Auto Hubs

[Johny]

Can anyone help please? Having problems with one of the Auto Hubs on the driver’s side of my 1997 2.7TDi Maverick.

The hub keeps locking onto the axle when driving normally in 2wd. The occurrence is intermittent but frequent and tends to occur at lower speeds. I have stripped the hub down and greased it as per the download but I didn't take 'the inner sprung loaded locker' to pieces as it said this was unnecessary. I couldn't see anything obviously wrong or worn and can't understand what's causing the problem.
Could dismantling, cleaning and greasing the 'the inner sprung loaded locker' help and is this difficult to reassemble with it being spring loaded?

(I don't want to replace the hubs with manuals; my wife wouldn't appreciate it!)

Thanks


Johny

 

[Terranosaurus]

Try changing the oil in your transfer casing. If this has gone stiff and thick the drag may be causing the front prop to turn and thus the hub to engage.

 

[Johny]

Thanks for the advice. I'll have at look at this.

If this is causing the problem though why isn't it turning and locking the wheels at both sides. It only ever occurs at the drivers side?

Thanks again.

Johny

 

[Terranosaurus]

The action of the front differential means that which ever shaft is easier to turn and turn on its own. Alternately the other side hub is broken and isn't locking anyway.

What are the symptoms of this problem? IE how did you spot it was doing this?

 

[Johny]

I'm fairly confident the other hub is locking as you can hear it. Furthermore, in recent off-road use I don't think it would have made it if it wasn't locking, as the drive would have been lost to the none locking wheel. (That said it didn't have this problem at the time!).

The fault just occurred without warning and for no apparent reason whilst in normal driving. All of a sudden a heard a noisy winding/clicking from outside the vehicle and at first I thought something had got caught in the wheel. However on further investigation I noted it was the O/S front hub locking and turning the drive shaft and thus the noise from the differential. Putting it in 4wd (and back into 2wd) obviously gets rid of the noise as now both front axles are turning (so the other hub is definitely working).

I'll mark the front drive shaft to confirm if this is turning. If it isn't any more ideas?

Johny

 

[Terranosaurus]

Sounds like the problem I had, which was that the near sid was jammed in the locked position, thus the offside driveshaft rotates and tries to lock the hub, but as this requires a bit of force it gets half way there and then its easier to turn the front prop so it doesn't engage properly and thus you get the clicking noise.

Try checking to see if both sides are disengaging. You shouldn't really be able to hear them lock in, at least I never have and I struggle to hear the feint click when they disengage though I have checked that they do now work by jacking up each front wheel in tun and spinning the wheel whilst watching the drive shaft.

 

[Johny]

I don't think it's the same problem.

Both wheels are locking and unlocking (you can hear them unlock) I'm fairly confident it's the front O/S locking on in 2wd that is causing the problem and also that the noise is the front O/S driveshaft and differential turning. As soon as you engage 4wd and then go back to 2wd (without reversing) the noise goes. If the front N/S was permanently locked this you would surely get the noise consistently unless of course in 4wd.

Thanks

 

[Terranosaurus]

You shouldn't get any noise from anywhere in the transmission except the free wheeling hubs unless something is seriously wrong. Even the hubs shouldn't make anything more than a click as they lock and unlock, but if yours is doing what mine did the hub will not quite be engaging and it will sound like a ratchet, which it sort of is. When you stripped the hubs did you see the dogs (outward facing teet) on the end of the inner sprung loaded locker, these engage with similar teeth in the end of the housing. If they're not quite in thy make quite a noise as they rub on each other - a bit like a gear grating as it goes in if the syncros are worn on your box only continuous.


It took me ages to figure it out and I thought it was the side making the noise too, honestly go and have a look at the other side, it won't cost you anything to look after all. just jack that wheel up and turn it and see if the shaft turns, if it does it locked in still if it doesn't then you've eliminated that as a cause of the noise.

 

[Johny]

I will double check, thanks.

Surely the differential is going to make some noise though if only one of the axles connected to it is turning. Obviously it exists to allow for the difference in movement between each wheel when cornering but this is relatively small compared to one stationary and the other moving continuously?

Did you get the noise all the time as you drove or was it intermittent? If the wheel were permanently locked on the N/S then surely you would get the noise consistently all the time as the other hub tried to engage?

J

 

[Terranosaurus]

An open diff shouldn't make any noise - ever, even if one wheel is spinning and the other wheel stationary it should be quite unless very worn.

Mine used to drive along fine and then all of a sudden it would start making the noise, so like you I'd click it into 4wd to engage the hub and then back to 2wd to avoid transmission wind up. Turned out one hub was locked on solid, took a lot of freeing, using a soft brass drift and a hammer with the hub off the car. The problem was the 2 "break rings" wee worn to the point they would fit inside each other, this means there isn't enough drive available to unlock the hub. Swapping and changing rings from set of spare hubs got me a pair that didn't fit inside each other, now the hubs work perfectly.

 

[drivewasher]

Mine did this often, I found out by jacking car up on front end that the passenger side autolocker was stuck in the locked position, the forward movement of that wheel on the road caused the diff to turn the drivers side shaft backwards (thats what open diffs do) as the drivers side shaft was essencially being "driven" by the diff the drivers front wheel tried to auto lock to shaft in reverse but as I was travelling forwards it was just making a rasping noise.
New A & B brake bands in the passenger side autiolocker did the trick

 

[Johny]

Haven't had chance to get the jack out yet but if one (or both) of the front wheels were locked on wouldn't the front drive shaft be getting rotated all the time?

Try and get the jack out tonight

 

[Terranosaurus]

Haven't had chance to get the jack out yet but if one (or both) of the front wheels were locked on wouldn't the front drive shaft be getting rotated all the time?

Try and get the jack out tonight

Yes. But without jacking up the car it is impossible to tell. The 4wd indicator light doesn't help as it works purely on a switch in the gearbox activated by the lever moving not by the fact that the shafts are turning

Drivewasher is right, I'd forgotten that the free side rotates backwards which is why it doesn't lock in it just rattles along.

 

[Johny]

I marked the front drive shaft, drove along got out and found it hadn't turned. (I did this after the below)

It did however turn at some point between the noise occurring and what I think is the front O/S wheel locking intermittently. Guess the drive shaft could be turning to cause the wheel to lock as you suggested earlier but could the oil in the transfer case really cause this to happen?

Thanks

 

[Terranosaurus]

Sorry nomenclature getting confused.

Propshafts are the thick things running font to back from the transfere casing to the front and rear diffs.

Driveshafts are the roughly inch thick shafts running from the front diff to the front hubs.

Halfshafts (a form of driveshaft) are the shafts inside the rear axle casing taking drive from the rear diff to the rear wheels (the end of the half shaft forms the hub)
The front propshaft may not turn as the driveshafts may be doing all the turning - thats the thing about an open diff any 2 of the shafts can turn independently of the third or they can all three turn together.

Try marking both front driveshafts too.

 

[Johny]

I'm in Sheffield.

My fault. It's the front propshaft that I was refering to. Yes, I appreciate the operation of the diff.

My logic was that if the front N/S hub is locked and i am driving forwards without noise from the O/S hub then the propshaft would be turning.

I will jack it up and find out for sure though.

 

[Johny]

hummingbird; I O U a pint!

Did some thorough investigation last night and found the front N/S hub seized in the lock position and a broken snap ring! It looked like it has never been off so I'm not surprised. Think local breakers had two nearside spares but no O/S when I phoned last week so plan to pick up a replacement today. I will probably fix the other at some point and save as a spare.

I was kind of mislead by the fact I had the car in a local garage and they had said the front o/S was locking on the driveshaft. I assumed they had had it in the air and checked but speaking to them last night they hadn't!

PS: also put new ignition switch in last night. This broke a while ago but I could still start it no probs but the wife couldn't. In fact I'm now struggling to readjust to the normal starting operation i.e. full turn of the key!

Thanks for the help guys

 

[Deleted Member S]

I thought i'd post my question on the back of this thread :roll:
When we were in Yorkshire I had a prob with auto hubs not unlocking :evil: When I removed then to do the hub bearings they were full of gease so I don't think thats the prob. I've heard putting a drop of oil in helps to free them up. The only oil i've got handy at the min is the LSD oil for the back axle would a drop of this be ok :?

Thanks for any advice :smile:

 

[Terranosaurus]

Won't do any harm, its only gear oil.

Not unlocking is likely to be the rings being worn, if they fit fully inside each other they are worn out.

 

[Deleted Member S]

Cheers HB :smile: I will check them but I can't see them being worn as when we were out with you I think it was the T2's first time in 4WD :roll: It did unlock after I backed up quite quickly as I heard it click free :?