Changed Clutch and blew the Diff!!

[Aleci]

Hoping that someone might be able to shed some light on this. Sorry its a bit long.

We had to get a new Clutch sorted out and also the steering was a bit loose, so took it into a 4x4 specialist who has done work on the car previously. He changed the Clutch, tightened up the steering, and I drove it round the block just to make sure that it appeared to be running OK, which it was.

Drove home that night and the next day we set off on our trip, which was 4,000 kilometers in 5 days.

Car drove at normal velocity, 110km per hour, no vibration, no problems etc. After about 800 kilometers we blew a tyre, rear driver side, so we changed for the spare and tried to get the original one repaired, but it was a goner, balloon type bulge from the inside out. We managed to get a used spare just to make sure we were covered and off we went.

When we parked up at night, it was the first time that we had driven slow or, in a tight circle, and we were getting tyre screech at less than 10 km per hour, which I put down to the type of tarmac.

We continued on the rest of the way, and apart from a little bit of a noisy clutch change there was nothing too untoward. We stopped at a tyre centre with the intent of buying two new tyres, and mentioned about the screechy tyres, but they could not see any problems, and perhaps it was a little bit of an allignment problem, although there was no vibration, and we should get it alligned once we had completed our journey. They did not have our tyre size.

On the way back, another tyre blew, this time the rear passenger side, and we were forced into using the used spare, so that we could drive the 5 kilometers to the nearest town. It became apparent that the tyre screech was now a lot worse, so we drove at about 20 kilometers per hour, just to get to the nearest town and buy new tyres.

We did not arrive, big bang, and after looking under the car we saw that the oil was pouring out of the rear Diff, caused by a piece of metal that had speared its way through the casing from the inside out, which appears to be a broken Differential Cross Shaft.

Later when I looked, I noticed that the Differential Lever was in forward position, Diff position, but the car had been driving normally, at normal speeds, and I remembered the mechanic telling his guy to take the car out of Diff as he was pulling out of the yard so that I could test drive it. And it drove normally, and I had no need to either check the lever or alter it.

So can someone please tell me what the hell happened, I am assuming that they did something wrong when they put the new clutch in, because the Diff lever is positioned wrong, but as I said it was driving at normal speeds, not with a Diff engaged. On reading up later I noticed about squeaky tyres, blown tires etc on other 4 x 4 vehicles so have just put it all together, but I have to go back to this mechanic and see what happened, and would prefer to know what it could be. Any help would be appreciated.

[Deej]

Sounds very much like you have been driving around with the centre diff locked in high ratio, that would cause all of the problems you have described. This forces the front and rear propshafts to turn at the same speed, which puts an immense load on the drivetrain when turning corners on tarmac. This has in turn forced the rear tyres to turn faster than the road is moving under them, wearing them out very quickly and causing them to blow. The stress on the rear diff has ultimately caused it to fail. It is likely that the front diff and transfer box have also been damaged in the process, even though they have not completely failed yet.

It sounds like the high/low ratio linkage may be broken or disconnected, and the transfer box was in diff-lock high even though it appeared from the lever position it was in diff-lock low. Perhaps the garage either damaged it or forgot to reconnect it when changing the clutch.

I imagine the diff lock sensor/light is broken so you would not have seen the warning light on the dash.

Dave

I don't know how trustworthy this garage is, but it is possible that the diff lock sensor was unplugged on purpose so you wouldn't immediately notice the problem. It may have been broken already, but I have heard of this being done before. I rememeber reading a while ago about a guy who was sold a disco with the transfer box linkages and diff lock sensor removed so that he wouldn't notice the box was in diff lock high, allowing him to drive away with a broken halfshaft.

Edited February 22, 2012 by Deej

[FridgeFreezer]

Does indeed sound like difflock was in. It's easily knocked while working on the car and the linkage could be accidentally moved while doing the clutch if the gearbox is shifted around, likewise wires can fall off the sensor or sensors can fail. Garages are rarely familiar with what the extra levers are for, so as long as it drives they don't notice.

[davyd8899]

agree that it was in diff lock high which caused the blown tyres and the rear diff to go bang.

i would also imagine, as suggested that the front diff and transfer box has been damaged in some way as well.

however, there is no need to remove the gear linkage when changing a clutch, i did mine recently.

as fridge freezer says though it would be possible to knock the lever into diff lock when dropping the gearbox from the bell housing depending on how the clutch was changed, it is possible to do it from underneath, others say the engine has to come out to change it, do you know how the garage did yours?

also how long have you had the car?? from what you have described the lever was in diff lock low while obviously you were in high range to achieve the speeds you say you have.

did you notice the positin f the lever before the cluch was changed? this might provide a clue as to whether the garage was negligable or not.

if approching the garage i would also find out what they actually changed and ask for proof by way of reciepts. things like barings etc all need replacing and dont necesseraly come in a cluch kit. also the cluch fork is worth changing as this is prone to failing after a while as well.

hope this helps.

dave

[Aleci]

Thanks guys. The lever was not knocked into Diff, we had been on freeway for about 200 kilometers and had been in the same gear and about the same speed, so no need to change. I think the mechanic forgot to like it back up because we were driving like that from the moment we picked it up from his place. He builds 4 wheel jobs from scratch, but it was one of his guys that did the work. Now just got to wait and see what he says tomorrow.

[Aleci]

Sorry missed a part, lever was at theock position before it was changed, in diff position afterwards, but driving at normal speeds. To be honest I did look at the lever a couple of times only because subconsciously it seemed wrong, but only use the diff maybe twice a year so did not notice, they screwed up, and I did not pay enough attention. Damn

[Aleci]

Well, the mechanic is basically trying to deny any liability. He says that the rear Diff has obviously blown but that it was old and obviously worn. He has no explanation as to why the car would be in Diff position, but with no reduction, and in any case, even if it was in Diff and not reduced gearing it would not create a problem with the Diff etc.

Now I am pretty certain that if the Diff is engaged but the low gearing is not working and the dash light is not wokring because they forgot to wire it back up, that they are at fault. He says he does not understand how that could happen, I assume it was because they forgot to connect the lever up.

Not being particularly mechanical, as is shown from all of the above, it is difficult to argue with him, because he says the two are not connected, I need to be able to show that it is, so anyone that can tell me what would happen I would very much appreciate a decent explanation. Also I read above that it could creat rpoblems with the transfer box and forward Diff, is this also the case?.

Fact is that the car is in his shop, I have to get it resolved even if I have to pay for it for now, but then I would take him to court afterwards to reclaim my costs, so I need to know what the hell I am talking about, even if its just the basics.

Any help would be great, and thanks for the help so far.

[kiwi_110]

Differential forces are created across axles during cornering etc. This is because the wheels on the inside of a turn do not have to travel as far as the outside wheels so they do less revolutions. The difference in rotational speed across the axles is taken up by the actions of the front and rear differentials and between front and rear prop shafts by the centre differential when disengaged (normal driving).

Regardless of what ratio (hi or lo) you are in, if the centre diff is engaged (locked) while you are driving on a dry and hard (tar-seal or concrete etc) surface, the differential forces across the axles, which area created during cornering etc, may not be able to be fully dispersed and will eventually build up ("wind-up") to a point where they break something in the drive-train. Some dispersal occurs through wheel slippage, which you experienced and which resulted in excessive wear and blow-outs. Depending on the state of the half-shaft and CV splines, and the drive members (flanges) one or more of them might give or an axle differential will. The wound up force has to go somewhere and if the drivetrain cannot spin a wheel enough to relieve the tension because of the hard surface, it will find the weakest point and bust it. The centre diff is stronger that the axle diffs (all the power goes through it), and unlikely to be the one to fail.

If the transfer case Hi/Lo shift levers and Diff lock levers are not able to be connected properly, any 4WD specialist worth his salt should know not to send a "permanent 4WD" out with the centre diff locked and should unlock it by any means before doing so.

[Aleci]

Hey Dude, thanks a lot for the info, at least now I can go back and will know when he is bull****ting me, it looks like this is going to9 end up being a courtcase because he denies any of it is his fault. Nt important that it had the Diff engaged, no reduction and no dash light, he says he is not at fault and even it was engaged it would not blow the Diff. This guy actually build 4x4s from scratch for clients, rather worrying. Anyway, thanks a lot, its highly appreciated.

[kiwi_110]

No worries, I just hope you get a satisfactory resolution.

Good luck!

Ray.

[steve b]

There should be a section in your owners handbook that warns against driving in transferbox difflock on hard surfaces , and to only use difflock on soft or loose surfaces.

Also failing to reconnect any linkages or warning light switchs is grossly negligent imo

...are you sure the rear diff is broken ? under that sort of stress (locked TB diff) its possible the splines in the drive member can be stripped if there is already wear - these are the steel centres with the small plastic cap on in the centre of the wheel

As said above any 4x4 specialist should be fully aware of this

good luck with sorting it out

cheers

Steveb

[Phil Hancock]

...are you sure the rear diff is broken ?

Well the OP did say that the diff cross shaft has exited the case thro the diff pan.

The center diff lock position of 90/110/D1 that i have driven is not forward or back on the gear lever but sideways and the description above reads as though it should be forward for locked. Forward is low range and back is high range, push to the left in either range to lock the diff.

[Quagmire]

Are there no warning signs on a disco anywhere? My old 90 has a big notice on the fuse panel about the centre diff...

[p76rangie]

...are you sure the rear diff is broken ?

Well the OP did say that the diff cross shaft has exited the case thro the diff pan.

The center diff lock position of 90/110/D1 that i have driven is not forward or back on the gear lever but sideways and the description above reads as though it should be forward for locked. Forward is low range and back is high range, push to the left in either range to lock the diff.

Just because you move the lever across to lock or unlock the diff does not mean that it actually locks or unlocks. They can stick in either function. So he most likely moved the lever when changing the clutch. It could have got stuck with the centre diff locked. Therefore it might not have been his fault outside not checking that everything was correct before handing back the vehicle. Also having the centre diff locked makes it easier to line up the input shaft with the clutch when putting it back together. That is, you can turn either of the output shafts to get the input shaft to turn to get it to line up.

He also might not have connect the the lever back up correctly when finishing the job. This may explain why it was in the wrong position. In this case it probably was his fault.

In either case the diff lock light should have been on if it was functioning.

So I do not believe that it is a clear cut case that the mechanic was negligent, But might have been.

[steve b]

Well the OP did say that the diff cross shaft has exited the case thro the diff pan.

oops I did read it , numpty moment I think ...

cheers Phil

Steveb

[davyd8899]

i done the cluch on my disco

At no point on changing the cluch did i remove gear linkage, remove any wiring for the dash light or remove/touch any sensors

so it begs the question was the light working before the mechanic changed the cluch?? if so then there is a reason why he removed the wires to the light. that could be a point to bring up with him.

probably a very long shot but you dont have any pictures with the centre diff light on do you?

it helps to put the centre diff lock in to help line the input shaft up so it could be something happened when he did this and rather fix it he disconnected the dash light. failing that i cannot see any reason the mechanic would need to touch the light, sensors, wiring or the diff lever/linkage

hope this helps

[p76rangie]

i done the cluch on my disco

At no point on changing the cluch did i remove gear linkage, remove any wiring for the dash light or remove/touch any sensors

so it begs the question was the light working before the mechanic changed the cluch?? if so then there is a reason why he removed the wires to the light. that could be a point to bring up with him.

probably a very long shot but you dont have any pictures with the centre diff light on do you?

it helps to put the centre diff lock in to help line the input shaft up so it could be something happened when he did this and rather fix it he disconnected the dash light. failing that i cannot see any reason the mechanic would need to touch the light, sensors, wiring or the diff lever/linkage

hope this helps

Did you remove the gearbox to change the clutch or did you remove the engine. Removing the gearbox will require you to move and unplug the things mentioned. Removing the motor may not.

[davyd8899]

Did you remove the gearbox to change the clutch or did you remove the engine. Removing the gearbox will require you to move and unplug the things mentioned. Removing the motor may not.

i used this thread as a rough guide to do my clutch

http://forums.lr4x4.com/index.php?showtopic=6268

again as you can see, no wires, sensors or anything to do with the diff lock were touched.

as i said i did put the diff lock in to line up the input shaft but that was it

so again if his light was working before the cluch change and not working after the change then i would say the garage was negligable.

but it isgoing to be difficult to prove

maybe someone could start a thread listing good land rover specialists in there area?

[p76rangie]

i used this thread as a rough guide to do my clutch

http://forums.lr4x4....?showtopic=6268

again as you can see, no wires, sensors or anything to do with the diff lock were touched.

Most would drop the gearbox right out so that it is easier to work on. In such cases the wires are unplugged. But as you stated, whether the light was working before they touched it would be difficult to prove.

[Aleci]

They dropped the gearbox to do the change so they removed the centre console, and in fact they also forgot to connect the cigarette lighter as I use that to connect the GPS, and the Dash Warning light was working beforehand, but nothing at all showed this time. Problem now is that I have to pay for the replacement part, and then claim through the courts afterwards, but as I am in Brasil, the parts are costing approximately 3 times the cost of buying them elsewhere, its painful to say the least.

[Ally V8]

Just a thought,I'm thinking you may be on a sticky wicket trying to prove damage to a diff from the CDL being left in its engaged position.My memory of the bulkhead plate on my IIA is that it states "tyre life may be reduced if used for long periods on the road in 4wd" or something very similar.

Point is your truck uses VERY similar parts so LR only saying about excess tyre wear - not transmission damage could be a good basis for the garage to argue it was worn out/failing anyway.

[Aleci]

Well, I managed to get a used Diff. cost me $700.... the joys of living in Brasil.Then discovered a site called www.landroverpecas.com.br that sell direct from the UK, I could have got a brand new Diff, including the deliveryand the whopping 70+ tax, for about the same prices, but oh well.

Anyway, finally got the car back, mechanic still saying that they do not think that they were responsible for anything going wrong.... so drove the car home, I live in a place called Serra de Cantareira, and its only about 18 kilometers from his garage, but its all hills and forest and bendy roads. So drove the car home, bit slow because it was bad weather and as I said, all bends and hills.

Couple of days later we went to the local town, and it was the first opportunity to get it to above 50km, so when we hit 80km, the car is wobbling all over the damn place, so it looked like maybe the Steering Damper had packed up, perhaps after stressing everything with the Diff, the Damper just had enough. So I kept the car down to about 50km and had to put up wth it for about a week until I had time to get someone to have a look for me.

So the first time we went down the hills, back into the city, it became apparent that it could not wait, driving round corners was taking your life in your own hands, and it really was not much fun. Had to pass a friends house to pick him up, and I mentioned about the wobble, and demonstrated by building the speed up on a straight, he was none too happy at the strange sensation of sliding around all over the place.

He asked me to stop so that he could have a look, he also thought it might be the Damper, or perhaps the Swivels. After a look round, he pointed out the 2 rear Tension Bolts that had not been re-tightened and hanging loose, Now I am not sure if the mechanic is taking the tiddle, or if he really is just that incompetent.

[steve b]

Do you mean the rear trailing arm to axle bolts? or the 2 bolts that hold the A frame ball joint to the A frame?

Either way , extremely dangerous and more to the point its not necessary to remove the axle to change the diff....it's not even necessary to jack the vehicle up ! just chock wheels , remove halfshafts , rear prop and then remove the diff

If I were you Aleci I'd get a manual and some spanners and a socket set and get into it yourself in the future , its clear that you may not be getting the service you are paying for.

Cheers

Steveb

[Aleci]

The two torsion bar http://www.4x4abc.com/images/tech/torsions.jpeg bolts were undone. They had jacked the car up, and I assume that they undid the tension bars to give a bit of movement to the axle so that they could remove and replace the Diff.

Got the spanners, got the manual, got the socket set, time is the problem. I do the simple stuff, change the brake pads, shocks, fuel pump, belts etc, but the clutch is too bloody heavy when you do not have decent kit. I have to change the clutch once a year and it is just easier to have someone do it, never had a problem until this time, and I only changed from the guy I used before because he could not do it until a week later, and I had to drive to Uruguay.

This mechanic has just built an Engesa for a client, kit job with a Triton chassis etc. Looks great, http://mecanicabaruel4x4.g3wsites.com/fotos/ but after all of this fiasco I fear for the buyer.