Gearbox woes with a happy ending (and pics)

[blade900]

Just over a week ago I started hearing an unusual noise coming from the rear of the car on the passenger side. A sort of whirring metallic sound. It really took the enjoyment out of driving the car. After much searching on this fine forum it seemed that I might have a gearbox problem, uh oh!

I called my local Mr T who very kindly informed that they would relieve me of 45 quid just to have a look at it. All done with a smile. The thieving pikeys!   s:evil: :evil: s:evil:  

The car is out of warranty so I took it to a local garage that I know and trust who did some initial investigation. They suspected as I did that something was amiss in the gearbox but admitted that they are no experts. This dealer (Cartell near Peterborough) didn't charge me a penny. They recommended a gearbox specialist that they use (as do the main dealers apparently!) who should be able to give me a proper diagnosis.

So off I went to Trade Transmissions, again in Peterborough. As soon as the guy heard the noise he said he was 99.9% sure it was the main drive bearing causing the problem. This was going to be expensive   s:cry: :cry: s:cry:  

He said that he could possibly pull the bearing with the box in situ and if this was the case it would keep the cost down. Otherwise the gearbox would have to come out.

Well I've just picked it up and am delighted to say that he managed to extract the bearing without having to remove the box. This is the offending item



And this is the inner part that was causing the problem, check out that pitting!



Trade Transmissions have done a superb job and I'm a happy bunny again. It cost me £280 which although is a lot of dosh could have been much worse.

Just thought I'd share that with you, it might help others with a similar problem in the future. My car has only done 44,000 miles and has a full service history. It seems that this may be a weak point in this gearbox but is fairly rare apparently so please don't panic. I'm only saying it because of what I've been told.

The 2 still rocks   s:lol: :lol: s:lol:

[Anonymous]

so at what stages were you hearing these noises?

was it in a certain gear or at certain revs aswell?!

[blade900]

It was most noticable when driving at a constant speed up to about 2k RPM. Above that the noise was still there but masked by the road and wind noise. Heard in all the gears but as it was the main drive bearing that makes sense. Didn't hear it at idle and it disappeared when the clutch was depressed.

Anyone else had a similiar problem? The guy that fixed it couldn't really give me a reason why it had failed but did say that he had worked on other Toyota gearboxes (not MR2) with the same problem.

[darrenjuggins]

Hi,

Apparently the bearing are an issue, I had mine done at about 80k, which apparently is far longer than it would have been if my box had been in the avensis....

Lucky for me it was done under my warranty, I'd forgot all about it until you mentioned it..... So maybe something for higher mileage people to watch out for....

Cheers

Darren J

[Anonymous]

i had gearbox failure due to this issue

[Anonymous]

Had mine done at 53000mls

[Anonymous]

I've got the same problem, but bought a used gearbox to replace mine.

[Anonymous]

That is certainly one fucked up bearing. Good to hear that it's probably better to get it sorted by a specialist though.

[onion86]

Dammit got this with mine now   s:shock: :shock: s:shock:   whiring sound when in gear (every gear), disappears when out of gear and slightly grindy/grumbly/whiny when letting the clutch out.

Is there anyone in my area that could double check if the sound mine is making is like this or has any advise before I go to shell out £400 I don't have to hopefully fix a bearing? as: http://www.mr2roc.org/phpBB3/viewtopic.php?f=11&t=21985&p=273141&hilit=gear+box#p273141 (£280 I wouldn't mind so much) I'm not too fussed on how far away if I can just drive over at the weekend, need to meet more people off the forum too. Take it this is quite a big job having to take the gearbox apart, not something I can try myself  s:) s:)  Anyone know of any garages around South West that have had this done?

I'm assuming if left making the annoying noise something will eventually pop and probably kill the gearbox?

[edward.carter]

Mines been making the noises for a little while now too, its booked in for a week today to be done. Yep, i think if you do leave it for too long the bearings will eventually fail and probably take the gearbox with it.

as for replacing box or repair, im not sure, depends how much a 2nd hand box would cost, and you have always got the worry of not knowing condition of the internals on that one, and would it go again. i think if it were to happen to me again, unless 2nd hand box was much cheaper and condition/mileage guaranteed i would probably still fork out for the repair.
Touch wood hopefully my repair will go ok next week and i wont need to buy any more bits!!

[kanujunkie]

mines just been done as well, input shaft centre bearings and main shaft bearings as well and second gear synchro.

btw i have a spare box here if anyone wants it, its a j-spec 5 speed, has a crack on one of the mounting bolt holes, but in the 30K it was on mine, never had an issue. I'm open to offers

[edward.carter]

Mine may need 2nd gear synchro too, going to wait till its stripped and they have had a look inside. But as for the bearings they are definately shot

[blade900]

I'm assuming if left making the annoying noise something will eventually pop and probably kill the gearbox?

The answer to this one is definitely yes. The guy that did mine said that I had done the right thing by bringing it straight in. Otherwise it would have been a much bigger bill. I'm afraid I don't know of anyone in your area but what I would say is try and find a gearbox specialist. People who specialise in a particular area are more likely to do a good job in my experience. Oh, and avoid Mr T at all costs! Hope you get it sorted   s:) s:)

[onion86]

mines just been done as well, input shaft centre bearings and main shaft bearings as well and second gear synchro.

btw i have a spare box here if anyone wants it, its a j-spec 5 speed, has a crack on one of the mounting bolt holes, but in the 30K it was on mine, never had an issue. I'm open to offers

Howcome you had yours out if there was nothing up with it? you put a 6-speed in didn't you?


Wish I was still in Sheffield I actually knew people up there that could recommend places. Don't want to end up with anywhere like the reconditioning place you mentioned in the other thread Stu.


Found a few places in Bristol, I'll do a bit of research:

http://www.gearboxesbristol.co.uk/
http://www.grgb.co.uk/
http://www.llewellins.co.uk/ or these guys that are industrial specialists, guess they'd not do my 2.

Not every manual transmission requires a full rebuild; we are able to replace bearings only if the transmission is noisy, replace synchro rings if the transmission has poor gear selection. This service reduces the costs to up to 50% compared with a remanufactured transmission

Sounds promising.

[SteveJ]

mines just been done as well, input shaft centre bearings and main shaft bearings as well and second gear synchro.

btw i have a spare box here if anyone wants it, its a j-spec 5 speed, has a crack on one of the mounting bolt holes, but in the 30K it was on mine, never had an issue. I'm open to offers

Howcome you had yours out if there was nothing up with it? you put a 6-speed in didn't you?

Nope - it was in there whilst his original 6sp was being 'repaired'

[kanujunkie]

Steve's right

noisey 6 speed removed, new clutch fitted and 5speed put in

6 speed held for when the clutch next needed repairing and reconditioned just before

5 speed removed, new clutch fitted and 6 speed put back in

my clutch change times are every 30-32k so its not too long to hold the box for

[heathstimpson]

What wastegate pressure do you run on your turbo day to day Stu  s:?: :?: s:?:

[kanujunkie]

10psi high boost 5 low boost

[loadswine]

Or 15 if I'm behind you!   s:lol: :lol: s:lol:

[enid_b]

here's one for you then.

if the gearbox main bearing starts making a noise (ie its broken) what happens after that, does the gearbox explode? do the wheels lock? whats the synopsis?

how long from noise to total destruction anyone in the know?

why would the bearing fail? what would cause this?

im in an inquisitive mood today

E

[ChrisGB]

here's one for you then.

if the gearbox main bearing starts making a noise (ie its broken) what happens after that, does the gearbox explode? do the wheels lock? whats the synopsis?

how long from noise to total destruction anyone in the know?

why would the bearing fail? what would cause this?

I'm in an inquisitive mood today

E

If the bearing is just starting to go, it will be running on a surface that has become broken and unable to fully retain an oil film. This leads to the wear rate increasing. Small metal particles will be shed into the oil while it wears, but if sorted quickly, should not be enough to damage anything else (on a good day). Left for longer, the bearing will start to shed more and more products of wear into the oil. The bearing could just colapse, leading to bits of roller cage and balls floating around in your gearbox and an auful lot of noise. It could sieze (I recently saw a siezed bearing that had just rotated in its seat until it cut its way out of the end of the gearbox), it could just sieze solid and lock the wheels.

The more crud that gets into the box from a disintegrating bearing, the more chance you have of damaging other parts. Noise to total destruction could be anything from less than a second, to thirty thousand miles or more depending on what has gone wrong and by how much.

Why would it go? Two reasons really in a healthy bearing (you can have manufacturing defects cause the failure too). The oil film has been penetrated under load (shock loading from nasty gear changes can do this, or running too much torque through the box, or dropping the clutch violently, even labouring the engine at very low speeds and big throttle openings can do it). Or alternatively, although the oil film did not breach, the steel parts of the bearing have become deformed under load. A small deformation (again, all the same possible causes as before.)

Alternatively, the box may be suffering from overheating (oil film fails under load) or corrosion (a lot of the EP additives in gear oil can react with moisture to form corrosive environments that etch the bearing surfaces). This latter failure mode is a good reason to run an ester synthetic gear oil in a car that is not used all the time as these tend not to have the sulphate or chloride ions available to produce the corrosive environment in the presence of moisture.

Last and least likely, shaft resonsance can build up if a box is used in unfamiliar modes (like modifying an engine where its vibration modes change significantly). This resonance can lead to oil film being breached. Hope this helps your curiosity, not that I have ever investigated gearbox failures where a well known F1 team had box failures as a result of engine timing changes:wink:

[kanujunkie]

for the purposes of internet searching the shock loading that Chris is refering to as shock loading is actually refered to as Brinelling, the other one that causes problems with bearings is when the car is parked up, the rollers in the output or main shaft bearings push the lubricant film aside and a small number of rollers take any applied force which can damage the rollers or raceway, this is then compounded on movement of the bearing and so wear starts

worst case scenario of bearing failure is when you just pour the gears out, when we removed one at Marks and opened it, ball bearings from the bearings had impacted bolt heads and passed through them and also parts of the internal casing, were talking about forces on par with a bullet from a gun.

one big problem we have on our box is that some of the bearings have plastic raceway guides, this is the bit that holds the ball bearings in place as they rotate around the raceways, these wear and allow the bearings to move around more, more the movement, more the noise and more the wear, partly a bad design and partly cost cutting.

if anyone wants some more info on bearings makeup and wear then i can scan my notes from the course i did on them and post them up

[ChrisGB]

for the purposes of internet searching the shock loading that Chris is refering to as shock loading is actually refered to as Brinelling,

if anyone wants some more info on bearings makeup and wear then i can scan my notes from the course i did on them and post them up

That was the word I could not remember  s:oops: :oops: s:oops:   I for one would be interested in having a read on the bearings if it is not too much trouble. I'll go get me anorak out of the wardrobe.

Chris

[enid_b]

thank you for that detailed reply, both of you.

these sorts of things really fascinate me. i dont know why, they just do,

cheers

J

[Anonymous]

To make it even more simple, you understand the principal of pre-cats and the damage they can do in an engine - bit's of ceramic floating around in the engine oil, which eventually wears other parts out and eventually making the engine go bang - well bearing failure due to either cheap parts, bad design or generally over powering the gearbox can lead to the same thing happening in the gearbox - bits of metal floating around in the gearbox oil damaging other parts, which eventually leads to the box going bang.

Not so technical but the same result.  s:lol: :lol: s:lol:    s:lol: :lol: s:lol:  

Rob.