Vibrating Disco

[Lars L]

I have posted this on the Disco forum, 29 have looked, no reply. Maybe better attention here?

A mate has a 300 Tdi manual Disco with serious vibration issues. A while ago, the transferbox gave up and he installed a second hand one. At first everything was fine, but suddenly this vibration developed.

The Disco is raised 2" and he has installed a caster correction set. When it is parked on level ground, the rear u-joint on the front propshaft is almost at its limit, while the front on is almost straight. The rear yoke is more or less touching the drive member half of the joint. I also noticed that it seems like the gearboxes sit low at the rear end, when looking from the side they are not parallell with the chassis. I have no Tdi to compare with, but on my V8, the box is level to the chassis. Can someone with a manual 300 Tdi just check how one should look?

Then there also was some play in the front drive member, so a bearing change is on the to-do-list.

[jules]

I have posted this on the Disco forum, 29 have looked, no reply. Maybe better attention here?

A mate has a 300 Tdi manual Disco with serious vibration issues. A while ago, the transferbox gave up and he installed a second hand one. At first everything was fine, but suddenly this vibration developed.

The Disco is raised 2" and he has installed a caster correction set. When it is parked on level ground, the rear u-joint on the front propshaft is almost at its limit, while the front on is almost straight. The rear yoke is more or less touching the drive member half of the joint. I also noticed that it seems like the gearboxes sit low at the rear end, when looking from the side they are not parallell with the chassis. I have no Tdi to compare with, but on my V8, the box is level to the chassis. Can someone with a manual 300 Tdi just check how one should look?

Then there also was some play in the front drive member, so a bearing change is on the to-do-list.

In my experience the props are the first thing to look at for vibration.

[Pete Attryde]

I would suggest fitting a double cardon propshaft from a TD5, although it might be easier to get one from someone like Devon 4x4 as they are made to be fully greasable and have the correct flanges fitted so you don't need to change the one on the transfer box.

HTH

Pete.

[Lars L]

To follow up - we have tried another prop, the one from my donor Disco. Does really raising only 2" cause the prop to "bend" this much? He has driven for years before without problems.

Has anybody a chance to just crawl under their Disco to see if the box is parallell to the chassis? Sorry, not too much of them around here, otherwise I could check myself...

[white90]

I would suggest fitting a double cardon propshaft from a TD5, although it might be easier to get one from someone like Devon 4x4 as they are made to be fully greasable and have the correct flanges fitted so you don't need to change the one on the transfer box.

HTH

Pete.

D44 were just selling standard D2 props last time I looked.

fully greasable etc come from the Propshaft Clinic in Bradford

[Pete Attryde]

I bought one last week and it definately is fully greaseable has 4 grease nipples, 3 for the U/Js and one for the slider. I think Liz said they now have them made like this.

Pete.

[Kev Baldwin]

Driveline vibrations on a Disco with a lift is almost certain to be from the front prop. Common complaint. I swapped the front prop on mine for a Double Cardan D2 front prop. Result: Vibrations gone instantly.

[white90]

I bought one last week and it definately is fully greaseable has 4 grease nipples, 3 for the U/Js and one for the slider. I think Liz said they now have them made like this.

Pete.

A new product then.

what they really need is a greaseable ball/socket joint

this is standard on the PSC version

[SteveG]

Tony, this changed after all the posts on D44 forum, yours being one of them, relating to Guy90 buying one and then everyone pointing out that they fail after a set amount of time. IIRC they swapped out Guy's for a greaseable one and now only sell these.

Cheers

Steve

[white90]

Well that's a change for a company to listen.

D44 are at least among the decent ones out there:

Ashcrofts/X-Eng/Mud UK/Maxi Drive/Gigglepin being the others I'd recommend to anyone

[steve b]

Hi Lars, is the castor correction a more recent mod since the lift ? Lots of people here don,t bother with cc for 2" lift which puts the diff end of the prop at more of an angle......if both joints run at an angle this can reduce vibes , also pretty sure the early RRC prop with the open style joint will give more angle of operation and is the same length i think . Finally positive id of fault = take prop off lock ctr diff & try it then .

final thought any broken/worn eng/gearbox mounts?

hope this helps

Steveb

[Lars L]

I talked to the guy over the phone just now. He fitted the caster correction bushings because the steering was vague after the lift. Since then he has driven his Disco for some 100.000 kms without any problems with vibrations. Then suddenly they appear and the rear u-joint is almost fully angled.

And yes, when he takes the prop off there are no vibes any more. As said before, the rear rubber mountings at the transfer box may be knackered as the boxes seem to tilt down at the rear.

Anyway, I have suggested that he checks all the bushings for the front axle, they could possibly be worn and cause the axle to tilt too much.