Winter questions for noob owner

[tron67j]

I agree, love my truck and all that comes with it. I don't have nearly the snow I used to drive in, and don't miss it at all. Last year .6 inches. Had to run the snowblower in the yard for a couple hours to run the gas out that I had put in it at the beginning of winter. My goal is to eventually live somewhere that does not have a word in the native language for snow.

 

[imcoldhere]

Not picking on you in particular but I see this mentioned a lot and I don't have first hand ownership experience with the auto transfer case in Ram 1500's specifically - but I do have extensive first hand experience with other applications of BW's TOD system and other auto-4WD on vehicles (Isuzu, Jeep, Ford) and on all of those it is programmed to engage the aux secondary axle briefly on any launch because it can't know whether it's on a slippery surface until slip occurs, so it hedges the bets by just starting off in 4wd from every stop and from any application of additional throttle at higher speeds. You can even watch the little TOD engagement indicators light up on Isuzu's dashboard to illustrate how much it's engaging the front axle - which it will do even if you're going 50mph and mash the pedal. On my Jeep which is natively front wheel drive with an auto-4wd engagement of the rear axle it does the same thing and with JSCAN software on a phone I can watch it display % engagement in real time, it always pulses the clutch when throttle is applied from a stop or while under way.

What I'm getting at here is that other applications of this auto-4wd scheme are proactive with engaging the second axle, are we sure that the Ram application is not?

On WJ's with Quadra-Drive the front axle engagement is mechanical and completely reactive so on those it really is necessary to slip first before the front axle comes in. But that's because it needs a difference in driveshaft speed to pump oil behind the clutch engage piston... that's a world of difference from electronic control.

I wasn’t going off personal experience but from the fact that on highway 4x4 auto puts it into 2wd when cruising down the highway and that I had a coworker have this happen to him. He was going up a hill in our area in auto and decided to pass a slow driver in the slow lane, he went to move into the next lane and truck saw slippage as his rear end was sliding out and locked 4x4 and put him in the ditch in between the 2 highways. So partially due to that knowledge and partially to others I would rather just not use the auto mode but this is all personal preference so to each their own

 

[Tim7139]

It is only necessary to apply brake pressure to the free wheel which then brings the cam ramps into play, the LSD does its job and presumably you continue on your way....

This process is not instantaneous. The BLD brake application period is typically not long enough to meaningfully complete the process, so it restarted every time BLD applies the brake and does not complete - hence the guidance from the owners manual.

It's possible for FCA to extend the duration of the BLD brake activation period to avoid this, and they may have done so in one or more of the TRX drive modes, however the cons of doing so likely greatly outweigh any benefit of doing so for normal driving.

 

[Tim7139]

I wasn’t going off personal experience but from the fact that on highway 4x4 auto puts it into 2wd when cruising down the highway and that I had a coworker have this happen to him. He was going up a hill in our area in auto and decided to pass a slow driver in the slow lane, he went to move into the next lane and truck saw slippage as his rear end was sliding out and locked 4x4 and put him in the ditch in between the 2 highways. So partially due to that knowledge and partially to others I would rather just not use the auto mode but this is all personal preference so to each their own

Hope he was not alright.

With either transfer case in any 4wd mode in these trucks if you stomp on it enough to break traction you'll normally feel the rear end fish tail, so on it's own that is not an indication of 4wd not being engaged when his rear wheels were slipping.

I'm a big proponent of finding an area to get a feel for what your vehicle will do when it's slick, local law enforcement not so much ;-).

 

[ramffml]

I wasn’t going off personal experience but from the fact that on highway 4x4 auto puts it into 2wd when cruising down the highway and that I had a coworker have this happen to him. He was going up a hill in our area in auto and decided to pass a slow driver in the slow lane, he went to move into the next lane and truck saw slippage as his rear end was sliding out and locked 4x4 and put him in the ditch in between the 2 highways. So partially due to that knowledge and partially to others I would rather just not use the auto mode but this is all personal preference so to each their own

I'm not going to deny it may have happened to your buddy. But just keep in mind, 4x4 auto modes (glorified AWD) are around in literally everything for many decades now. The Jeep GC for example, I don't know how many of these things are running around but in Canada they are all each and every one 4x4 auto, not a single 2wd is sold here (FCA doesn't ship them up, not an option). Auto mode is completely safe or else there would be lawsuits and recalls and horror stories everywhere.

 

[LouM]

In low speed, light throttle applications the auto transfer case is a piece of garbage.
You can not gently walk the truck thru a slick spot.
When you place your truck in Park it disengages the front axle even in 4 wheel lock.
It will not provide 4 wheel engine braking going down hill on ice.
I have personally had my truck slide backwards in rear wheel drive only while in 4 loc and park.
It will not power the front axle when you try and gently walk it up an icey hill till the rear is slipping then you are done for.
The same on wet grass going up a hill or trying to back up the rear has to slip before it brings in the front axle.