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Discussion Starter #1
After 21 months driving on Vredestein all weathers with absolutely no issues and having fairly recently had the knuckles changed I'm a bit perplexed and concerned
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car has done 13600 miles, fairly moderate driving which is just over 2000 miles since the knuckles were changed on 20th June and probably the first times since then I've used it on wet roads as we've been away in the motorhome and had a rather nice BMW loaner while my wife's mini was being repaired.

The car handles well in the dry but now on wet roads, even mildly wet it's truly horrible and has very little front grip, scary tbh almost as they've just given up the ghost.

Pressures are fine, tyre wear is even and at least 5mm across the front tyres, same as the rears so nothing obvious and though I haven't jacked up the car I've rocked the wheels and can't feel movement.
It has to be the tyres but I've never needed to change with 5mm left on any previous car so if that's the case I've changed my mind about the vredesteins

I'll probably need to pay a visit to the dealer to have the problem checked just in case they haven't tightened the fixings properly.
 

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Huh?

Lons, this is the exact opposite of what everybody says, post knuckle fix.

Can you describe a little more about what the vehicle does or behave in the wet.??

My experience with the 'crabbing characteristic' was minor, however I did notice that in wet conditions , in small suburban round-a-bouts (something becoming very common now in Aus.) that if a only a minor amount of throttle was engaged the car would want to understeer (push the front end) ….worse the tighter the turn. This correlates with the 'crabbing characteristic', in that the more lock you have, the more out of alignment the front wheels become. To my thinking this was a safety issue ...minor, but possible.

Post 'Knuckle fix, I can not induce the understeer at any of my 'known' spots. The vehicle turns into corners better and when settles in to a 'quick' turn, it feels more 'locked-in' or 'solid' mid corner. To my thinking ..all because, the front tyres are not fighting each other. It just feels that margin more better to drive.

With your GLC, I would ask the dealer to go over the wheel alignment settings, as a full wheel alignment should have been carried out after the knuckle change. Or possibly, go to an independent wheel alignment/tyre service place and get them to check over it/compare to MB alignment.

Your experience is at variance to the rest of us. You deserve better!


Edit: My vehicle: GLC250 Petrol, 37,000KM. Knuckles have done 2,000km.
Bridgestone HP Duellers 20" rotated every 10K, pre-knuckles..fronts were wearing on outside edges. 3-4mm tread left, across all 4 tyres.
 
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Agree with Citizen, all members that have had the fix applied have said it has cured the skipping, something drastically wrong Lons.
 
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Discussion Starter #4 (Edited)
Yes didn't explain it properly I guess. I lose the grip on corners, steering feels light but not really understeer and that's not cornering hard either just normal driving speeds it feels a bit like driving on black ice, it's only on wet roads, grip is there in the dry.

First time I noticed was a couple of weeks ago on a gentle left hand bend doing about 40mph where in the past I could probably have taken it easily at 60+ but I wasn't in a hurry it was raining just enough for intermittent wipers so I put it down to the road surface being oily after a dry spell and I drove with care, roads were dry on the journey home and car handled normally so I thought no more about it.

Happened again, same roads the following week, ( I drive 25 miles to go trout fishing :smile2:) and I've been aware of it since but not had much rain until last week when we had some torrential downpours so Friday morning roads were quite wet so a lot of water near home where you would normally expext some aquaplaning but much better further on with roads just wet no running water and there was no grip.
When I got home I went straight back out in the wifes mini which has FWD and her front tyres are just under 5mm and it handled as it always does like a go cart. The BMW loaner we had was a top spec 320d RWD and it handled beautifully.

The reason I moved away from BMW to Audi was the former car handling in the wet and ice, my Audi quatros never felt short of grip and to date niether has my GLC in fact after the knuckle fix I posted that I didn't notice any difference in handling but I hadn't had a problem with skipping before that just wanted the fix done to future proof the car for when I change. I've been driving for a very long time, had company cars changed every 2 years and covered hundreds of thousands of miles so not inexperienced.

I'm going to drive to the dealer on Monday or tuesday and ask them to check it out and in the meantime had emailed Vredestein UK to ask for an opinion.

Just as an aside to that the Mini was in for a service last week at 13400 miles, which is why I know what her tread depth is and they wanted me to buy 2 new front tyres :surprise:I gave them a firm no though will put some on before winter.
 

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Discussion Starter #5
Citizen613, where are you along the coast in NSW?

Just out of interest as we've probably been around that area, ( I have a brother in Sydney ). Have driven north a few times and last visit I drove the coastal rout from Melbourne to Sydney. beautiful areas.
 

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Lons, my 43 was horrific for the tyre skipping but only at low speeds on full lock, at normal speeds the road holding was brilliant even when cold and wet, there is something wrong with your car hopefully dealer can sort.
 
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Discussion Starter #7
I phoned the dealer and am taking it in for a check later today.
Have just checked the wheel nuts again which are tight and the front pressures are at 2 bar which is what I usually run at as there are never more than 2 of us in the cat and 90% it's just me. Tread measured using a digital gauge this time is 5.1 to 5.45 across the front tyres and no damage as far as I can see. I certainly haven't clipped any kerbs or potholes.

When I wrote down the mileage in my early post it seemed high so since have checked it and it looke as if the dealer has written down the wrong mileage at 11345 when they changed the knuckles on 20th June when it was actually 13345 so I've driven only 560 miles since the knuckles, about right as we've been away for more than 3 weeks in the motorhome. in that time.

Anyway, will be interesting to see what they say this morning.
 

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Discussion Starter #8
Dealer says nothing wrong with it.

A technician took it for a test drive on his own, disabled my dash cam, and reported that he was happy with the car and it's safe and ok. I got that second hand through the service advisor who fobbed me off by saying the new steering geometry would make it handle differently. I fully accept that but doesn't really explain why it's awful in the wet and she couldn't answer that.

The roads were bone dry today so next downpours we have I'll take it back in if possible and press then to look again. However, they had the car for 45 minutes which is far longer than a quick test drive so I'm hoping they found something they'd left loose and tightened it but will find out soon enough. If nothings changed I'll take it in to an independant for check and have a word with MB customer services for their opinion.

I'm of the opinion they didn't believe me which is annoying but at least I know a wheel isn't going to fall off in the meantime.
 

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Frustrating Lons, hope you get it sorted, customer services will just tell you to take it to the dealer - I have been there.
 

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...and the front pressures are at 2 bar which is what I usually run at as there are never more than 2 of us in the cat and 90% it's just me.
Hi LONS,

2 bar sounds a bit low on my estimates …..equivalent to 30psi.
Over the last 2 years of ownership I have settle down to 34-35psi range (2.3 - 2.4 Bar)
To my ham fisted readings, this has evened out the tyre wear across the tread.
Suggest you try a little higher pressure and compare.

Has been difficult to figure out..as both front wheels had toe-in which was only adjusted out a 6 months ago and now recently the knuckle fix. So a moving target ..with a new situation now prevailing post knuckle fix.

Bridgestone Dueller H/P 20". I figure about 10,000km left in the tread ..will see how the next 5,000 goes.
I am starting to get the itch to dump the Run flats and replace with normal construction ...so may not wait for the 10K to come up.
 
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