Vibration at 40 to 45mph

Hi chaps. My jimny as a vibration between 40 and 45mph. It’s not to bad but I don’t like it. Now I know this can be down to a number of things. I am counting out brakes as it happens when not breaking. The car has not done many miles from its last mot which it passed with no notes made, so I am counting out kingpins. Sort of leaves the tires or is there something else I have overlooked. Michael 

It could be tyre balance, the usual range for kingpin "death wobble" is 45 - 55mph, you are just under this so worth getting the balance checked. But assuming its not the tyres read on;

I would check each front wheel assembly yourself, irrespective if it passed the MOT or not. 
Get the wheels off the floor and feel for any play. If you can feel some do it again with the brake pedal pressed, play still present the Kingpins are likely, play gone then its wheel bearings.
Check your steering ball joints etc.

Mine passed every MOT it had, but the kingpin bearings were shot when I took them apart to re-grease, so its likely yours are also. More so if your swivel chalices (Tm Lambert), balls to me and you, are rusty and rough.   

IF everything looks good (assuming tyres are balanced), then its likely that the pre-load presented by a the kingpins / ball joints when new has diminished, its simply wear and tare on the components. You could try adjustment washers under the kingpins to add it back, as sold in the Big Jimny Shop ^^^^^.
OR you could fit a steering damper.
Its  a love hate split on here over dampers, they can mask a developing fault and should not be needed on a car with new components.
That said Suzuki issued a "fix it bush kit" for the G3 and then fitted a damper as standard on the G4!

I have a damper and love it, but it will not fix damaged steering components.

Good luck


Mike

Thanks, some very good information. I think I will go for the steering damper option to start with. It’s just too cold and dark to start taking too much apart.

Ok that's cool.
But I do suggest whilst your are under it fitting the damper you have a good look / feel of all steering parts, even the arm bushes. There is no guarantee a damper will mask issues, but it does make the steering less "wobble happy".
I run a standard vehicle and the cheapest "land Rover" based damper kit available works for me. Not worth spending extra for premium dampers kits unless you like the look or have large tyres etc.

Good luck
Mike

Yes I will also give it a good look around. But kingpins unless they are very bad can be a sod to fault spot. I no longer have a ton of car tools, given them away over the years due to being unable to work on modern cars I have owned. So if a kingpin is bad it will need to be the local garage to sort out.

Kingpins are easy to check, just jack up a front wheel and try wobbling the wheel top to bottom, if there is play then the kingpins are shot. Try side to side movement as well.

One side of my Jimny had top to bottom play, the other didn't but the kingpins on both sides needed replacing.

If it isn't kingpins or tyres (balance) then it will most likely be a bush, I would look in the wiki on what to check for.

A steering damper won't solve the vibration, it will just mask it a bit through the steering wheel, but the problem will still be there.

I have made a few 210 mile round trips just recently, before I did my kingpins and fitted a damper, my arms were tired out after 5 hours driving. Now with the kingpins done the steering wheel wobble has mostly gone and the damper makes the car less twitchy, especially when it is windy. The result I no longer feel tired out after 5 hours driving.

The car needs to go in for its mot in March, I will have them check the kingpins over, I am just too old to crawl around cars now. By the time I forked out for the tools, the garage would of done the job for less. I do understand that the damper is just a mask but it all helps. I only purchased the jimny to cover short trips that are killing my diesel. But I do like things to be correct.