Automatic transmission in snow

Manual mode and jake off or on low at the most if your loaded heavy. I took an auto dt12 up to rochester ny 2 weeks ago during the snow storm with only 7k in the box and did just fine, little hairy at times but got there and back just fine.

 

I have 500000 miles on a DD15 with Mercedes 12 auto driven every hill on 80 from coast to coast
use jake all the time sparingly in bad conditions
and never put it in manual
but maybe I don't know what I am doing

 

Those scare me in auto in bad conditions. I've only been driving less than 2 years but the dd15 and the auto with the jake on high would be an accident waiting to happen in some spots. I hardly use the jake in bad conditions and just take it at a safe speed with the power divider kicked in

 

I would assume you would use manual mode in slippery conditions? Holding a gear at 20mph is better than it attempting to shift at a bad moment.

 

My exp. is with Mack's and either Eaton Fuller Autoshift or Mack Mdrive automatic transmission, gentle on the throttle, jakes on low or off, increase following distance, and take your time. I run I-70 and the Mtn's of Colorado with mine, almost 1.5 million miles on autoshifts, almost 200K on automatics.

Manual mode is beneficial, but not always required, most of the time I run mine in auto mode and just play with the throttle, Manual mode on the down hill. Only time I use manual mode on the climb is very low traction situations where even with chains I start to spin.

 

With the auto in auto I would never use the jakes. Those #### things love to downshift and hit 1800 rpm or more just for kicks and stopping power. In manual it might be ok if you know your truck and are confident in your traction, but in auto I'd think it'd be a bit too much of a crap shoot unless you REALLY know your trans and it's shift points.