High revolution vibration at 90 to 110Kph

[Shirley]

A brain teaser, well at least for me?
We have two Vehicles, a 1993 Disco and a Rangie 1990 Classic.
Both are in reasonably good condition but the disco has 180K and the Rangie has 360K on it.
Both have, what we thought were universal problems due to a vibration that comes in about 90kph to about 110kph.
I installed new Prop Shafts on both hoping that this would get rid of the vibration but it did nothing. The vibration was still there and possibly more pronounced.
Both vehicles have the same fault, same symptoms, at the same speed.
One has a Viscous Borg Warner T/F case and the other, I don't know.
One has big K's on it and the Discovery has only half as many (186K).
I can only assume that this is a common problem with Landrover as both my trucks have that particular fault, so I am hoping that others out there have sourced this problem and can tell me what I should be looking for.
Please help if you can...... This vibration is quite bad and I am getting tired of driving at 80 kph on the freeway and it's costing me a small fortune.
Regards,
Shirl...

[DiscoveringAuz]

Have a quick look at your engine and gearboc mounts, my vehicle had a vibe which i put up with for ages, swapped them out and all gone,
Not saying this is your answer but easy visual check will give you an idea and they area cheap replacement

[JDNSW]

Have a quick look at your engine and gearboc mounts, my vehicle had a vibe which i put up with for ages, swapped them out and all gone,
Not saying this is your answer but easy visual check will give you an idea and they area cheap replacement

I agree. If it is prop shaft frequency, as you seem to have satisfied yourself, and the prop shafts are new, unless they are either loose or the flanges are loose on either the pinion shaft or the transfer case shaft, then it is most likely that the residual vibration of the shafts is being transmitted to the body more than it should be. The most likely way for this to happen is through a faulty engine mount or because a sagged engine mount allows something on the engine/gearbox to touch the chassis or body. Other possibilities would be the exhaust or gear linkage or similar touching the chassis or body.

John

[greg smith]

I had the same problem[02 TD5] spent a small fortune-- tyres wheels balancing tyres balancing r propshaft replacing front propshaft--all to no avail, then replaced both engine mounts VIBES GONE!!!!! Best of luck