New 122S owner troubles - vibration in reverse

[OriginalMrP]

Originally Posted by Burdekin

Any movement of the wheel? Take the wheel off and try again with the rotating. Check the hub nut. Many years ago I sheared the key on the drive shaft taper on my Jeep, maybe you have the same.

I originally thought that it could be the shoes not seated properly, so new shoes, drums, adjusters etc were replaced and I'm glad I did as the shoes were in a terrible state.
But the noise still occurred on the right rear.

[SnineT]

Originally Posted by OriginalMrP

I've checked the tyre inner wall, wheel, axle strap and wheels arch, all are free from mark's.

When revs are applied and clutch let out the judder occurs at the right rear wheel.

Strange.

I don't want to be the bearer here but it does sound like something in the gearbox and the noise is travelling,

One other long shot, has it had an exhaust recently?

I ask because new exhausts before they coke up a bit bounce sound about, I very much doubt it's this but mentioning it doesn't hurt,

Another thing you could try is to get some help and without starting it put it in reverse and rock the car as if you were bumping it, if you can get two ppl to bump it (don't put the ignition on we don't want it starting without a driver) while you earball the area you suspect it's coming from it may make a more obvious to spot sound, hth.

[142 Guy]

Originally Posted by OriginalMrP

Rotating the right wheel forward, left wheel rotates backwards and prop rotates.

Now, rotate the right wheels backwards, both the left wheel and propshaft fail to rotate.


Clutch wise there doesn't seem to be any issues under load pulling away, I haven't noticed any noise when turning, but I will take it out for donuts tomorrow.

Definitely in the very strange category.

When you rotate the right wheel backwards and the left wheel and propshaft fail to rotate, can you continuously rotate the right wheel backwards? If so, I am baffled. Burdekin's failed key is an interesting idea; but, I also struggle with how a failed key would allow full forward and reverse movement of the complete car.

Just to be clear, the clutch I was referring to was the clutch pack in the traditional spicer power lock LSD. There are also non clutch LSDs (lockers) that can be installed in a Dana 30 housing; but, I don't know whether these are availalble for the Dana 27. Lockers can be particularly noisy. Cleaning that tag to get the identity may help with things.

Here is a nice video from Amazon Cars covering replacement of an open diff with an LSD so you can get an idea of the differences.

https://www.youtube.com/watch?v=BakYNBCclIE&t=93s

If you have drum rear brakes I seem to recall that the Amazon and P1800 brakes shoes have some self application motion in them and that if you don't assemble things correctly that can cause problems. However, I can't see that causing 'I can turn the right wheel backwards until the cows come home but neither the propshaft or left wheel rotate'.

[SnineT]

Originally Posted by 142 Guy

Definitely in the very strange category.

When you rotate the right wheel backwards and the left wheel and propshaft fail to rotate, can you continuously rotate the right wheel backwards? If so, I am baffled. Burdekin's failed key is an interesting idea; but, I also struggle with how a failed key would allow full forward and reverse movement of the complete car.

Just to be clear, the clutch I was referring to was the clutch pack in the traditional spicer power lock LSD. There are also non clutch LSDs (lockers) that can be installed in a Dana 30 housing; but, I don't know whether these are availalble for the Dana 27. Lockers can be particularly noisy. Cleaning that tag to get the identity may help with things.

Here is a nice video from Amazon Cars covering replacement of an open diff with an LSD so you can get an idea of the differences.

https://www.youtube.com/watch?v=BakYNBCclIE&t=93s

If you have drum rear brakes I seem to recall that the Amazon and P1800 brakes shoes have some self application motion in them and that if you don't assemble things correctly that can cause problems. However, I can't see that causing 'I can turn the right wheel backwards until the cows come home but neither the propshaft or left wheel rotate'.

What you say makes sense, without opening the diff though it's hard to tell, I wondered if there's some teeth missing off the pinion in there, might explain the one wheel turns one wheel doesn't like a starter ring missing teeth so the starter can't engage anything,


Also for the OP, it's worth jacking it up and replicating the sound while holding a hand on the driveshaft outer tubing, the more I think about it you may just have a dry wheel bearing and there might not be much oil in the diff, the sound could also be as I said broken teeth swirling around when the shafts in motion.

[powen1]

um ! this is really interesting if you listen to the noise it seems to graduate even when the wheel is not turing at the same speed - unless I'm hearing something else ie not really relating to the wheel speed - could be wrong, I agree the noise could be somewhere else and transmitting to that area - sounds to me like tyre noise but that's been dismissed only other point is that when in reverse the torque on transmission and rear axle will be different to moving forward ? so seems like something is moving, like the idea of the exhaust and would check that out for touching parts but I would assume that would be more like a bang rather than a wasp caught in the rear wheel - good luck will be nice to see the conclusion ! :-)

[SnineT]

Originally Posted by powen1

um ! this is really interesting if you listen to the noise it seems to graduate even when the wheel is not turing at the same speed - unless I'm hearing something else ie not really relating to the wheel speed - could be wrong, I agree the noise could be somewhere else and transmitting to that area - sounds to me like tyre noise but that's been dismissed only other point is that when in reverse the torque on transmission and rear axle will be different to moving forward ? so seems like something is moving, like the idea of the exhaust and would check that out for touching parts but I would assume that would be more like a bang rather than a wasp caught in the rear wheel - good luck will be nice to see the conclusion ! :-)

It's got a deffo spin down sound like a bearing running out of energy hasn't it, I'm actually suspecting the thrust bearing now, I had a Manta A that I put another lump into must be 40 years ago now, it didn't want to mate easily and when it did I had some sort of cardboard rubbing against cardboard sound and dampened feeling when using the clutch,

It's all pointing at a bearing, either the driveshaft one on that side or maybe the thrust bearing so if the clutch isn't smoothish it might be time to get a new clutch kit, still going with the race is broken in the outer driveshaft bearing right now though, to test that jack it up and start it up in 1st gear 1st and then reverse, it should whine and howl if it's dry.

I may have asked already but does the wheel spin freely with the handbrake off?

[powen1]

Originally Posted by SnineT

It's got a deffo spin down sound like a bearing running out of energy hasn't it, I'm actually suspecting the thrust bearing now, I had a Manta A that I put another lump into must be 40 years ago now, it didn't want to mate easily and when it did I had some sort of cardboard rubbing against cardboard sound and dampened feeling when using the clutch,

It's all pointing at a bearing, either the driveshaft one on that side or maybe the thrust bearing so if the clutch isn't smoothish it might be time to get a new clutch kit, still going with the race is broken in the outer driveshaft bearing right now though, to test that jack it up and start it up in 1st gear 1st and then reverse, it should whine and howl if it's dry.

I may have asked already but does the wheel spin freely with the handbrake off?

Good point thrust bearing - jack up the car when you do it run it forward the run in reverse and stick the clutch in to see if any different or wines ! assume you should hear the same if the rear bearing gone ? strange it only does it in one direction ? maybe you don't hear the wine when driving forward normal driving.

[SnineT]

I just had another listen and I don't think it's metallic now, sounds like the sort of sound a slack belt getting retensioned might make or two abrasive surfaces that are supposed to work as one but ones slipping which does say have a good listen around the gearbox bellhousing area.

Need to ask as I don't know the car very well, it hasn't got a CVT box in it has it, like the DAF used to have, aka belt drive.

[OriginalMrP]

Originally Posted by SnineT

It's got a deffo spin down sound like a bearing running out of energy hasn't it, I'm actually suspecting the thrust bearing now, I had a Manta A that I put another lump into must be 40 years ago now, it didn't want to mate easily and when it did I had some sort of cardboard rubbing against cardboard sound and dampened feeling when using the clutch,

It's all pointing at a bearing, either the driveshaft one on that side or maybe the thrust bearing so if the clutch isn't smoothish it might be time to get a new clutch kit, still going with the race is broken in the outer driveshaft bearing right now though, to test that jack it up and start it up in 1st gear 1st and then reverse, it should whine and howl if it's dry.

I may have asked already but does the wheel spin freely with the handbrake off?

The wheel does spin freely and the clutch has smooth engagement through all forward and reverse.

Interesting that you mentioned the driveshaft bearing whilst theres no bearing whine ,there does seem to be excessive play in/out, back and forth.

I've never had a car that's been in the air so many times.

[Derek UK]

Did you get to the bottom of this problem? A long time back I did have a rusted out pilot bearing in the crank that made nasty noises when reversing up a slope. New one a cheap fix except for the labour but I did replace the clutch at the same time.