Vibration through steering column on slow turns - but not always....
So, this is an original style 2017 model G350d with 19" wheels and 275/55 Pirelli Scorpion tyres. Sometimes when parking or doing a 90 degree turn, I can feel a string vibration through the steering column and I can also hear it. It's pretty loud. Mostly RH turns but not always. MB dealer has had the column out and replaced a sleeve? Or bush where the column goes through the body shell. No change. Might even be worse. Dealer is stumped so I'm trying the experts! Any thoughts? Might it be to do with the front diff even?
The other steering issues I have are a) that on full LH lock it feels like the steering linkage is catching on something so you have to jiggle it a bit to free it up and b) the steering doesn't stay aligned - I now have to turn it 5 degrees to the left to travel straight. Any thoughts on these questions please?
Hopefully you will get better responses than me, but here's some input.
1. I never put steering on full lock either side - its just not good. (buggers the relief valve or something)
2. I have an older G350D (2012) and the steering is a little heavy but good and centred. If you have to hold the steering wheel to stop the drift, then it suggests tracking.
3. if you have a worn drag link ball-joint, it can 'jump' when at the extremities of movement...needs replacing. But a main dealer will have seen that right away (I would think).
Turning circle in the 463 doesn't seem to me to be as good as in my 460 (but thats comparing a LWB with SWB). Maybe there should be a restriction on yours? I'll have a look.
I would focus on your point b): "the steering doesn't stay aligned - I now have to turn it 5 degrees to the left to travel straight." That sounds to me like a serious tracking issue, i.e. misaligned wheels. Any tyre shop can check that.
Have you got the original factory wheels fitted. Sometimes with aftermarket wheels the offset is incorrect which will cause the wider tyres to rub on the chassis leg when on full lock.
It could also be that you front diff is locked or has not disengaged properly although that should be obvious from the front diff light showing red on the switch. Have you used the difflocks recently? You would have to have locked the centre and rear diff before you could lock the front diff as they only work in sequence although when you disengage the centre diff they should all disengage automaticaly. If they are not used regularly the activation pistons are prone to seizing. If the front diff is engaged and you make sharp turns on tarmac you will feel a severe judder through the steering and will hear a metalic banging or clanking noise. The steering will also feel vague and the vehicle will track left and right when accelerating.
Regarding the steering wheel alignment I would say if you didn't have this issue before the steering column was removed and replaced by the dealer then they have probably misalligned it when they replaced it. Most likely cause is that they have not put the steering wheel on straight !
Check your tyres for deformation, we've had several Pirelli shod 4x4s with wonky tyres, Pirelli's seem to be very prone to carcase damage.
cheers, Gordon
Did your dealer replace the steering column?
Easy one to try, give the column UJs a real soaking in WD40 etc, drive around on lock to lock a few times, repeat.
Mine seized once I left the car for a few months
any luck fixing the issue?
The last part of the mentioned issue : feels like its catching on full lock , is a 'feature' of the steering setup, which on these models (post 2000, large engines), is no longer straight through from the steering column to the steering box, which is located further out on the chassis. My G400 has this issue as well as a number of others I've tried. Last year I replaced the drag-link and tie rod and all bushes, but it's still there. However, only on full lock to the left, when reversing.
Your main issue of vibration, I would check the front roll-bar and its rubber bushes on the frame. However, whilst they may be good for looks, the tyre size is not what these vehicles, their axles and steering were originally designed to wear. They put a heavy load on the components.
What sort of speeds are we talking? , dodgy cv joint? , bad swivel bearings, but you hope a main dealer would pick up on it?Would be interesting to try it with the front propshaft removed and center diff locked?
At 4 years old, main dealer/MB should be resolving this. I am assuming it didn't knowingly have a smash in the first couple of years?
If it is groaning, not juddering, as you are steering at low/no speed, then that sounds like low fluid in the steering pump. But that's so easy to see/check any garage would pick it up. G350 steering is heavy but should be smooth and precise. Any clunking on turning sounds like a pretty worn joint - again should be easy to see.
I'd be inclined to put standard width wheels/tyres on it. As mentioned, maybe if they have been on for a while and the car is a city car, its had a lot of manoeuvering do do with more rubber putting on load.
Would be interesting to try it turning lock to lock with the front wheels jacked up off the ground, that way stress much reduced?
I would recommend Raj at Suoercar Service
The man is a G wizard and will pin this down in no time I would think
Not too far from you?
https://www.supercarservice.co.uk/
Worth a phone call at least?!?
Can't remember if Mot regulations say 25mm, are we talking older G?
Thanks to all for the thoughts and suggestions. I really appreciate you taking the time. I'm going to follow up on these points, and the dealer has also just identified that I have split gaiters which has allowed dirt ingress to the ball joints, and so a degree of grinding. Parts are on order. Tracking and alignment will be looked at too. So let's see where this leads. To pick up on a few points, the wheels are standard (but I've been thinking about switching to a smaller rim diameter, maybe 16", and possibly going to steel, while keeping the overall diameter around 31") and I agree about the turning circle - supertanker territory - which adds to the grin factor but does mean you reach for full lock when on other cars, you wouldn't. I'm not showing any diff lights but will use the locks and check they are engaging/disengaging.