M4 (2018 F82) Rear Diff Failure

alcook · 06-09-2023, 08:12 AM

Obviously the first pace to ask is you guys!

Car (53,000 miles) is in BMW Stratstone after I heard a very soft whine some weeks ago that has got progressively worse. No lights, or codes. I couldn't work out if it was the turbo, gear box or diff as it was hard to locate when driving. No one else could really hear anything, but it was a noise I knew was new.

At 70, noise reflections from the concrete central reservations were quite loud with a high pitched whine. So I stoppped driving and booked it in.

Upshot is I've been told the rear diff has broke.

The kicker here is this started soon after a Minor Service and Rear Diff Oil replacment in March. Quoted repair is around £3.5k. I have no additional warranty (a discussion for another day) and they are looking at some 'good will'.

My starting position is the fact that this starting after a Diff service is not coincidence... I was told there's no leak and everything looks intact.

Searches are throwing up nothing of note apart from a recall in 2016..

Anyone with a similalr experience or advice?

Thank you..

SteveChester · 06-10-2023, 10:25 AM

Not sure I’d be paying 3.5k - loads of second hand ones on eBay for £400-500?

alcook · 06-10-2023, 02:53 PM

Thanks Steve. I was told it'll take 48 Hours for some response. I'll see if they dig their heels in before I look to get a second opinion..

As I want to check if the oil was changed.. And what oil was used...

M4_CaptFlashheart · 07-06-2023, 11:59 AM

I complained to bmw about a noisy diff and they tried to fob me off with some story about it being ‘normal’ for M cars. As an engineer I have to say I wasn’t convinced (??????). Anyway, car booked in for investigation as I was going away for a couple of weeks. I get back two weeks later to say they had to remove the whole diff from the chassis, parts and tooling were required from Germany, diff rebuilt with new seals and all good. I’d noticed it before warranty ran out but on MOT (last day of warranty) there was a small oil weep found by the MOT tester. BMW tried to wriggle out of it by saying it wasn’t found by a BMW technician. My argument was it was found within the warranty period.
They didn’t charge me anything in the end. They did manage to leave some parts unconnected and I had to return to the garage after 30 seconds of driving to be told oh we cant fix it now it’s too late. They gave me an M6 I think it was for the night. Picked car up the next day to find one of my rear lights wasn’t working. It had been clear of faults when I left the garage the previous night. Walked back to service desk to say just switched car on and has a rear light out. Then told I need to buy a new light. I said nope. Then they didn’t have one in stock but they’d take a look. Car went around to the workshop and hey presto, 15 minutes later it was ready and waiting. No charge. So you tell me, did it need a light? They said they had managed to find one in the stores. Give me a break. Total Mickey Mouse dealership. Drove the car home and it was fine from then on but not exactly what id call the BMW M car experience. BMW Chancers more like.

alcook · 07-10-2023, 06:42 AM

Thank you for that Flashheart... We did suspect that other things may happen over time.... But your experience sounds eerily similar in having to fight for something that is clearly out of your control.

Unfortunately, we didn't have extended warranty and were some 12 months out of that period, so we did (not unreasonably) feel we'd have to take some hit. But the circumstances of the failure (literally a few weeks after a service) and some additional information that was divulged as we looked at the settlement options, has meant that we've submitted a GDPR SAR to get some information they wouldn't / couldn't provide at the desk.

I will provide an update as it progresses as it's (as is your tale) definitely something of interest to other owners.... More to follow..

06-09-2023, 08:12 AM	#1
alcook Captain 22 Rep 639 Posts Drives: M4 CP Convertible Join Date: Jun 2008 Location: Yorkshire, UK iTrader: (0)	M4 (2018 F82) Rear Diff Failure Obviously the first pace to ask is you guys! Car (53,000 miles) is in BMW Stratstone after I heard a very soft whine some weeks ago that has got progressively worse. No lights, or codes. I couldn't work out if it was the turbo, gear box or diff as it was hard to locate when driving. No one else could really hear anything, but it was a noise I knew was new. At 70, noise reflections from the concrete central reservations were quite loud with a high pitched whine. So I stoppped driving and booked it in. Upshot is I've been told the rear diff has broke. The kicker here is this started soon after a Minor Service and Rear Diff Oil replacment in March. Quoted repair is around £3.5k. I have no additional warranty (a discussion for another day) and they are looking at some 'good will'. My starting position is the fact that this starting after a Diff service is not coincidence... I was told there's no leak and everything looks intact. Searches are throwing up nothing of note apart from a recall in 2016.. Anyone with a similalr experience or advice? Thank you..
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06-10-2023, 10:25 AM	#2
SteveChester Brigadier General 2472 Rep 4,653 Posts Drives: F82 M4 Join Date: Oct 2009 Location: Chester iTrader: (0) Garage List 2014 BMW F82 M4 [0.00]	Not sure I’d be paying 3.5k - loads of second hand ones on eBay for £400-500? __________________ Steve Roberts UK F82 M4 I'm running the 2024 London Marathon for the British Forces Foundation - https://www.justgiving.com/fundraising/sr5/
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06-10-2023, 02:53 PM	#3
alcook Captain 22 Rep 639 Posts Drives: M4 CP Convertible Join Date: Jun 2008 Location: Yorkshire, UK iTrader: (0)	Thanks Steve. I was told it'll take 48 Hours for some response. I'll see if they dig their heels in before I look to get a second opinion.. As I want to check if the oil was changed.. And what oil was used...
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07-06-2023, 11:59 AM	#4
M4_CaptFlashheart Second Lieutenant 227 Rep 269 Posts Drives: M4 2018 Join Date: Aug 2017 Location: uk iTrader: (0)	I complained to bmw about a noisy diff and they tried to fob me off with some story about it being ‘normal’ for M cars. As an engineer I have to say I wasn’t convinced (??????). Anyway, car booked in for investigation as I was going away for a couple of weeks. I get back two weeks later to say they had to remove the whole diff from the chassis, parts and tooling were required from Germany, diff rebuilt with new seals and all good. I’d noticed it before warranty ran out but on MOT (last day of warranty) there was a small oil weep found by the MOT tester. BMW tried to wriggle out of it by saying it wasn’t found by a BMW technician. My argument was it was found within the warranty period. They didn’t charge me anything in the end. They did manage to leave some parts unconnected and I had to return to the garage after 30 seconds of driving to be told oh we cant fix it now it’s too late. They gave me an M6 I think it was for the night. Picked car up the next day to find one of my rear lights wasn’t working. It had been clear of faults when I left the garage the previous night. Walked back to service desk to say just switched car on and has a rear light out. Then told I need to buy a new light. I said nope. Then they didn’t have one in stock but they’d take a look. Car went around to the workshop and hey presto, 15 minutes later it was ready and waiting. No charge. So you tell me, did it need a light? They said they had managed to find one in the stores. Give me a break. Total Mickey Mouse dealership. Drove the car home and it was fine from then on but not exactly what id call the BMW M car experience. BMW Chancers more like. __________________ M4 AY 2016 M4 SMB 2017 M4 Riviera Blue with CCB's 2018
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07-10-2023, 06:42 AM	#5
alcook Captain 22 Rep 639 Posts Drives: M4 CP Convertible Join Date: Jun 2008 Location: Yorkshire, UK iTrader: (0)	Thank you for that Flashheart... We did suspect that other things may happen over time.... But your experience sounds eerily similar in having to fight for something that is clearly out of your control. Unfortunately, we didn't have extended warranty and were some 12 months out of that period, so we did (not unreasonably) feel we'd have to take some hit. But the circumstances of the failure (literally a few weeks after a service) and some additional information that was divulged as we looked at the settlement options, has meant that we've submitted a GDPR SAR to get some information they wouldn't / couldn't provide at the desk. I will provide an update as it progresses as it's (as is your tale) definitely something of interest to other owners.... More to follow..
	Appreciate 0 Quote