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Discussion Starter #1
I drove my car from Gloucester to Tenby (winter storage).
Over the Summer months' I'd used the car quite a bit and there were no warnings of any rumbling noises in the drive train. When I set off for Tenby everything was OK, with 40 miles to go I stopped to refuel and it was at this point I realised I had a problem. On slowing down - when the speed got to 20mph or less I heard CLUNK CLUNK CLUNK .......etc (very mechanical & quite loud) from the rear of the car. As soon as the lights changed to green and I started off, I heard it again - but only up to approx 20mph. I stopped and felt the diff' casing it was very hot (I knew it was full of oil). I decided to carry on with my journey and once I was travelling everything was alright - no noises or vibrations.
This weekend was the first opportunity I've had to investigate: If I hold the rear wheel (either or both sides) at 12:00 position and rock the wheel (into the car) it I can feel play.
I removed the rear axle sump plate and out came plenty of oil, not smelling burnt and with NO debris, bearing shells, swarf, etc. I removed the prop' shaft and inspected the UJ's: all seem good with no play whatsover. The prop support bearing housing seems ok in that it spins freely, there is slight play in it. The doughnut does show signs of partial fatigue and has a few cracks but it's not falliing apart and nor degrading away!.
Any ideas anyone.........as to what the CLUNK CLUNK CLUNK could be?
 

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Could be one of several things, if you get a clunk on acceleration or decceleration or when changing gear at low speeds it is likely diff. backlash, this is were the pinion drive in the diff needs adjusting or diff reshiming, you will get a small amount of movement in the prop before the drive is taken up this is normal, but shouldn't clunk
sadly:( this will necessitate a strip down, rebuild and setting of the backlash. it's unlikely to be uj's or driveshaft donuts as your likely to experience this at other speeds also plus this is more of a vibration not clunk.
Possibly worth talking to Charlie Skinner at Cloveleaf Transmissons in Cumbria, he rebuilt mine and does most peoples including the classic dealers.:)
 

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the play in the bearings is fairly normal, there are well documented cases of cars failing MOT's even with brand new bearings. So I doubt that is your noise.

Are you sure it's transmission and not something in the suspension at the back?, bushes on the Tee bar for instance?

Or even the exhaust banging on something, it's easy to be fooled by noises like this. I had mentally written off my centre bearing over the weekend, but the vibrating noise I heard at 75MPH turned out to be a loose joint on the rear exhaust bracket... wierd:rolleyes:
 

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Discussion Starter #4
I spoke with Charlie Skinner at Cloverleaf transmissions, he was extremely helpful and based upon my description of the noise he doesn’t think there is a fault with the rear axle, more so the fault lies with the drive shaft, UJ’s, rubber donut or something else. I have the drive shaft with me at home and I think I’ll take it to a specialist for an inspection. opinion. I can’t do much more until I see the car again at Christmas…….
 

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Discussion Starter #5
clunk clunk

I have now found the problem.......
I removed the prop-shaft but couldn't see anthing wrong as the UJ's seemed free to move. When I re-looked it again later in the week, I realised that one of the UJ's was seized in one direction only - this is something I'd missed before.

Anyone who has a 'clunk-clunk' noise make sure you check the UJ movement in both X & Y planes. It sounds obvious after you've found the problem..........

I removed the UJ to find a dry sized joint in one of the four bearing cups of the UJ.
 
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