Well to be honest I was gutted but it could have been worse, i.e. if I bought an IRD or gearbox and fitted them and it didn’t stop the vibration then I would be seriously ****ed off and gutted! Driveshafts didn’t take long to replace and I am sure they will be knackered some day so I have a spare set now!
The facts I know about this problem are –
1) The driveshafts are not causing the problem!!!
2) It is definitely rev related between 1500-2000rpm, not road speed related.
3) When the complete propshaft is removed it makes it a lot better to a point that is
live able with but the problem is still there. So whatever is causing the problem
is transmitting itself down the prop and up into the drivers seat and through the
body of the car. Also this rules out the propshaft/viscous/centre bearings.
4) It does not have the problem when revving when stationery.
5) When the problem occurs if I press the clutch pedal down but keep the revs
between 1500-2000rpm the problem disappears. So basically when the driveline
is removed from the engine the problem goes.
6) If I apply light pressure on the clutch when the problem occurs it does not stop
the boom/vibration.
7) When at 1500-2000rpm (with the problem evident, for example in 4th gear), if I
shift it back into neutral and let the clutch back up the problem goes.
8) Gearbox and IRD oil levels are fine.
9) All 4 tyres are relatively new, they are micheline synchrone 4x4, the newest tyres
are on the rear
10) I have had numerous people drive the car, from engineers to LR techs that I
know and all have different opinions which doesn’t really help me. Some say it’s
the IRD, others say driveshaft, some say engine mounts and one said flywheel!
To summarise, it only happens when the driveline is connected to the engine, as
soon as the clutch is pressed, disengaging the driveline from the engine the
problem goes.
I have on order a lower rear tie rod because there appeared to be some play in that when I checked it, be surprised if this causes the problem but guess I will find out next week when I fit it, nothing would surprise me anymore. I can only think there is more stress/engine movement on this tie rod when the engine is connected to the driveline amplifying the boom/vibration, that is what I am hoping for anyway!
Noise/vibration/booms etc are difficult to diagnose from on line but its good to get people's opinions, especially if people have had very similiar problems that have been rectified.
Will keep you posted, and thanks to Dave for the input to date.
The facts I know about this problem are –
1) The driveshafts are not causing the problem!!!
2) It is definitely rev related between 1500-2000rpm, not road speed related.
3) When the complete propshaft is removed it makes it a lot better to a point that is
live able with but the problem is still there. So whatever is causing the problem
is transmitting itself down the prop and up into the drivers seat and through the
body of the car. Also this rules out the propshaft/viscous/centre bearings.
4) It does not have the problem when revving when stationery.
5) When the problem occurs if I press the clutch pedal down but keep the revs
between 1500-2000rpm the problem disappears. So basically when the driveline
is removed from the engine the problem goes.
6) If I apply light pressure on the clutch when the problem occurs it does not stop
the boom/vibration.
7) When at 1500-2000rpm (with the problem evident, for example in 4th gear), if I
shift it back into neutral and let the clutch back up the problem goes.
8) Gearbox and IRD oil levels are fine.
9) All 4 tyres are relatively new, they are micheline synchrone 4x4, the newest tyres
are on the rear
10) I have had numerous people drive the car, from engineers to LR techs that I
know and all have different opinions which doesn’t really help me. Some say it’s
the IRD, others say driveshaft, some say engine mounts and one said flywheel!
To summarise, it only happens when the driveline is connected to the engine, as
soon as the clutch is pressed, disengaging the driveline from the engine the
problem goes.
I have on order a lower rear tie rod because there appeared to be some play in that when I checked it, be surprised if this causes the problem but guess I will find out next week when I fit it, nothing would surprise me anymore. I can only think there is more stress/engine movement on this tie rod when the engine is connected to the driveline amplifying the boom/vibration, that is what I am hoping for anyway!
Noise/vibration/booms etc are difficult to diagnose from on line but its good to get people's opinions, especially if people have had very similiar problems that have been rectified.
Will keep you posted, and thanks to Dave for the input to date.