Can you switch into 4wd on the fly at ANY speed? Or is it limited?

I have heard several times that you shouldn't drive in 4wd on hard, dry pavement. Is this true? What damage can ensue?

 

You should be able to switch on the fly at or below 45mph to 4WD High. Low range is done stoped in nuetral. As for dry hard surface why would you want to drive in 4WD in those conditons for any preiod of time anyway?

 

I thought it was OK upto speeds of 55 or 60 to shift on the fly. My only (very minor) complaint with my Screw is the the **** for the 4x4 is too close to the AC controls. I would have liked it to be harder to move the switch into 4x4. Maybe a pull and twist type switch. In 6200 miles I have only turned the wrong on once, but that was enough.

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2001 Supercrew XLT 4x4, 5.4, tow pkg, limited slip, skid plates, 6 disk, keyless entry. Deepwedgewood blue ext. Dark graphite int.

 

MtnMike -- I wouldn't. Here's the deal. My dealer made a dealer-trade for my dream Screw. I have reason to believe that the kid who went and got it drove it many of the 200 miles back in 4wd high. On dry highway surfaces. On my test drive he had me switch it into 4hi at 70 mph (I protested, but he was certain it's no problem). He explained that he thought the truck handled better in 4hi. Now unless I'm mistaken, only newer systems, designated "AWD" or "Fulltime 4wd" or something similar, are designed for use on long, dry, pavement trips. So I'm wondering if this trip mis-treated this truck, and if so, what are the likely results?

 

From what I understand, axle-wind up can occur, not to mention shortening the life of the tires. If it doesn't have any apparent driveability problems, then I would think things are OK. If something happened to the axles or transfer case, I think you'd be able to feel it.

I switch to 4Hi when I'm below 60mph when I come to a stop light in the rain, or anytime it starts to rain.

 

Okay I pulled my trusty Ford F-150 S-Crew owner's manual and turned to pages 168 and 169 which state the following:

"Shifting from 2H (2WD high)to 4H (4WD high)"
"Move the 4WD control to the 4H at a stop or up to 55 mph (88kmph). At tempatures below 32F (0 C), shifts from 2H to 4H should not be performed above 45mph (72KMPH)" "DO NOT SHIFT INTO 4H WITH THE REAR WHEELS SLIPPING!'

"Shifting from 4H (4WD high)to 2H (2WD high)"
"Move 4WD control to 2H at any speed."

"Shifting between 4H(4WD high)and 4L(4WD low)" Vehicle must be stopped; Brake on; Gearshift in nuetral; then shift from 4H to 4L.

4WD OPERATIONN IS NOT RECOMMENDED ON DRY PAVEMENT. DOING SO COULD RESULT IN DIFFICULT DISENGAGEMENT OF THE TRANSFER CASE, INCREASED TIRE WEAR, AND DECREASED FUEL ECONOMY!

I hope this helps



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Mtn Mike

 

Thands. That explains that the front tires already look oddly-wearing. Any more input is also welcome.

 

LongTime,

you may want to take your truck into the dealer for a alignment check. My front tires started getting that funny wavy look on the edges right away. Took it to the dealer and had them rotate the front tires to the back and align the front end. Now they appear to be wearing evenly after 10k miles. My truck didn't "feel" out of alignment but the dealer assured me that it was.


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2001 Supercrew XLT 4x4.
Superchipped 5.4L, 3:55ls, tow package, heavy-duty electrical and cooling, skid plates, 17" 10 spoke wheels, remote keyless entry, cabin air-filtration kit, moonroof, bed extender, "Ford" rubber bed mat, rear slider, dark graphite int. and bright red exterior, SnugLid hard tonneau.
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