Driveshaft-type noise

[CJH]

After a few days happily bumbling around the Lake District I drove back yesterday and got to within 25 miles of home and started to hear a knocking noise. I heard it first at about 55mph, with the engine under load (slight incline, and I was towing a small caravan). If I backed off the throttle or dipped the clutch it went away. The knocking was related to the road speed, and it seemed to be coming from the back. Handbrake made no difference. So I thought I had a pretty good idea what it was, having read of people who'd found loose driveshaft bolts.

I pulled over, had a bit of a look, and it all looked ok, so I got back in and attempted to drive the last few miles home. On pulling away though it was evidently now much worse than when I first noticed it - now I could hear it at any road speed, and it sounded bad. So I pulled into another lay-by for a better look. I jacked up both sides, turned each rear wheel (felt ok, no noises or wobbles), I even got a hex bit into a few of the inner driveshaft bolts, and the ones I tried were tight. I checked the wheel nuts and the hub nuts. So as it was starting to get dark I thought I'd have one more go at driving slowly home.

When I pulled away again, the noise was gone completely. As I grew more confident I upped the speed to 50mph for the last bit of dual carriageway, and it was absolutely fine - no sign of the knocking noise. As far as I'm concerned, I 'fixed' nothing in that last stop - the noise sounded quite alarming when I pulled over, but when I drove off it was gone.

So my best guess is still that it's one of the driveshafts - maybe the bolts in the outer end. Before I start digging around under there, does anyone have a better suggestion, particularly one that might explain why the noise came and went so dramatically?

[CJH]

PS Kitchen, Ford Transit.

[CovKid]

You may have redistributed the grease. If its not bolts it'll be worn out joint.

[CJH]

Thanks Ralph, that makes sense.

[CovKid]

If joints need replacing Chris, get them from ECP. They do the LOBRO ones which are excellent quality and cheaper than everyone else. I think GSF do them too.

[itchyfeet]

Tonydata (Matt) called me Thursday with virtually the same problem, going away at the weekend, given it a test drive and clicking/knocking from the rear when driving.

Had a look drive shaft bolts were ok, jacked and rotated wheels o/s was clicking, pushed drive shaft in and out and concluded cv was shot.

Next day he took it to garage and it was gone., drove if around no noise.

[CovKid]

I have in the past (in an emergency) punched a small hole in a CV gaiter and pumped it full of grease. Sometimes you'll get six months or more out of a joint by adding grease but wear is wear in the end. Sooner or later it'll either start clicking again or fail.

[CJH]

If joints need replacing Chris, get them from ECP. They do the LOBRO ones which are excellent quality and cheaper than everyone else. I think GSF do them too.

Thank you - I've just placed a 'click and collect' order with GSF for four of their 'premium' CV joints, and with their 'bankholiday' 35% discount they worked out at £27 each. I'll check what brand they are in the morning over the phone, and if they're the GKN Lobro ones I'll go and collect them. If not, ECP have them for £33. The ECP advert shows that the kit includes the boot and clips, and new bolts. The GSF advert shows a splined bit set as a 'related product', so I'm hopeful that the included bolts are the splined sort mentioned in your wiki piece.

There is some in-and-out play in both driveshafts, and from Itchy's comment and what I've read elsewhere that seems to be the clincher. Ever since I've had the van I've had the occasional 'thump' from the left rear when taking up the drive in reverse, particularly up a slope. I wonder if it's related.

[itchyfeet]

There is always movement in the shaft, this is because the distance between cv's varies as the wheel goes up and down, my point was moving it in and out seemed to have stopped the clicking, perhaps moving grease as suggested, or perhaps the shaft got was not freely moving in the cv spline.

[ethelred the ready]

Exact same symptoms I had, dried up CV joint grease, got worse when hot from driving at speed and disappeared when gently pootling around.

[itchyfeet]

So possibly a regrease is all thats needed.

[CJH]

There is always movement in the shaft....

Ah, I misunderstood. So maybe pushing them back and forth was what 'fixed' mine too.

So possibly a regrease is all thats needed.

Maybe so. This could be a use for some of the other 499g of MoS2 lithium grease that I bought for the flywheel spigot bearing? But I don't like the idea of having to punch holes in the boots to do this. Is that the only way to get grease in once they're in situ?

[itchyfeet]

To regrease properly you just have to undo 6 bolts on each CV boot and the whole drive shaft come away with CVs

if you do be warned as soon as the boot is off the cv can fall appart, keep them square to the shaft, I cable tie or two through the cv and boot while you work stops them falling appart when your backs turned.

You need three hands to reassemble

[CJH]

Yeah, that's what I was hoping to avoid by regreasing rather than replacing! So is it not possible to remove the circular clip and squeeze a grease gun in?

[itchyfeet]

Suppose it may work for a quick fix but the boots are quite tight so a syringe would be needed
it's really not hard to do it properly

Shows cable ties