TR674 Posted August 17, 2018 Report Share Posted August 17, 2018 Hello kind folk. Another question I need to ask. When decelerating from a cruise, there is a loud knock from the driver's back wheel. But not always. Sometimes this happens from a light acceleration from a standing start. Hard acceleration/deceleration does not reproduce the knock. Going over bumps, manually shaking the car does not reproduce the sound, so I don't think it is suspension (shock) related. I've taken the wheel off to inspect the area, and nothing is visibly broken. Swing arm is intact. My question is , would this likely be from worn cv joints, worn wheel bearing or swing arm mount wear? Regards Craig Quote Link to post Share on other sites
Mike Herlihy Posted August 17, 2018 Report Share Posted August 17, 2018 Hello Craig, Clonks from the rear are a pretty common affliction and unfortunately can come from various scources. Have you got wire wheels? Once the splines wear these will make a noise as the loading changes direction under acceleration and braking. With the spinner done up tight play won’t be detectable with the wheel off the ground. Another favourite is the differential mounting brackets on the chassis although by now most of these will have modified at some point. Play in the sliding splines of the standard fit driveshafts is another coupled with backlash in the diff and play in the u/j’s. No doubt others on our excellent forums will come up with suggestions. I could go on but my money’s on the wheel splines. Mike Quote Link to post Share on other sites
TR674 Posted August 17, 2018 Author Report Share Posted August 17, 2018 Mike steel wheels. Sound is not central ie diff location but more at the wheel location. Craig Quote Link to post Share on other sites
Mike Herlihy Posted August 17, 2018 Report Share Posted August 17, 2018 Ok let’s see what others come up with. If it’s a loud noise from the specific area of the wheel then I would look at the half shaft assemblies. It’s extremely unlikely to be something drastic like the drive flange being loose on the stub axle. As you probably know these are extremely difficult to separate from the taper. It’s possible I suppose for the wheel rim nut tapers to wear so that the nuts aren't pulling the wheel down completely but never come across that. In 40 years of TR ownership with 4 types the only one that didn’t have rear end noises was a live axle 4! The others were all IRS cars. Quote Link to post Share on other sites
DaveN Posted August 17, 2018 Report Share Posted August 17, 2018 Outer universal joint? Quote Link to post Share on other sites
Waldi Posted August 17, 2018 Report Share Posted August 17, 2018 Hi Craig, Is the knock harmonic, then it is probably related to rotating parts. If irratic, now and then, not in a rhythm, it is more likely suspension/chassis/etc. related. Waldi Quote Link to post Share on other sites
RogerH Posted August 17, 2018 Report Share Posted August 17, 2018 Hi Craig, here is an almost complete list of possibilities - https://www.tr-register.co.uk/forums/index.php?/topic/66819-irs-rear-end-clonking-possibilities/ Roger Quote Link to post Share on other sites
TR674 Posted August 17, 2018 Author Report Share Posted August 17, 2018 Roger I'm leaning towards trailing arm bushes. With the car jacked up, the wheel is firm, no play at all. I'll have a microscopic look over the weekend....... Quote Link to post Share on other sites
tr6tuga Posted August 17, 2018 Report Share Posted August 17, 2018 Had similar noise and its was rear spring rubing trailling arm bed, have a look with a mirror.easy to sort Quote Link to post Share on other sites
ChrisR-4A Posted August 17, 2018 Report Share Posted August 17, 2018 Rear shock mounting bolts, difficult to get really tight. Quote Link to post Share on other sites
Sapphire72 Posted August 17, 2018 Report Share Posted August 17, 2018 (edited) I'm leaning towards trailing arm bushes. With the car jacked up, the wheel is firm, no play at all. You've ruled out the rear hub, which would be a great danger, if the wheel had any play in it. If the TA bushes were worn, I don't think that they would clunk- they are just rubber with a steel center spindle. However, the TA brackets, themselves, have a tendency to crack & separate- that could cause a clunk against the box steel frame. Get your eyes up in there with a strong torch/light source, see what you can see. The loose lever-shock bolt- check the easy stuff out first. The exhaust hangers are notorious for breaking & noise making. You should have a hanger at the back of the gearbox & two hangers in the rear. Also, the rear prop shaft u-joint is under the most stress. You can move the axle half-shaft u-joints with a long screwdriver shank to check them for unwanted play. Of course, cracked differential mount bracket & pin are the real noise makers, that would be right-front side of diff. The exhaust system/diff need to be removed to see up there. And, then there is the diff internals...that would not be so sporadic, more a regular noise. Edited August 17, 2018 by Sapphire72 Quote Link to post Share on other sites
TR NIALL Posted August 17, 2018 Report Share Posted August 17, 2018 Put the Car over a Garage Pit and put the Car into second gear, you get down in the Pit with a good Torch then get someone to rock the Car back and forth your sure to find the problem. Quote Link to post Share on other sites
Ben Freer Posted August 17, 2018 Report Share Posted August 17, 2018 Put the Car over a Garage Pit and put the Car into second gear, you get down in the Pit with a good Torch then get someone to rock the Car back and forth your sure to find the problem. I presume you put the car on axle stands before engaging second gear Niall ! (sorry couldnt resist due to being on second glass of 12 yo Knappogue Castle ) My money is on UJ or loose shocker BTW.............. Quote Link to post Share on other sites
TR NIALL Posted August 18, 2018 Report Share Posted August 18, 2018 Ben you need to stay off that 12yr Old Plonk why would you need Axle Stands your standing in the Pit. Quote Link to post Share on other sites
Waldi Posted August 18, 2018 Report Share Posted August 18, 2018 Because Ben thinks the rear wheels are spinning????? Quote Link to post Share on other sites
TR NIALL Posted August 18, 2018 Report Share Posted August 18, 2018 Because Ben thinks the rear wheels are spinning? But Niall and Waldi know they ain’t. Quote Link to post Share on other sites
TR674 Posted September 12, 2018 Author Report Share Posted September 12, 2018 Niall, rocking the car stationary doesn't recreate the knocking sound whilst driving. It has got worse when I took it out for a drive a few weeks ago. I took it for a drive this morning and 200m from my house something finally broke as it is now making a constant noise like a ball bearing loose in the plastic wheel cap. I don't have time now, but over the weekend I'll take the back wheel off and all should be revealed....... Thanks Craig Quote Link to post Share on other sites
Waldi Posted September 12, 2018 Report Share Posted September 12, 2018 Craig, Look at it from the positive side: now you will find the defect easier:) Waldi Quote Link to post Share on other sites
TR NIALL Posted September 12, 2018 Report Share Posted September 12, 2018 Niall, rocking the car stationary doesn't recreate the knocking sound whilst driving. It has got worse when I took it out for a drive a few weeks ago. I took it for a drive this morning and 200m from my house something finally broke as it is now making a constant noise like a ball bearing loose in the plastic wheel cap. I don't have time now, but over the weekend I'll take the back wheel off and all should be revealed....... Thanks Craig Hopefully it won’t be to expensive. Quote Link to post Share on other sites
Mk2 Chopper Posted September 12, 2018 Report Share Posted September 12, 2018 I'm looking forward to hearing what you found Quote Link to post Share on other sites
TR674 Posted September 25, 2018 Author Report Share Posted September 25, 2018 (edited) Axle out, wheel hub side CV joint is past it's used by date. You will have to use your imagination as the photo won't upload............. Upload worked third attempt..... Edited September 25, 2018 by TR674 upload photo Quote Link to post Share on other sites
peejay4A Posted September 25, 2018 Report Share Posted September 25, 2018 Glad you found the problem. Those are actually universal joints, not CVs. It sounds as though the needle bearings have broken up and I guess you can feel that as you articulate the outer joint. Quote Link to post Share on other sites
Mk2 Chopper Posted September 25, 2018 Report Share Posted September 25, 2018 Is it something you can do or just swap out the drive shaft/axle? Quote Link to post Share on other sites
stuart Posted September 25, 2018 Report Share Posted September 25, 2018 UJ`s are easy to replace. Stuart. Quote Link to post Share on other sites
astontr6 Posted September 25, 2018 Report Share Posted September 25, 2018 9 hours ago, TR674 said: Axle out, wheel hub side CV joint is past it's used by date. You will have to use your imagination as the photo won't upload............. Upload worked third attempt..... It does not look like that they have seen a grease gun for many years? I suspect that was the cause of the problem? Bruce. Quote Link to post Share on other sites
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