OldSmokey

Has anyone disconnected their front drive line to help improve mileage? Im going to be making some fairly long trips and was wondering if this would help any? Anyone have any input. Thanks Joel

dieselengineer

Without going with free spinning hubs, not much gain. You will be still spinning all the drive train in the axle. With the free spin hub mod, all the drag of the drive train is removed and you only get a small gain (1 mpg). You will gain more by just inflating the front tires to 80 psi.

Deesil

you'd have to drive a LOT of miles to make hubs worth it LOL

lemme see, let's say it cost you $1,500 to put in free hubs @ $2.90/gal while you gain 2 mpg by doing it.

you can buy 517 gal with $1,500 @ $2.90/gal

.....which will take you 9,300 miles @ 18 miles/gal

it costs you 16.1 cents per mile @ 18 miles/gal @ $2.90/gal
.....14.5 cents per mile @ 20 miles/gal @ $2.90/gal ....for a grand savings of 1.6 cents per mile
$1,500 / .016 = 93,750 miles to break even (if it costs 1500 bucks...I think they may be higher)

If you only got 1 mpg better...well....double that. I seriously doubt you'd see 2 mpg difference, but what do I know

to put it another way....instead of spending the loot on the hubs.....it will buy you almost 10k miles of fuel

(sorry I got a little bored )

OOPS

MPG is not the only thing you will gain from freewheeling hubs, there is a whole heck of a lot less wear on the front-end components like u-joints in the axles and D-shaft.

annabelle

I don't believe the transfer case will lube w/o the front drive shaft turning.

Deesil

It's also debatable how much wear and tear you'd save with freewheeling hubs. I've had 4x4's with lockout hubs and I gotta tell ya, I had to replace U-joints in them around the 100k mile mark too. To each his own tho...I really like the fact that I can put my truck in 4H just by pulling back the lever. Of course auto-locking hubs would do that too. So I'll just shut up now

jamesbfishin

The lockout hubs will the cause lack of lubrication in the transfer case? That's something to consider as I was possibly going with lockouts.

dieselfan

i love when members do stuff like this, i m too lazy.
thanks

dieselengineer

Also you need to add the replacement cost of the stock hubs. If you tow, you are going to wear out a set or two in the 93,000 miles. The stock hubs are real light duty, and are nonserviceable. It will only take a set of hubs to pay for the up grade then you figure that the tow from out in no where will be big $$. When the stock hubs go, it only takes a few miles without warning.

OldSmokey

So disconnecting the front drive shaft wont do much for milage?

Jeff K

There is plenty of lubrication in the transfer case for the parts that are moving. The only parts that are not being lubricated are the chain and front driveshaft sprocket, and if they are not turning...no problem.

The entire front differential is still turning, causing drag. The front driveshaft out of the system won't change that.