P38A Suspension bush woes

1997 4.6 HSE auto 149k
Suspension bushes were getting tired for MOT so decided to get an indy to change them as I do not have a FBP. They requested polybush as they were easier to fit. Fitted blue "comfort " bushes. Rangey became uncontrollable whenever i hit a pothole above 50mph. Whole vehicle shook and vibrated viciously and could not drive out of it as in wheel balance. With advice from large semi independent garage bushes were changed for yellow polybushes. She is now much better behaved but still feels as if she is on the cusp of uncontrollable when I hit a bump.
Anyone met this before?

Some seem to have had success with polys, personally I think they are the Devils work and they are delusional.
It's all about ease of fitment and pretty colours with those crew, if you can't fit a genuine bush then get someone to do it for you, they will last 4 times longer than poly and ride like it was designed to do.
Poly is for serious off roaders and track cars where refinement is not even factored.
Sure, you can get a poly that has a shore hardness that may be close to OEM but it will never be as good as the real MaCoy which is nice and absorbent but crucially and oft overlooked....torsionally restrictive.
If you want refinement fit original.

Old shocks ,and tyres to hard will also make the axle shudder on pot holes or you could just drive at 49 mph.

oakey said:

1997 4.6 HSE auto 149k
Suspension bushes were getting tired for MOT so decided to get an indy to change them as I do not have a FBP. They requested polybush as they were easier to fit. Fitted blue "comfort " bushes. Rangey became uncontrollable whenever i hit a pothole above 50mph. Whole vehicle shook and vibrated viciously and could not drive out of it as in wheel balance. With advice from large semi independent garage bushes were changed for yellow polybushes. She is now much better behaved but still feels as if she is on the cusp of uncontrollable when I hit a bump.
Anyone met this before?

Click to expand...

Yes, it has been mentioned on here a few times. I cannot remember what caused it though! Think there was a thread called something like "shake, rattle and roll"?

Take it you did the front radius arm bushes? How are the other bushes holding up? IIRC you have to take the drag link and whatever off. Is that all OK?

The other advantage of 49mph is it saves the fuel tank emptying so quickly.
New genuine shocks fitted about a month ago, EAS working fine (Touch wood) and tyres spot on.
I think that was the thread I posted on and got into bother for
Front radius arms and roll bar etc all done at same time.

How are the ball joints. Tracking. Wheel bearings. Take off the centre caps from your wheels silver paste? Bearings fubar,... replace axle.The radius arm bushes are very important in stopping that shake and changing these usually cures this. But metalastik bushes are much better if they are oe quality. PS no tracking adjustment on the back.
Jb

Tracking not sure, wheel bearings were inspected and are fine and steering shocker too

The steering damper won't cause this. The wheel bearings on a p38 are really high quality and can be gone but no movement. Difficult to check by spinning as the axles are all locked. Old tyres can be an issue. These are so old the causes could be anything from the drive train(props VCU etc) to the front suspension. Change heights to see if it makes a difference. These radius arm bushes were a stock land Rover solution pre independent suspension most Indies will press these in for not much.
Jb

Will try that ta