as the fronts were on the road that was not icy.

 

[Toobad]

If 4MATIC is working correctly I would have thought there would be no evidence of wheelspin. Under normal driving conditions front/rear torque is split 40/60 on AMG models and 45/55 on the rest of the range. Wheel slip is detected by the Electronic Traction System (4-ETS) which monitors the wheel speed sensors used for the Antilock Braking System (ABS) and the Electronic Stability Program (ESP). Wheel slip can be detected in milliseconds and 4-ETS will pulse the brakes to control rotation and cause torque to be diverted to the remaining gripping wheels. It will proportion torque accordingly right down to only having one wheel gripping.

My own experience in the snow and ice could not have been more different to yours. I too have a very steep driveway entrance but found I could get up or down with no drama whatsoever in deep snow or pack ice. I suspect the secret was in the speed. Admittedly I have the benefit of Downhill Speed Regulation and Slippery Mode which comes with the Off-road Engineering Package but I found an ascent speed of 2-4 mph allowed Red Ken to consistently drag himself up the slope without any fuss at all. Here's a link to some pics of my driveway entrance in another thread:

Driveway at Castle Toobad

 

[Philamg]

The split on the AMG43 is 69/31

 

[Toobad]

Whoops, my bad! Of course it is because it is more of a driver's car and will have more rear bias. At least I remembered there was a difference but, TBH, these days getting my own name right is considered a triumph

 

[Mercedes.AMG]

Don't matter what it is, if your in reverse :surprise: