My R reg. Almera has a knocking from the drivetrain. It sounds just like a shot CV joint (I had one go on a Cavalier) but the symptoms occur when driving in a straight line as well as going around corners.
I have jacked up the car and can?t feel any play in the wheel bearings.
The knocking is audible at lower speeds when accelerating or under engine braking in the first two gears upto 2500 rpm. When over 2500 rpm the knocking starts to ?balance out? and becomes a rumble, in the higher gears there may be a rumble but road, wind and engine noise are more predominant.
In hot weather the problem seemed to clear up after 5 or 10 minutes driving, in cooler weather it might take 30 minutes the problem to go quiet.
I started to suspect a gearbox driveshaft bearing so removed the gearbox filler plug and a trickle of oil came out, so it wasn?t low on gearbox oil. I emptied the gearbox oil and the magnet on the drain plug had some swarf attached to it but it didn?t seem excessive (how much is excessive?). I refilled the gearbox with oil as described in the Haynes manual. No change.
The clutch works OK and gear changes are as good as all the front wheel drive cars that I?ve had.
Does anybody know what the problem might be?
If it is the gearbox, what should I expect to pay for a fitted recon job? I bought the car a couple of years ago for £900 and have so far been impressed with it?s economy and reliability.
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I guess you will already have done this but it is worth mentioning. Have you checked your driveshaft joint rubber boots? If one has split you could have lost a lot of the grease, and water and dirt could have got in.
Ron
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You were right to mention it because I hadn't. When I first heard the knocking it sounded like the CV joints, so I jacked it up and checked the rubber boots, they were OK. Thats when I also checked for play in the wheel bearings.
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I had it up on axle stands this weekend to check for play as the problem seems to be getting worse. I ran the engine in fifth gear and there is definitely a rumble which sounded as though it was coming from the gearbox area. I took it off the axle stands and then found it almost impossible to get into any gear, reverse was graunching most painfully. Eventually I managed to ram it into first and drive it up the driveway, then I rammed it into second and took it on the road and then rammed it into all the other gears after a couple of minutes driving the situation got back to as it was before putting it on axle stands. Phew!
On Sunday night I took it out and it was difficult getting it into first gear for the first time. It now seems to have normalised as to how it was before I put it on the axle stands and I am now convinced more than ever that the gearbox is on its way out.
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Sounds very strange. Sounds more like a problem with the linkage than with the gearbox. Have you checked the condition of the engine and gearbox mounts?
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sounds like diff bearings have gone , when it was jacked up this would put more stress on them by the driveshafts hanging , causing internals to move, i guess it is quite loud .
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Worn diff bearings would cause the gear selection problems though. I don't think they'd make a knocking noise either.
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Whilst it was on axle stands and I was checking for play. I put it in gear with the engine switched off and rotated a wheel manually. There was about 1 inch of rotational play at the wheels edge before the other wheel rotated in the opposite direction (differentials do this).
Is that amount of play reasonable?
When I rotated the wheel continuously I was unable to hear any knocking, probably because the diff wasn't under load, or probably because the gearbox driveshafts weren't turning (engine switched off).
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The 1" play is normal.
Can you feel and up/down side/side play in the output shaft where it emerges from the gearbox - this would indicate failed diff bearings. Normally failed diff bearings make a whine, not a knock.
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There was no up/down side/side play on the driveshafts between the gearbox and wheels. There was a few milimetres of in/out play but I think this is normal. It sounds like the problem isn't with the diff.
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The problem has been getting slightly worse. You can now hear the gearbox rumbling whilst in neutral at tickover, when I depress the clutch (disengages drive to the gearbox)the rumble disappears.
I took the car to my local branch of Mr. Clutch who also diagnosed gearbox driveshaft bearings, they quoted a fitted replacement recon gearbox at about £650. I got a similar quote from a local transmission workshop and they also quoted me about £400 to repair my current gearbox but I suspect that once they have it in pieces they might discover that it is beyond economical repair.
The car is probably not worth £650 so I am going to get rid and get another car.
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