Gearbox woes

Lemo

In November the gearbox in my 02 Laguna went. I had it replaced, got the ball joints done and full service. Over the Christmas the gearbox went again.

My mechanic now tells me that the gearbox ran out of oil because the "rubber boot" where the driveshaft goes into the gearbox leaked. I was stunned when he told me that he had not replaced it when doing the gearbox first time around. He is saying that it's not standard practice to replace it but I can't believe that.

Surely, you would replace all seals as a matter of course when doing a major job like a gearbox.

What do you guys think?

mmenarry

It would be standard practice to replace any seals that are a beeatch to get to when doing a job like that.

e.g. I had work done on my clutch recently, and had the rear crank seal replaced at the same time, as requires removing the clutch to replace.

Seals on a gearbox would definately by standard practice if the gearbox had to be removed, as would replacing the gearbox oil, etc.

If the seal was already on the way out, there would have been signs of it weeping (oil on bottom of gearbox).

Michael

BrianD3

The boot surely is just to keep the grease in the CV joint? I would have though there would be another seal further in to keep the gearbox oil from leaking. I am not sure about this however.

Did you notice oil on the ground the past few months? Is the bottom of the car covered in oil grime. The Laguna has a plastic undertray under the engine bay if the gearbox dropped all its oil this will be covered in oil for years afterwards. The gearbox holds around 4 litres so you would notice it.

If you don't see any sign of a leak - maybe some idiot forgot to fill the first replacement box with oil

Lemo

BrianD3 wrote:

The boot surely is just to keep the grease in the CV joint? I would have though there would be another seal further in to keep the gearbox oil from leaking. I am not sure about this however.

I know very little about gearboxes but I find what you say makes sense. Maybe my mechanic is saying things to cover up for a mistake. I will only have a major problem with this if he tries to charge me, although I might be looking for a new mechanic :-)

Can't say I'd noticed any oil but, as you say, the tray on the Laguna might have stopped this from accumulating on the driveway as you would normally expect.

Thanks. I'm preparing myself for an argument so this gives me some confidence.

BrianD3

You will have more ammo if someone here could give a definite answer about the driveshaft boots/seal question i.e. does the driveshaft inner boot seal the gearbox and if so is it normal practice to replace the boot when replacing the box.

If the box is sealed in a similar way to say a crank pulley then the seal should definitely have been renewed when the box was replaced. The box, its seals and the work carried out should all be guaranteed. Was it a main dealer that carried out the work? Was the first replacement gearbox a new or 2nd hand one?

Lemo

The work was done in a SIMI garage (not a main dealer but reputable).

The gearbox was reconditioned and came with a 1-year warranty. The difficulty for the garage will be that the gearbox crowd will probably not be willing to honour the warranty if the garage failed to do the seals properly.

So, the garage may have to shell out for a gearbox which might tempt them into trying to get me to at least contribute towards it. Let's see...

AMurphy

Lemo wrote:

In November the gearbox in my 02 Laguna went. I had it replaced, got the ball joints done and full service. Over the Christmas the gearbox went again.

My mechanic now tells me that the gearbox ran out of oil because the "rubber boot" where the driveshaft goes into the gearbox leaked. I was stunned when he told me that he had not replaced it when doing the gearbox first time around. He is saying that it's not standard practice to replace it but I can't believe that.

Surely, you would replace all seals as a matter of course when doing a major job like a gearbox.

What do you guys think?

The rubber boot keeps the CV grease in the inboard CV joint, not the oil in the Gearbox. So is it the joint of the gearbox that's gone.
the cv boot rotates with the shaft and joint, not the CV boot is attached to the box and the shaft spins in it.

The seal, where the shaft exist the box, is usually a simple seal and reuseable, IF NOT DAMAGED. on repair or assy. It's a simple job to replace item.

However, you say it was rebuilt in Nov and now, early Jan. That 2months.
Any gearbox that is leaking that much oil in tht little time is noticable, so is there a good spraying of oil spun off the shaft and getting all over the engine and gearbox, youd have a mess down there, and trailing along the bottom of the car all the way back, not a little drop and every time you reversed out of a parking spot, youd have left a little puddle... if not... I suspect no oil ever in the gearbox, not that it leaked.
How many L does this box take.
My engine leaks about 1/2 a liter evey week and it leaves on hell of a mess and trail. so judge from there.

even if you have a inboard axle stub that is bolted into the diff. These do not leak any oil through the bolt into the CV joint.
and even if the CV joint boot did fail (no need to change that if repairing a box.), youd only have grease flung all over the engine, not the contents of the gearbox.

got a pix of this failed Boot/Seal, whatever is supposed to have failed?.

And when you say the "gearbox went", what exactly are the symptoms.
and if out of oil, refill it and 1) determine if it leaks as stated and 2) if it resumes "working". Any gearbox, even low in oil will have difficulty shifting, but usually suffer no permanent damage.

Forgot to add, if they actualy mean, a seal where the Gearshifter shaft enters into the box, and that shaft is at the bottom of the box, then it would leak without a whimper.... but would leave Poodles. Again, why was it damaged?.
Such a shaft has a similar seal to that used on the driveshafts, ie a horizontal "V" type seal. Not really necessary to change to repair a box.

some idea of what they may look like here;
http://www.mspseals.com/
http://www.blue-diamond.co.uk/products/sealdesigns.html

does'ne make sense yet laddie.

Lemo

AMurphy wrote:

And when you say the "gearbox went", what exactly are the symptoms.
and if out of oil, refill it and 1) determine if it leaks as stated and 2) if it resumes "working". Any gearbox, even low in oil will have difficulty shifting, but usually suffer no permanent damage.

This is what happened. I drove on the motorway from Dublin to Newry. Near the border, it popped out of 5th. I put it back in and a few minutes later, it popped out again. Within a few miles I was having trouble selecting third and then when I stopped and tried to pull off again there was a heavy clunk. I pulled in a few hundred yards down the road and couldn't move it again. It must have been stuck in a high gear because even with the stick in neutral it would cut out if you let out the clutch.

I never noticed any oil on my driveway or around the engine (although I did not look very clsely at the engine). It was towed from Newry back to the garage in Dublin so I didn't get to see these seals etc.

Could a gearbox last two months with no oil without me noticing anything unusual?

Thanks for your help. I'm really suspicious about why the mechanic is blaming this rubber boot when it almost certainly does not seal the gearbox.[/I]

AMurphy

And What was wrong with it the first time it quit on you?. Same or different problem.

Soulds like one of the shifter forks may have come loose on the shifter rod, so now it is stuck in some gear, probably the last one it was in, even if so, it should rotate, unless you have some item like a roll pin, usually used for keeping the selector forkst attached to the shifter rod, jammed into the gap between two gear teeth, then it would rotate almost one complete revolution ,for and rev, but that's all. oil or lack of it, would not make any difference to such a pin.

if your box, has little or no oil, I could see it lasting (working) several months, depending on load, but it would get increasingly noisy with time as the gears and bearings wear down and more difficult to get into gear.
Synchros do not work very well dry or even close to dry.

If you park the car in the same spot every day/evening, you'd notice the build up of oil over a 2 month period.... only takes me about 5 days to mark a stop.
I had an old Fiat once with a driveshaft seal gone, if stopped leaning to one side if would leak about an eggstand/cup full in a few hours, easy to notice. Even with that seal as bad as it was, it went for months with no problems, untill I got round to repairing it.
Mothers car, an Escort had a noticable leak, also from a driveshaft exit and never had a problem with it.
also, remember the driveshaft exit point is central in the diff and about 2" in dia. The diff itself is about 10" diameter, so you'd have a couple of inches of oil always in the box, It's not going to leak a whole lot once the level goes below the lip of the seal, assuming there was any to begin with.
With some boxes, the normal oil level is below the shaft lip, so you can remove and change the shafts, without having to remove the oil first.

So was the report it had NO oil or LOW oil, and has it been removed and disassembled, or still in the car, etc. What's the current status.

Would it go into any other gear after this event. Cause if the fork came loose onthe rod, you should be able to select another gear, though it will simply lock the box, being in 2 gears at one time.
If the rod itself came undone, you should not be able to select another gear as the ball detents would be locked.

True, I find the boot story lacking substance also.