Freelander 1 KV6 Vibration

I am getting a terrible vibration at 35mph+. So far I have done the following:

4 Tyres (new and balanced twice)
4 Wheels (new and secondhand)
New Front propshaft
VCU (reconditioned from Bell)
Both intermediate bearings with GKN
3 rear diff mounts
2 rear drive shafts

The vibration/resonance is evident when:

Full propshaft and VCU fitted
Front propshaft only and VCU fitted

But not there at all when:

Rear propshaft only and VCU fitted.

Before I throw in the towel and take it to a garage, is there anything else I should be looking for from people who had similar experiences?

TIA

V6ES_Simon said:

I am getting a terrible vibration at 35mph+. So far I have done the following:

4 Tyres (new and balanced twice)
4 Wheels (new and secondhand)
New Front propshaft
VCU (reconditioned from Bell)
Both intermediate bearings with GKN
3 rear diff mounts
2 rear drive shafts

The vibration/resonance is evident when:

Full propshaft and VCU fitted
Front propshaft only and VCU fitted

But not there at all when:

Rear propshaft only and VCU fitted.

Before I throw in the towel and take it to a garage, is there anything else I should be looking for from people who had similar experiences?

TIA

Click to expand...

Hi

Engine mount ?
IRD ?
Prop shaft ?

Certainly check lower engine mount.
Has VCU been tight for long? Could the IRD have been damaged.
Check for free play in IRD pinion.

2 easy checks may lead you there.
I didn't think anyone else had a V6 !! Worth repairing.
Also, check for free play in front driveshafts but not likely to be influenced by front prop.

V6ES_Simon said:

I am getting a terrible vibration at 35mph+. So far I have done the following:

Click to expand...

Front drive shafts are the likely cause.
If recently replaced they aren't GKN shafts.
Or if original, the inboard joints are worn which causes binding and power unit shake.

There in an another possibility that the IRD output bearing has failed, but that's less common.