Front Diff Locking Hubs

when he has the hubs locked even if in 2WD the diff centre axles tail shaft etc are all being turned over by the rolling of the wheel. Doing this all the time will wear components and make steering heavier due to the fact that the CV's are engaged inside the housing.
As a general thing for most highway driving I leave the hubs unlocked and when i start getting to the rough stuff I stop and lock them in case I need to engage. There is nothing worse than waiting till your stuck before wading throug water or mud to engage hubs.
Once a month if I havent been using 4WD i engage the hubs in 2WD for a 30-50km trip to town. This gets all the diff components ets turning over and lubricates everything. Personally I wouldnt leave em locked all the time. Hope this helps your grandson.

Trekkie

Never on bitumen, as you will "wind up the axles", and they will just snap like carrots.

Always on greasy dirt roads, as it is safer, and I keep the speed down.

I run 4x4 mode on corrugated outback roads, firstly it gives me more control, and secondly I do not want to run the chance of getting flat spots on bearings, and gears, by not having anything turning.

I use low range a lot on rough outback roads, firstly as I have to , and secondly it gives me the control I need.

In saying that there were a lot of sections of the Canning Stock Route, I didn't need to use 4x4 hi, or low range, but I chose to do so to give me control of the vehicle, and of course the "what if" factor.

Cheers
Bucky

Trekkie the correct term is Free Wheeling hubs (not diff locking hubs) & despite what Bucky is saying can be left in on any surface. There is barely any noticable difference in the steering or handling of the vehicle in 2wd. Really they are there to save a little fuel (1 to 2 mpg) and minimise wear on the front axle assembley when 4 wheel drive is not required.
When to lock: Ideally lock them well before you get into an offroad situation that way the diff oil will have warmed up & you can slip it into 4x4 at a seconds notice without getting out of the car (in the mud). If the car is not being used in 4x4 for an extended period put the hubs in & out occationally to lubricate the diff & avoid wearing a flat spot on the front slip joint. It also stops the freewheeling hub it's-self from siezing up from lack of use.
When not to lock: When you want to save fuel.
Can you damage them: While not specifically damage from leaving them in, moisture getting past the seals can rust the hubs & sieze them. Have heard of the splines shearing when abused but not normally an issue.
Most of our 4x4 utes at work have the front hubs engaged around Easter & taken out in November purely for convienience.

Slightly off topic but there is actually a device that could be called a Diff Lock hub on early model Landrovers where a bolt protruding from the axle assembley could be wound up manually to lock solid the rear diff. Not quite as convienient as an air locker but for it's time very handy.

Cheers Craig............................

The term "diff locking hubs" is a little confusing. If you mean diff locks, they should only be used when your vehicle needs extra traction, in the extreme. If you mean free wheeling hubs, (which you lock by turning the device on the wheel hubs), then there is no problem leaving them locked permanently, except that you will use slightly more fuel. Hope this helps.

Happy trails, Mike.

Hi Trekkie,
They are correctly known as free wheeling hubs AFAIK.
I have spent much time in the past talking this issue through with my mechanic. I have been running my hubs "locked" for years, (in my GQ Patrol,) and can tell you there is no noticeable difference in fuel economy, no difference in noise, no difference in handling, no difference in wear and tear either. I do it because I had been caught out engaging low range on a creek crossing and having to struggle across because my wife had unlocked the hubs earlier, thinking she was doing the right thing, and, me not knowing, dropped it into low range with the unlocked hubs. So now we have them locked always, so we can hit low range whenever!
Just DON'T drive in 4WD (high or low range) on a hard surface! If the "little" stick is in 2WD, but the hubs are in, that is OK.

Cheers

Brian