vibrations

Depends on where the vibrations are coming from. If you can feel the vibrations emmenating through the steering wheel it might be misaligned wheels.

Could also be engine mounts?

G's in general are a bit slow (unless its the newer ones), are you sure the lack of power is specific to your G. I've got a 300 which I claim has no power..... :(

Andro:

In my experience the most likely cause for vibrations are any of the three propshafts. They can i) get out of balance or ii) have worn UJ joints.

There are three propshafts in any G: one taking the power from the main gearbox to the transfer case (a), and two joining the transfer case with the front (b) and the rear (c) axles.

I would first see if it's either the front or the rear. This is most common because the longer the propshaft, the more likely it is that it would get out of balance. Also the (a) is nicely tucked between the chassis rails and the main- and the transfer box, which makes it less prone to contamination with water and mud, which are the main causes of wear in the UJ joints.

To test for wear, lie underneath the car and hold each propshaft by a point close to each UJ joint and try to move it up-and down and left to right. If you feel any appreciable movement then the UJ joints will need to be renewed.

To test whether the problem is in the front propshaft, you'll have to remove it and test drive the car in the "S" position of the transfer case. This is because your 230 GE is a 460 series and thus is rear-wheel-drive with connectable front-drive, and in the "S" position you'll only have drive to the rear wheels. If the vibration disappears, bingo! have it rebalanced and/or refitted with new joints.

To test the rear, have it removed and test drive the car with the transfer in its "SA" position. If the vibration disappears, bingo! have it rebalanced and/or refitted with new joints.

Normally, if the vibration appears at a certain speed and disappears over that speed, then it should be a problem of imbalance only.

In any event, the propshafts should be greased every 5,000 miles to prevent wear at the joints.

Good luck

Whilst you're under checking the propshafts start off by shaking the first one out of the back of the gearbox,if there seems to be play in the gearbox do not despair, there is a flange just inside the rear of the box which wears oval and is about £130 repair (cornish price)

I have engine vibations in all gears below 2000 rev's when accelerating!
Have replaced all three engine mounts and have no apparent wear or play in the short
prop shaft.
I read guerdeval's post on play at the back of the gearbox, any futher information
suggestions would be much appricated

Whilst the answers provided for this particular set of vibrations are probably right, it is worth remembering that there can be other causes.

I wasted a lot of time looking at my prop shafts and UJs (on a 280GE) when in fact the problem was distorted brake discs.

I had vibrations at between 50 and 60 mph (80-100kph) on the way up and similar, but worse when braking.

Putting in new discs was the answer; also comparatively cheap and easy. KMS had the discs at a reasonable price.

Front warped disks is a common problem, they are the same as a 308 van, and good motor factors can supply disks for around £35 each and pads around £20 the set, if you are finding that the vibration disapers when braking at high speeds then is is your disks that are warped.

Bill is more accurate in describing my old problem, drive shaft support bearing is what it was I just didn't know what it was called,rog