Hubs.

How do the 4wd front hubs work on these 04 PSD's?

I seem to understand they are vacuum operated, ESOF (Electronic Shift on the Fly) models....which is fine.... I'm assuming the dash switch selects 4wd and engages the hubs when you want them..

So riddle me this!

Why do the hubs have lock and unlock positions on them?

Should one in fact select unlocked for normal Hwy driving etc - and only engage the hubs when theres a chance you might need them for offroading?

Am I needlessly spinning front CV and front prop shafts while highway driving in 2wd if the hubs are set to locked?

Cheers!

 

Not sure about the 04 models but my 01 shift on the fly hubs have lock and auto. If I know I will be using 4wd I lock the hubs manually so I am sure they are locked and stay that way. For normay every day use I leave them in auto.

 

On a ESOF truck the hubs have Lock and Auto. Lock being locked all the time and auto only locking when vacumn is applied on command from the ESOF dash switch.

If you have ESOF and the hubs read Lock and unlock I would assume that someone has replace the OEM autos with manuals.

Driving around in Lock wont damage any thing but will cost a few MPG's.

 

If you have ESOF, then the hub positions are "Lock" and "Auto", unless of course the hubs have been replaced with aftermarket units.

Auto simply leaves the hubs unlocked until the ESOF dash switch is selected, then the hubs are locked via vacuum. If you manually set the hubs to "Lock", then yes they are locked in regardless of the dash switch. However the dash switch also engages the transfer case, so just locking the hubs doesn't put you in 4wd, but the front shafts will be spinning and reduce your fuel mileage a bit.

The purpose of the "Lock" position is in case of vacuum system failure or leaks, and also it's better suited when you are putting more stress (ie more serious off-roading, or a hard launch at the drag strip).

For winter driving, my hubs are usually in the "Auto" position, and I use 4wd when there is quite a bit of snow on the ground. I use the "Lock" position when I'm offroading or drag racing.

 

Thanks guys,

I'll go shift em back to unlock or auto - whatever it reads...

My son just mentioned they were in lock position the other night while we were laying on the floor connecting the aux trans cooler!

They must a been like that since I bought it - a few months ago - lucklily I've only done like 1200 miles in that time!

Maybe thats why it steers like a pig!

Cheers!

 

I think that has more to do with the fact that the truck weighs nealy 8000 pounds.

 

Yeah maybe - but the cruiser I had was similar, with the hubs out the steering was light and responsive - with them in it was heavier and less responsive because of the gyro torque factor of spinning the cv's & front shafts and prop shaft resisting turning force!

You could feel it thru the wheel - the difference I mean!

I'm thinking this truck has felt heavey and unresponsive on the steering, since I bought it...it seems to sorta want to follow the ruts in the road rather than where you point it - and given the radial typre it oughtn't do that IMHO!

It just hasn't felt "good" to steer since I bought it - I find myself always fighting the wheel and REALLY having to concentrate to hold a reasonable road position - whereas the cruiser would lope along with two fingers on the wheel all day - you never had to pohysically work to steer it!

It'll be interesting to see if this makes a difference in MPG and on road steering, now the hubs are shifted! I'll report when I've driven it again if theres a difference!!

One of the front spring hangers - looks to have had someone try and tow the vehicle out of a bog or something with a old hemp type rope at some point because theres a hunk a rope broken off and wedged pretty tight into the spring where it wraps around the spring hanger - maybe this too is affecting the steering..

Lets put it this way I'm far from happy with it!

Add to that whoever owned it before me musta been some kinda giant, because the foam in the outside bolster of the drivers seat, is sorta collapsed compared to the inside bolster so when I sit in the drivers seat I feel like I'm leaning out and if the door were to open I'd fall out!

Combine the leaning seat phenomenon with poor steering and the overall feeling driving this trruck is not far removed from driving a Cobb 'n Co Coach with horse team!

When I sit in the seat for an hour or more - I can feel the bar support frame under the right seat squab bolster, pressing up into the bone in my butt!

It gives me a crook back and pins and needles down to my acccelerator foot!

The cruise controls about the only relief for it!

I really do think Ford could learn lessons from the Japanese about ergonomics of layout and seating! Surely the components these days are all sourced from the same manufacturers?

Honestly - the plastic garden chairs out back are more comfortable than my Ford truck seats!

Maybe you get different level of fitout stateside...than we do in a XLT...what with capitans chairs and heated seats & mirrors etc...

We don't get such luxuries as block heaters and the rest - just not needed here!

Cheers!

 

Flywest a lot of the ESOF owners have eliminated the vacuum control lines to the hubs and capped them off because they sucked in whatever was outside to the inside of the hubs which subsequently ruined the very expensive wheel bearings.
Here in the States the whole units have to be replaced to the tune of $300.00 US aproximately. BARF.
I don't know what it would cost in your neighborhood, but going on what you paid for the truck, it cannot be any less expensive.
I recommend that you remove and cap the vacuum control lines from both of your hubs whether they are working or not. With your towing boats to the salt water, that has to be a consideration, vacuuming salt water into the hubs cannot be a good thing 400km from home!
Cap the lines going to the vacuum pump so that the ESOF and climate control still work for the transfer case and the air conditioning. All functions are run with a single vacuum pump.

 

That is probably a really good idea!

I can't think of any reason no to do that suggested mod.

I'm used to the idea of getting out to engage the hubs into 4wd if needed so I can't see that being a problem at any time!

I will look into that - you know it raises a really interesting question..

When I wanted vacuum over ride breaks installed - because suposedly there was no vacuum pump on a F 250 (the brakes don't use the vacuum - they have a nitrogen filled cyclinder) I had to pay $1200 for a USA Made "Thomas " brand vacuum pump to be installed underneath the vehicle to supply the vacuum for the brakes!

Now I find out there IS already a vacuum pump somewhere on the vehicle used to engage or disengage the front hubs?

I wonder why this pump could not have supplied the vacuum needed to operate the vacuum over ride brakes?

Nuthin but conundrums on this F truck.... the more I learn, the more I begin to wonder!

Tried to give you some rep for that but it says I have to spread it around first!

Cheers!

 

The vacuum pump for the ESOF and the climate control is much too small to provide the volume needed for brakes.
On our US models it's mounted on the starboard side of the engine compartment next to the vacuum reservoir.
I don't know where they would put it for RH drive vehicles because our climate control units are mounted right where your steering column goes.

 

I should take a good photo inside the engine bay for you guys so we can see whats different huh?

Hey I have another sort of related question if I may!

Some where I think I read about how the air con, could be 15 degrees cooler, if I bypassed something, because the cooled air is directed over a warm water heater core, before entering the cabin?

I can imagine warm air with the moisture removed by a air con would be a real assett for defrosting foggy windows in a cold climate, whereas here - heats our biggest issue!

On a hot day the air con flat out doesn't keep me cool to the point of getting cold like the land cruiser one does!

Obviously I should consider this modification most likely!
Anyone have the link to whats involved?
I'm all for being cold!

Cheers!