Mercedes GLB - DPF

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Fri 24 Jun 2022 17:44
Mercedes GLB - DPF - Chris79

Sat in the Merc dealership this week waiting for my car to be sorted, eavesdropping on a conversation with another customer.

Basically an couple with a Mercedes GLB on which the particulate filter had clogged up. They had tried all sorts but the answer was a new one. The cost? £7000

Apparently the engine is transversely mounted with the DPF sandwiched between the back of the engine and the bulkhead, in order to replace it you need to remove the entire engine and gearbox. To be fair to the dealership the conversation was preceded with the statement “don’t worry it will be covered under warranty”

Nevertheless I almost fell of my chair. Another warning about only buying a diesel if you usage and needs justify it!

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Fri 24 Jun 2022 20:49
Mercedes GLB - DPF - DavidGlos
Wow, I pity anybody picking up the bill for that outside of warranty. It’s exactly this sort of thing that writes off cars at a relatively young age, as they become beyond economic repair.
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Sat 25 Jun 2022 16:11
Mercedes GLB - DPF - Steveieb

My daughter traded in her Audi A3 tdi after all attempts by the main dealer failed to cure the DPF light coming back on.

But these DPF cleaning companies claim they can sort the problem for £250 once it has been returned to them.

understand this is a growth industry with high margins but the question remains how long does the cleaning treatment last before it becomes evident that only a new DPF will fix the problem permanently ?

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Sat 25 Jun 2022 16:49
Mercedes GLB - DPF - daveyjp

The cleaning lasts long enough for a punter to get rid of the car, whuch would be my rhoight process.

No amount of cleaning will get rid of the ash in a DPF which is as hard as concrete and in small bore channels. Once it's full it needs replacing.

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Sun 26 Jun 2022 09:42
Mercedes GLB - DPF - John F

Knowing very little about caring for a fuel of satan engine I wonder if there is preventive maintenance or driving behaviour that might help? I'm sure everyone has followed a diesel emitting a cloud of noxiousness during a possibly rare heavy right pedal episode. Would 'red-lining' it regularly help to stop a DPF clogging up? Does economically keeping the revs below 2000 reduce a DPF's longevity?

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Sun 26 Jun 2022 09:49
Mercedes GLB - DPF - Adampr

Yes, you just have to drive a reasonable distance at a reasonable speed and you don't get the problem. The DPF 'regenerates' from time to time to keep itself clean. The problem comes with people driving short distances at low speed.

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Sun 26 Jun 2022 10:03
Mercedes GLB - DPF - badbusdriver

Yes, you just have to drive a reasonable distance at a reasonable speed and you don't get the problem. The DPF 'regenerates' from time to time to keep itself clean. The problem comes with people driving short distances at low speed.

Not sure what happened in the case of the old couple when they bought the Merc GLB, but it sounds like the salesperson should have at least tried to steer them away from diesel given their usage. Not sure how many would actually do that though?.

Quite a number of years ago (probably mid noughties), when it was time to change my wife's Motability car, I was in a small independent local Fiat dealership looking at the Doblo (might have been the Idea). The owner/salesman asked about our usage and suggested the 1.4 n/a petrol would be a better choice for us than the 1.3 turbo diesel I had in mind.

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Sun 26 Jun 2022 11:47
Mercedes GLB - DPF - RT

Yes, you just have to drive a reasonable distance at a reasonable speed and you don't get the problem. The DPF 'regenerates' from time to time to keep itself clean. The problem comes with people driving short distances at low speed.

It's also necessary to use the correct oil - DPF-equipped cars need "low SAPS" oil which is part of the ACEA specification - using high or mid-SAPS will rapidly fill up the DPF with ash, that can't be burnt off by regeneration/.

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Sun 26 Jun 2022 11:55
Mercedes GLB - DPF - pd

On the rare occasions I encounter dpf issues it isn't the dpf which is the root cause. It is usually a fault elsewhere causing it.

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Sun 26 Jun 2022 12:52
Mercedes GLB - DPF - elekie&a/c doctor
The situation is only going to get worse as petrol particulate filters are now being fitted . Time to get Hercules ready for use .
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Sun 26 Jun 2022 16:38
Mercedes GLB - DPF - sammy1

Yes, you just have to drive a reasonable distance at a reasonable speed and you don't get the problem. The DPF 'regenerates' from time to time to keep itself clean. The problem comes with people driving short distances at low speed.

The Welsh GOV are debating introducing a blanket on all 30mph speed limits reducing them to 20mph across the whole of Wales. I cannot see how this is going to help the diesel drivers let alone anyone else wishing to drive here. I would not be surprised if something similar was to be adopted elsewhere in the UK in the future. If this does happen it would appear that ICE cars are doomed sooner than might be imagined.

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Sun 26 Jun 2022 17:31
Mercedes GLB - DPF - Andrew-T

<< The Welsh GOV are debating introducing a blanket on all 30mph speed limits reducing them to 20mph across the whole of Wales. >>

Surely the perfect way to get clean air would be to reduce all speed limits to zero ?

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Mon 27 Jun 2022 10:20
Mercedes GLB - DPF - expat

The cleaning lasts long enough for a punter to get rid of the car, whuch would be my rhoight process.

No amount of cleaning will get rid of the ash in a DPF which is as hard as concrete and in small bore channels. Once it's full it needs replacing.

Sounds like another good reason not to buy a secondhand diesel.

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