[zim]

I have used my 4wd high in the rain all the time with speeds in excess of 60 mph as traction is a problem in 2wd. No issues.

So remind me again as to why you would buy a vehicle with 4wd, and not use it in the rain, or snow or when traction is a concern wether on the highway or off road ?

 

[troverman]

I have used my 4wd high in the rain all the time with speeds in excess of 60 mph as traction is a problem in 2wd. No issues.

So remind me again as to why you would buy a vehicle with 4wd, and not use it in the rain, or snow or when traction is a concern wether on the highway or off road ?

Sure. Part time 4x4 requires at least one wheel being able to "slip" in order to not break something in the driveline. On snow-covered conditions, this slip is generally imperceptible because snow is low traction and getting a wheel to slip is not that hard. Try to make a sharp turn on dry pavement with 4x4 engaged, and the steering wheel will be tugging and you'll abruptly hear a tire chirp like you've just burned rubber...because you did...and the truck will generally just buck and resist the turn. You could get away with this for awhile, but eventually something will break.

Rain lowers traction on pavement only slightly. I've never understood why people think 4x4 helps them in rain. 4x4 should be engaged when you are constantly spinning your tires during normal driving...for example, cannot make it up a snow covered hill or you spin just taking off from a traffic light. In this case, 4x4 helps by adding at least one additionally powered tire. So unless you are spinning out trying to make it up a hill or when taking off from a stop light, you are not losing enough traction to warrant 4x4 use. That does not include goosing the throttle to try and cause the wheels to spin. If your tires cannot easily spin in the rain, using 4x4 serves only to help prematurely wear out your drivetrain and use more fuel and create more understeer. If the vehicle is hydroplaning, 4x4 does not help.

Manufacturers make their transfer cases rugged, and they can take this kind of abuse for awhile...but eventually something will break.

Snow is a similar story...what I call "changing conditions." If you drive along and sometimes the road is snow covered and sometimes it is dry, running 4x4 on the dry sections is very hard on your driveline.

Last comment: if you never turn and only go straight, you can use 4x4 on dry pavement and never harm a thing. It's only the turns which cause the difference in wheel speeds to force a wheel to need to slip .

 

[BagMan]

It's too bad we can't set which axle is driven when in 2WD. Nothing worse than a lightly-loaded rear end tying to push these big cabs and motors instead of pulling.

 

[troverman]

It's too bad we can't set which axle is driven when in 2WD. Nothing worse than a lightly-loaded rear end tying to push these big cabs and motors instead of pulling.

Theoretically, you can! Just remove the rear driveshaft and then engage 4x4. You are now driving a front-wheel drive pickup and will experience no axle binding.

The problem is that the rear diff and driveshaft are much larger and more heavy duty than the front one, because in 2WD they must shoulder all of the truck's torque. But when 4x4 is engaged and the front is driven, it never has to deal with more than half the load. So prolonged driving in just front drive mode, or if any towing was done, would quickly cause problems with the transfer case, front driveshaft, front diff, and front axle components.

I find crew-cab half ton trucks don't quite have the weight bias problems that old trucks did. Modern engines tend to be lighter than the old engines (a 5.7L Hemi was "small" compared to a lot of truck engines from the 1970's and 1980's). Modern trucks have shorter pickup beds and longer cabs than ever before. I'm actually pleasantly surprised how well a modern crew half-ton will go in snow even in 2WD. That said, HD trucks seem to go worse, even in crew cab form. Could be the longer beds, the higher tire pressures, or the heavier engines up front.

 

[Red Pilled Rebel]

I have a 2016 and the roads are icy outside. So should I put it in 4LOCK and just drive slowly? I’ll be on city streets as I live in downtown Dallas

 

[Bluefive5]

With my 2017 Rebel and living in Arizona I utilize 4WD in just 3 scenarios:

1. Pulling my boat out on a slippery boat ramp.
2. Driving uphill on a paved road with 4 or more inches of snow on the road.
3. When off road in the sand or loose rocks (only while climbing an incline greater than 30 degrees).

At all other times when some might be tempted to switch out of 2WD, I find it safer and more efficient to just reduce speed. Of course there are random occasions when I'm in the desert or forest and I accidently get stuck in loose soil and my tires start spinning. That is when I'm the happiest knowing I have a 4x4 Rebel.