[krat]

Hi all,
Need some advice on a possible suspension issue on the Vitara. Currently fitted with Iron Man Nitro shocks and springs (possible 45mm lift).
The vehicle is mainly used on the beach and dunes but nothing hardcore.
For quite a while now when heading out over the dunes on the beach access tracks, when I get to the lumpy bits where deep holes have been made diagonally to each other up the hills ( where other vehicles have dug holes with say the drivers side front wheel and the passenger back wheels) the rear suspension makes some horrible thump noises as you pass over them even at low speed.
Sounds like the spring on one wheel is extending fully unrestrained into the holes on one side while the other side is compressing on the higher ground. ( Doing the flex thing).
Can anyone explain why this is happening.
Does this mean my rear shocks are stuffed or is there some other problem going on. Have had a look at the suspension and it all looks in place.

Thanks,
Kev.

[fordem]

Have you checked the upper control arm joint?

[krat]

Thanks for the response fordem.
I haven't looked at the control arm at all, only inspected the springs and shocks.
Am I looking for broken and bent bits or is it more complex.

Kev.

[fordem]

My temptation is to tell you to take it to Pedders and have them perform their multi-point inspection...

On a more serious note - you're getting a knocking underneath a twenty three year old car - why did you limit the inspection to the springs & shocks - there's a whole raft of rubber bushes that can be worn or torn, and that's before we even get to broken or bent - anything that is bent, broken, loose, torn, or worn can cause a knock - either do a proper inspection yourself or get a proper inspection done.

The rear suspension is a three link suspension, two lower trailing arms and a wishbone shaped upper arm which links to the top of the pumpkin with a "ball joint" similar to that used for rack ends - the upper control arm is responsible for lateral location so it is under some degree of stress anytime the two sides of the rear suspension do not move together - I suspect the joint may be worn - it's not the easiest of things to see on an inspection, which is why I asked if you had checked it

[pete_79]

Have you tried parking it crossed up (with the wheels as you described what happens in the dunes), getting out and shaking it side to side?

Even better if you get someone else to shake it while you crawl around listening for where the noises are coming from.

As fordem has said there’s any number of wearing parts that could be making noises.