Dealer misdiagnosis
Discussion
A few weeks back we had a stuck brake on my wife's ML320 (2008, approved-used warranty in place). We had the Mercedes Assist guy come out as we were concerned it may not be safe to drive on. Chap arrived, had a good look, said the piston in the caliper was very hard to move.
Car was recovered to the local Merc dealer who said "no, it just needs a clean up and bit of grease" even after reiterating the road-side guy's diagnosis. They were adamant, did what they said, charged us about £150 and sent us on our way.
Weekend before last the same caliper starts sticking again. Took it in yesterday and now they're saying - you guessed it - the piston in the caliper is stuck. A bit of to-and-fro with the warranty company and they got approval to do that on warranty.
So, going back to the previous visit. As I see it, the dealer tech misdiagnosed the issue the first time round so in my view we should be entitled to a refund. They are, of course, just claiming that that was all it needed at the time and this is a new issue, but I fail to see how a caliper piston can go from working properly to corroded to the point where it's seized up in the space of four weeks.
Where do we stand on this?
Car was recovered to the local Merc dealer who said "no, it just needs a clean up and bit of grease" even after reiterating the road-side guy's diagnosis. They were adamant, did what they said, charged us about £150 and sent us on our way.
Weekend before last the same caliper starts sticking again. Took it in yesterday and now they're saying - you guessed it - the piston in the caliper is stuck. A bit of to-and-fro with the warranty company and they got approval to do that on warranty.
So, going back to the previous visit. As I see it, the dealer tech misdiagnosed the issue the first time round so in my view we should be entitled to a refund. They are, of course, just claiming that that was all it needed at the time and this is a new issue, but I fail to see how a caliper piston can go from working properly to corroded to the point where it's seized up in the space of four weeks.
Where do we stand on this?
8bit said:
So, going back to the previous visit. As I see it, the dealer tech misdiagnosed the issue the first time round so in my view we should be entitled to a refund. They are, of course, just claiming that that was all it needed at the time and this is a new issue, but I fail to see how a caliper piston can go from working properly to corroded to the point where it's seized up in the space of four weeks.
Where do we stand on this?
Dealer can't win can it?!Where do we stand on this?
What if warranty company said no to a new caliper as it is strictly a wear an tear item? Then you'd be thinking the dealer was great for trying to fix it for £150 rather than tell you simply splash XXX on a new caliper when the issue is only a new piston being required.
kapiteinlangzaam said:
How did you pay for the first transaction?
Do you care if you piss the dealer off (i.e. is there an alternative one in the area for future work)?
First time was paid by credit card. Next nearest dealer is over an hour away - I think I see where you're going with this but we'd rather keep them on side.Do you care if you piss the dealer off (i.e. is there an alternative one in the area for future work)?
aka_kerrly said:
Dealer can't win can it?!
What if warranty company said no to a new caliper as it is strictly a wear an tear item? Then you'd be thinking the dealer was great for trying to fix it for £150 rather than tell you simply splash XXX on a new caliper when the issue is only a new piston being required.
But that's not the case is it. To expand upon yesterday's visit, they initially said the piston was corroded and the warranty company refused the claim because they don't cover corrosion. I went back and asked them to have a close look at the piston seal and they discovered it had perished, thus causing water ingress. This then meant the warranty claim was valid as the corrosion was a symptom of the failure of a covered part.What if warranty company said no to a new caliper as it is strictly a wear an tear item? Then you'd be thinking the dealer was great for trying to fix it for £150 rather than tell you simply splash XXX on a new caliper when the issue is only a new piston being required.
So to summarise, they failed to diagnose the issue the first time round and didn't fully diagnose it the second. So your "poor dealer" rubbish doesn't apply here.
BuzzBravado said:
£150 to unbolt a caliper and scoosh brake cleaner around and wire brush the pad runners...... madness. In saying all that though misdiagnosis happens, we cant get everything perfect first time around, a lot of work is trial and error in all sorts of industries.
Merc dealer labour rates are close to that an hour, so not really8bit said:
But that's not the case is it. To expand upon yesterday's visit, they initially said the piston was corroded and the warranty company refused the claim because they don't cover corrosion. I went back and asked them to have a close look at the piston seal and they discovered it had perished, thus causing water ingress. This then meant the warranty claim was valid as the corrosion was a symptom of the failure of a covered part.
So to summarise, they failed to diagnose the issue the first time round and didn't fully diagnose it the second. So your "poor dealer" rubbish doesn't apply here.
Now that you have added extra information my post seems less relevant but you have confirmed what I suspected which is the warranty company saying no at first hence Merc trying their fix to see if it would suffice. So to summarise, they failed to diagnose the issue the first time round and didn't fully diagnose it the second. So your "poor dealer" rubbish doesn't apply here.
aka_kerrly said:
Dealer can't win can it?!
What if warranty company said no to a new caliper as it is strictly a wear an tear item? Then you'd be thinking the dealer was great for trying to fix it for £150 rather than tell you simply splash XXX on a new caliper when the issue is only a new piston being required.
Only it never happened so this post couldn't be more irrelevant if it tried.What if warranty company said no to a new caliper as it is strictly a wear an tear item? Then you'd be thinking the dealer was great for trying to fix it for £150 rather than tell you simply splash XXX on a new caliper when the issue is only a new piston being required.
aka_kerrly said:
Now that you have added extra information my post seems less relevant but you have confirmed what I suspected which is the warranty company saying no at first hence Merc trying their fix to see if it would suffice.
What...If a piston is corroded enough to seize, the caliper needs rebuilding. As pistons don't just seize for no reason on a daily driver. It's almost always a f
ked seal. What the dealer did is called 'a bodge' not a fix.Warranty companies are also pains for misapprehending words like 'corrosion' and 'wear' as a way to get out of paying. Even if its not a consumable or service item.
xxChrisxx said:
What...
If a piston is corroded enough to seize, the caliper needs rebuilding. As pistons don't just seize for no reason on a daily driver. It's almost always a fked seal. What the dealer did is called 'a bodge' not a fix.
Warranty companies are also pains for misapprehending words like 'corrosion' and 'wear' as a way to get out of paying. Even if its not a consumable or service item.
I accept your point regarding warranty companies. However since 8bit said the dealer explained thatIf a piston is corroded enough to seize, the caliper needs rebuilding. As pistons don't just seize for no reason on a daily driver. It's almost always a f
ked seal. What the dealer did is called 'a bodge' not a fix.Warranty companies are also pains for misapprehending words like 'corrosion' and 'wear' as a way to get out of paying. Even if its not a consumable or service item.
8bit said:
"no, it just needs a clean up and bit of grease"
If a caliper rebuild is done thoroughly then yes new piston(s), new dust seal, new bleed nipple and some paint would be what I expect. However on a 7 year old part if there are no obvious signs of the seals being destroyed taking it all apart, cleaning/greasing and reassembling is hardly a bodge. aka_kerrly said:
If a caliper rebuild is done thoroughly then yes new piston(s), new dust seal, new bleed nipple and some paint would be what I expect. However on a 7 year old part if there are no obvious signs of the seals being destroyed taking it all apart, cleaning/greasing and reassembling is hardly a bodge.
Seems like a bit of extrapolation to the extent of the work done. As on further inspection, less than a month later, the seals were found to be 'destroyed' enough to warrant a replacement.There are two scenarios that are viable here.
A thorough inspection was not conducted and they got the workshop apprentice (hyperbole) to blast the caliper with some penetrant, work it free and slap some grease on it.
A thorough inspection was conducted, but by someone incompetent.
As there is no way a seized caliper goes from having seals looking good enough to regrease to f
ked enough to replace in a month.Edit: If they looked marginal, this should have been highlighted and the OP given the choice of a cheap gamble fix or an expensive but robust fix.
Dealers have to be held to a higher standard of work than a DIYer.
Edited by xxChrisxx on Tuesday 30th June 20:10
xxChrisxx said:
As there is no way a seized caliper goes from having seals looking good enough to regrease to fked enough to replace in a month.
Dealers have to be held to a higher standard of work than a DIYer.
There you go, we could assume the seal may not have been damaged on removal & inspection but could have been reinstalled incorrectly at which point the issue is the dealer's quality of work and not to do with the initial diagnosis.ked enough to replace in a month.Dealers have to be held to a higher standard of work than a DIYer.
aka_kerrly said:
There you go, we could assume the seal may not have been damaged on removal & inspection but could have been reinstalled incorrectly at which point the issue is the dealer's quality of work and not to do with the initial diagnosis.
No need to assume anything. In all scenarios the same conclusion is reached to the OPs question.OP said:
As I see it, the dealer tech misdiagnosed the issue the first time round so in my view we should be entitled to a refund.
A dealer charging £150 to 'fix' something, that then breaks less than a month later, is piss poor. Them trying to pass this seizing problem as totally unrelated to the last seizing problem, is so they can save face. The OP deserves a refund.I'd put my money on this being a technicians incompetence/ignorance. There is a reason why premium dealers go straight for the ultra robust, replace rather than rework. It's not squeeze more money out of you, but so embarrassing s
t like this doesn't happen.Edited by xxChrisxx on Tuesday 30th June 20:40
V8LM said:
It will probably end up being argued the way almost all of these things do, and you'll not win: We thought it was this. We said we would do this. We did not say we would fix the problem. We did what we said...
Kick up enough of a stink, they'll fold.The line I'd take is:
Are you really saying that we put it in for work on the brakes, and you wouldn't guarantee that you'd fix the most safety critical component on the car. What if it had stuck on at speed!! Spearing us across the motorway into a bus full of schoolchildren going to the petting zoo.
There is a reason why they are trying to vainly argue that this is a totally seperate issue to the first, identical, issue.
aka_kerrly said:
xxChrisxx said:
What...
If a piston is corroded enough to seize, the caliper needs rebuilding. As pistons don't just seize for no reason on a daily driver. It's almost always a fked seal. What the dealer did is called 'a bodge' not a fix.
Warranty companies are also pains for misapprehending words like 'corrosion' and 'wear' as a way to get out of paying. Even if its not a consumable or service item.
I accept your point regarding warranty companies. However since 8bit said the dealer explained thatIf a piston is corroded enough to seize, the caliper needs rebuilding. As pistons don't just seize for no reason on a daily driver. It's almost always a f
ked seal. What the dealer did is called 'a bodge' not a fix.Warranty companies are also pains for misapprehending words like 'corrosion' and 'wear' as a way to get out of paying. Even if its not a consumable or service item.
8bit said:
"no, it just needs a clean up and bit of grease"
If a caliper rebuild is done thoroughly then yes new piston(s), new dust seal, new bleed nipple and some paint would be what I expect. However on a 7 year old part if there are no obvious signs of the seals being destroyed taking it all apart, cleaning/greasing and reassembling is hardly a bodge. At no point during the original visit did the dealer say anything like "we think it might just need a clean up, if you want then we can try that first at a cost of £150 to you and see how it goes and if it fails again we'll look into it further." If they had I'd have declined and asked them to look into it properly in the first place. If they'd done that then they'd have correctly diagnosed the issue first time round and none of this would be happening now.
ging84 said:
if i had a caliper that was ceasing i would always have a go at cleaning and greasing it, would never go straight to replacing it.
If it was my own car then this - I don't have warranty on mine any more, it's a weekend car so I'm happy to do this stuff on it because I don't need it on a day to day basis. The Merc is my wife's car and this is what gets her to and from work, carts our 1 year-old son around, etc. etc., hence why we keep the warranty on this one as we get courtesy car cover if we need it too.xxChrisxx said:
If it's been sticking on and getting hot, I'd watch out for them saying you need new discs and pads at the back.
Funny you should say that. First time it was in, when they said it just needed cleaned up, they said it needed a new disc on that corner, but not pads. They said the disc was scored on the outside and rusted on the inside. I declined, partly because I wasn't convinced of their diagnosis and partly because they didn't think it needed pads as well and I've always been told to change pads when changing discs. I fail to see how a disc could be corroded on one side if the caliper was stuck on, too.Glad we didn't pay for that now. Funnily enough, this time round they didn't seem to think there was anything wrong with the disc.
Given that this shower are the only dealer any less than an hour's drive away (on a good day) I think we can safely say this'll be the last Mercedes we ever own.
8bit said:
If it was my own car then this - I don't have warranty on mine any more, it's a weekend car so I'm happy to do this stuff on it because I don't need it on a day to day basis. The Merc is my wife's car and this is what gets her to and from work, carts our 1 year-old son around, etc. etc., hence why we keep the warranty on this one as we get courtesy car cover if we need it too.
I don't understand why you needed to pay for them to repair a caliper, but the replacement was covered under warranty Gassing Station | General Gassing | Top of Page | What's New | My Stuff