Interesting article on free wheel hubs. There are two opposing camps about free wheel hubs, and never the twain shall meet. After many years driving a Willy’s jeep with permenantly locked hubs, I’ve never had a single problem with the front axles, or with mileage, loss of power etc.
bq.. Why would you want to do this and why do some vehicle manufacturers fit them as standard? In theory, when you have the hubs in the free position and the vehicle in 2wd, it takes less force to move the vehicle over the ground. This is because the front wheels are only being pushed around and not the rest of the front half of the drive train. Also, in theory, you are supposed to get less tyre wear because you are decreasing the drag on the front wheels and decreased wear on the moving parts in the front drive train.
In practice then, through my experience, it doesn’t really make a lot of difference. In fact, if you read through the manufacturer’s handbook they will tell you to engage it to the lock position and drive the vehicle around. This should be done every month to ensure adequate splash lubrication to the moving parts to ensure that they do not wear out prematurely!
There is a difference in fuel consumption but it is negligible especially with a diesel engine. On a trip, say from Kampala to Nairobi (650kms), you might save in the region of about 5-10 litres. As to the wear and tear aspect, I’ve seen more damage caused by vehicles run in the free position than to the same model vehicle with the hubs permanently locked!
>> ‘Free Wheeling Hubs: Why Have Them?’:http://www.oncourse4wd.com/4wd/4wd_free_wheeling_hubs.asp