5thGenRams Forums

Register a free account today to become a member! Once signed in, you'll be able to participate on this site by adding your own topics and posts, as well as connect with other members through your own private inbox!

  • We have been battling an on and off issue with registration verification emails not being sent out with certain users. We have finally got the issue resolved so if you have tried registering for the site but have not received a verification email, just request another verification email when you log in and you should now receive it. If you still don't receive the verification email, send us an email at [email protected] and we will get it resolved for you. Thanks!

4 Auto on Pavement?

VictorLin0725

Active Member
Joined
Nov 20, 2018
Messages
41
Reaction score
7
Does anyone know the difference between 4 auto and 4 high? This question might have been answered elsewhere but I'm still a little confused. Is 4 Auto just a seamless switch between 2wd and 4 high or is it a completely different system like AWD? From what I gather you cannot drive in 4 high on pavement/highway when there is rain or light snow because of power distribution issues...so I'm not sure when I would use 4 Auto.
 

SpeedyV

Ram Connoisseur
Staff member
Site Supporter
Joined
May 6, 2018
Messages
4,754
Reaction score
4,409
Location
Fort Worth, Texas
Does anyone know the difference between 4 auto and 4 high? This question might have been answered elsewhere but I'm still a little confused. Is 4 Auto just a seamless switch between 2wd and 4 high or is it a completely different system like AWD? From what I gather you cannot drive in 4 high on pavement/highway when there is rain or light snow because of power distribution issues...so I'm not sure when I would use 4 Auto.
The "seamless switch" comment is most correct. You would never run 4 HI on pavement, but 4 AUTO is fine, as the system is detecting slippage and only engaging 4WD when necessary. You'll just lose a bit of fuel economy when running 4 AUTO vs. 2WD. Most folks use 4 AUTO in inclement weather and 4 HI (i.e. full-time 4WD) only in off road or heavy slippage (boat ramps, heavy snow/ice, etc.) conditions.
 

GATORB8

Well-Known Member
Joined
Oct 17, 2018
Messages
349
Reaction score
262
Location
Charlotte, NC
4Auto locks the front hubs and shifts the T-case into 4Hi when it senses slippage. I wouldn't run 4Auto full time, but it's good for inclement weather or off road.

From the manual:
This electronically shifted transfer case is designed to be
driven in the two–wheel drive position (2WD) or fourwheel
drive position (4WD AUTO) for normal street and
highway conditions on dry hard surfaced roads). Driving
the vehicle in 2WD will have greater fuel economy benefits
as the front axle is not engaged in 2WD.
For variable driving conditions, the 4WD AUTO mode can
be used. In this mode, the front axle is engaged, but the
vehicle’s power is sent to the rear wheels. Four-wheel drive
will be automatically engaged when the vehicle senses a
loss of traction. Because the front axle is engaged, this
mode will result in lower fuel economy than the 2WD
mode.
 

VictorLin0725

Active Member
Joined
Nov 20, 2018
Messages
41
Reaction score
7
The "seamless switch" comment is most correct. You would never run 4 HI on pavement, but 4 AUTO is fine, as the system is detecting slippage and only engaging 4WD when necessary. You'll just lose a bit of fuel economy when running 4 AUTO vs. 2WD. Most folks use 4 AUTO in inclement weather and 4 HI (i.e. full-time 4WD) only in off road or heavy slippage (boat ramps, heavy snow/ice, etc.) conditions.
4Auto locks the front hubs and shifts the T-case into 4Hi when it senses slippage. I wouldn't run 4Auto full time, but it's good for inclement weather or off road.

From the manual:
This electronically shifted transfer case is designed to be
driven in the two–wheel drive position (2WD) or fourwheel
drive position (4WD AUTO) for normal street and
highway conditions on dry hard surfaced roads). Driving
the vehicle in 2WD will have greater fuel economy benefits
as the front axle is not engaged in 2WD.
For variable driving conditions, the 4WD AUTO mode can
be used. In this mode, the front axle is engaged, but the
vehicle’s power is sent to the rear wheels. Four-wheel drive
will be automatically engaged when the vehicle senses a
loss of traction. Because the front axle is engaged, this
mode will result in lower fuel economy than the 2WD
mode.

Thanks guys that clears it up!
 

Neurobit

RAM Sorcerer
Joined
Jul 9, 2018
Messages
5,161
Reaction score
3,935
Location
Texas
4Auto locks the front hubs and shifts the T-case into 4Hi when it senses slippage. I wouldn't run 4Auto full time, but it's good for inclement weather or off road.

From the manual:
This electronically shifted transfer case is designed to be
driven in the two–wheel drive position (2WD) or fourwheel
drive position (4WD AUTO) for normal street and
highway conditions on dry hard surfaced roads). Driving
the vehicle in 2WD will have greater fuel economy benefits
as the front axle is not engaged in 2WD.
For variable driving conditions, the 4WD AUTO mode can
be used. In this mode, the front axle is engaged, but the
vehicle’s power is sent to the rear wheels. Four-wheel drive
will be automatically engaged when the vehicle senses a
loss of traction. Because the front axle is engaged, this
mode will result in lower fuel economy than the 2WD
mode.
Yep. Nailed it.
I did run it in 4WD Auto the first week I had the truck, on dry pavement. No issues whatsoever, so it will def not hurt anything except MPG.
 

Users who are viewing this thread

Top