Driving in 4WD High

[yooperdave]

How fast (with duration) is it acceptable to drive in 4wd high while driving?

I catch myself going 55-60 sometimes on partially snow covered roads for many miles at a time.

I do not want to hurt the truck, and wanted some guidance.

TIA

Yooper Dave

 

[George2615]

I don't see a problem driving at speed in 4WD on snow covered roads. When driving on clear paved roads at speed there is no need for 4WD so take it out of 4WD. Driving on clear paved roads in 4WD does cause extra wear and tear on 4WD moving parts. Most owners manuals tell you not to use 4WD on dry roads. When on dry roads in 4WD and you try to make a sharp turn you will feel the front tires try to skip. This puts excess stress on the drive axles and joints. I only use 2WD unless road conditions require 4WD use or if I feel the tires starting to break loose. Several previous trucks I've owned had manually locked hubs. In winter I would leave the hubs locked in but have the transfer case in 2 WD then if I needed 4WD I just pulled the lever into 4WD either at a stop or when coasting. My truck now has automatic hubs and electronic switching for 4WD.

 

[JDeerekid]

I second what George said. I dont usually run in 4wd unless it is needed anyway but have driven many miles with it engaged when it was needed with no problem.

 

[framer]

To fast for me 40 to 50 mph. My speed.Dont think it hurts drive line to go faster. Framer

 

[dgl24087]

I believe my Owner's manual for my Ram 1500 says max speed should be 55 in 4wd.

 

[RonMar]

Speed shouldn't be a problem. With manual hubs, all those drivetrain parts spin that fast when you just have the hubs locked in. I have never seen a speed restriction in any operators manual I have looked at That is why running with the hubs locked in costs you some extra fuel. You are spinning all those extra parts via the front wheels.

AWD vehicles also have all the parts spinning all the time at highway speed without issue. The problem is as already mentioned. A regular 4X4 has no differental between front and rear axles. A hard dry surface that dosn't allow some wheel slip will cause a binding in the drivetrain that can result in severe gearbox/transfer case damage. AWD drivetrains get around this problem by adding another differential or a slip clutch mechanism between the front and rear axles to relieve this stress. This is the same as the axle differential relieves the stress of the outside wheel wanting to turn faster than the inside wheel when going around a corner.

 

[Inkomodius]

What make model and year is your truck?

 

[WH401]

Recently we had enough snow here to cover the roads with about 3 inches and I drove the 92' in 4 High at about 40 - 50 without any problems. Definitely don't drive it in 4 high when the roads are dry though, you'll cause damage.

The 06 has automatic locking hubs so all the front drive line parts are always turning constantly when going down the road, no matter whether your in 4 wheel or not. I plan to put manual locking hubs on it in the future to cut down on fuel usage and drive line wear, worst thing they ever did was get rid of them from the factory.

 

[farmboy12]

WH401-
Where are you at in So. MD to get that much snow?! Most we've had at all this year was maybe 1-1/2". Only 3-4 snowfalls!


Kyle

 

[WH401]

WH401-
Where are you at in So. MD to get that much snow?! Most we've had at all this year was maybe 1-1/2". Only 3-4 snowfalls!


Kyle

It was that storm on the 21st of January, it gave La Plata about 3 - 3.5 inches. The storm ended up going father south than the weathermen first expected so we got more snow then most. County wasn't prepared at all and hadn't done anything to the roads, with no salt they were quickly covered up with accumulation. There were numerous school bus and automobile accidents that morning. The county ended up closing schools early that day and schools were again closed the next day.