Help me troubleshoot a ticking sound (with videos)

[Andy135]

#24, thanks John, I'll check with Martin to see what the factory records suggest. If it is a Quaife ATB then what's the inference for the clunking sound? In your post #10 you suggested that this could be normal/expected behaviour from an ATB. Yet the sound and vibration appears to come from the offside hub.

I should add that I took the car out for an evening blat last night and it performed faultlessly - certainly nothing untoward from the diff or hub.

#25 that's helpful to know Olly. Thank you.

[John Vine]

#26:  It's not unusual to hear a gentle ticking from a Quaife ATB when pushing the car to and fro.  My 2008 R400D has one and I can often hear a discernible ticking sound when I push the car in and out of the garage.  However, it's nothing like the tapping/clunking in your recordings (but then I've never tried to record it close-up).

JV

 

[Andy135]

#27, that's interesting. Remember how I originally started off describing the sound as ticking, due to the fact that when pushing the car into and out of the garage it's much a much softer tick or click (to my ear at least) than when holding my phone up close to the wheel hub to record those videos.

[Wrightpayne]

On my car ('98 dedion / sierra diff) the drive shaft joints have a spring inside them both ends that sort of self centres the drive shaft, sort of spring loaded at both ends.

I wonder if one of these has broken giving a different sound when the dedion is on full droop?

If you grab the drive shaft and try and move it left to right in the horizontal plane does one side feel different to the other?

Ian

 

 

[John Vine]

#29  ...on full droop?

Hmm...a thought (although it may not be significant)...

When you jacked up the car to make the recordings, were the axle stands under the chassis or the deDion?  If the latter, the shaft wouldn't droop, of course.  

JV

[Andy135]

#29, this sounds plausible. To my ear it does sound like something vaguely springy. I'll have to get back under there and test the lateral movement of both shafts to see if there's a difference.

#30, under the chassis, so yes, the shafts were at full droop.

[Andy135]

#29, Ian there's no noticeable difference between the lateral movement of either shaft. I did notice that both shafts feel mildly easier to move towards each hub, and mildly firmer when moving towards the diff. Don't know if that tells us anything other than the spring pressures for each shaft are similar, therefore unlikely to be one broken?

#30, here's another recording, this time made at standing height, and with the shafts in their normal operating positions. Sound a bit like a finger of metal is being put under tension and is twanging back into place.

[Andy135]

A quick update on this. Martin Phipps at Caterham has been very helpful and confirmed that the car was fitted with a Quaife ATB.

Given the fact that the car runs and drives well I'm minded to put the ticking sound down to an idiosyncracy of the ATB unit for now and not lose any sleep over it. Or to put it another way, just drive it until whatever is causing the ticking becomes more obvious, if not the ATB.

[John Vine]

Good news about the Quaife, at least in terms of the (lack of) repair costs.

I tried to listen to your latest recording, but couldn't really hear much at all (and yes, I use earphones as I'm a little challenged in the ear department).

A close-up recording like the earlier ones would help (with the driveshafts not drooping), but probably now you feel you've done enough investigation!

JV