Driving in 2wd with hubs locked

[TechTonics]

Hi all. I just purchased a 2001 E250 SMB. 5.4L EB. 175,000 miles

The 4x4 conversion was done by agile.

The seller told me it’s not recommended to drive on dry pavement in 4x4.

If I’m driving in mountains where it’s snow packed in some places and dry in others, is it ok to leave the hubs locked and toggle back and forth between 2wd and 4wd?

I have a buddy with a quigley, and he leaves his hubs locked for months at a time, even if he’s just driving in 2wd.

Otherwise, is it ok to drive on dry pavement in 4x4 mode for short periods?

What do you guys do?

Thanks. This will be the first question I have of what will certainly be MANY, so get used to seeing me around!

[simplesez]

I leave my hubs locked all winter. It doesn't hurt anything. I grease the front hubs every year or two.

[boywonder]

Won't hurt anything.....

Upsides:

In the snow/offroad etc no getting out of the vehicle to use 4WD

Downsides:

You are spinning more stuff (front axles/driveshaft) so your rolling resistance goes up a smidgen and your gas mileage goes down a little.....and maybe slightly increased maintenance...fairly insignificant.



Also, you can use 4WD on dry pavement if your front and rear differentials are open or limited slip. If you engage a locker on either end, you'll quickly figure out that it's tough to drive on dry pavement.

[TechTonics]

I drove it this morning in 4x4 mode. Only slow on residential streets. Didn’t pull or yank at all. Steered fine.

I had an old Isuzu Trooper in the 90’s that would pull all over the place in 4wd on pavement. This felt pretty good.

Solid, actually.

[TechTonics]

Originally Posted by boywonder

Also, you can use 4WD on dry pavement if your front and rear differentials are open or limited slip. If you engage a locker on either end, you'll quickly figure out that it's tough to drive on dry pavement.

Can you expand on that a little more? Explain it to me like I’m a child.

It has push button 4x4 and 4Lo

I don’t even know if it has a locking differential. Agile did the conversion

[boywonder]

Originally Posted by TechTonics

.... Explain it to me like I’m a child.

I don’t even know if it has a locking differential. Agile did the conversion

With an "open" differential (the big pumpkin on each axle) only one wheel drives the vehicle down the road at any given moment for each axle.

A limited slip differential has clutches inside that allow the opposite wheel to help drive the vehicle if the driving wheel starts to slip/lose traction.

A differential with a "locker" feature allows the differential to have both wheels driving the vehicle when the locker is engaged. This feature is only used when off-road or other conditions where you need both wheels driving on one axle.

When you go around a corner the outer wheels have to spin more times than the inside wheels..since the arc they track is longer.....this is impossible with a locker engaged, so the tires make all kinds of slipping/skidding noises on dry pavement with a locker engaged.

If your van has a locking differential there would be another button for that, and the fact that it drives at least as good as your trooper (we used to have one of those) means the diffs are either open or limited slip, which is the most common setup.

Technically, with "open" differentials in 2WD the vehicle has one wheel pushing the vehicle down the road, and in 4WD you've got 2 wheels driving, one on each axle. Limited slip helps if the driving wheel starts to spin.

In my van my front diff is open and the rear is limited slip, pretty typical for these vans. There is an axle code on the Mfr data plate inside the driver's doorwell....if you post that here one of the smart forum members can tell you if the rear is LS. Your front is likely an open differential.

[deserteagle56]

Originally Posted by boywonder

Also, you can use 4WD on dry pavement if your front and rear differentials are open or limited slip.

NOT!

I've owned a lot of 4x4 vehicles in my day; the owner's manuals on each and every one specifically warn against using 4x4 on dry pavement. The only exception is if it is an AWD vehicle which has a type of differential in the transfer case to allow differing speeds front and rear. This has nothing to do with whether your front and rear diffs are open, limited slip, or locking. And yes, you should not have a diff locked on dry pavement either.

As far as leaving the front hubs locked in...Ford is the only manufacturer that provides free-wheeling hubs on the front axles (for which I thank them!). Check out any older heavy duty Dodge/Ram - they don't have the hubs (newer ones have an "axle disconnect", not the same as hubs). So all that stuff in the front axle is turning needlessly all the time whether you need it or not, costing you mileage and wearing out parts. I have one of those older Dodges and have installed a conversion unit so that it too now has locking hubs. 95% of the time I don't need the front end components turning so the hubs are unlocked. My dad, on the other hand, locked his hubs in November and unlocked them in April (lived in snow country). So no, leaving your hubs locked in is not a problem.

[Orv]

The problem with 4WD on dry pavement is there's no *center* diff, like a full-time AWD vehicle has. When you turn corners the front and rear axles travel different distances and you get binding that can put tremendous stress on the drivetrain. On loose or slick surfaces the tires can scuff a little to make up the difference.

[Jeffrey]

I wouldn't do it for the reasons stated, and my vast personal experience.

[TechTonics]

Thanks all. Especially @boywonder. Great synopsis.

I don’t plan on driving in 4wd on dry pavement. It was mostly to confirm that the 4x4 system was engaging when taking it for a pre-purchase test drive (on dry roads).

The van has a limited slip rear differential. It was even in the sellers description of the vehicle, but I must’ve missed it the first 3,000 times I read the listing.

Thanks again, everyone