Noisy Diff - pinion bearings !! UPDATE.

Discuss problems you have had or are having with your Z4
User avatar
sure2drive
Member
Member
Posts: 85
Joined: Sat Oct 27, 2018 2:57 pm
Location: New Forest, Hampshire

Noisy Diff - pinion bearings !! UPDATE.

Post by sure2drive » Mon Feb 18, 2019 1:41 pm

Hi all,
Just got back from my local Independent BMW garage, small but good team. Bought my 2.0i SE 2008 roadster 4 weeks ago with 45K and 3 owners, good history. Noticed a whine type noise when warmed up, coming from rear. Couldn't figure out what it was so asked garage to check. verdict "extreemy noisy differential pinion bearings on accelleration" . At the moment the noise is quite low when driving but it's frequency is just the right pitch to get on my nerves, and prognosis is that the bearings will get worse over time and fail.

So, what to do? new diff costs around £1000 plius VAT plus fitting, thats £1500 on a car costing £6000. Bit of a blow :(

Could fit a second hand diff for less, but how could I be sure it was any better? Can thses be rebulit/repaired, or is there any other option I might be able to consider.

Couldn't find out much at all about this on searching the forum (maybe I used the wrong criterea) and I wondered if this is a common problem, and what advice I may find, so I would be very grateful for others opinions.

Thanks in advance for any help.
Last edited by sure2drive on Mon Mar 18, 2019 6:53 pm, edited 1 time in total.
If you want to give God a good laugh,...tell him your plans.

Scooba_Steve
Lifer
Lifer
Posts: 4752
Joined: Wed Feb 19, 2014 3:01 pm
Location: NW London

Noisy Diff - pinion bearings !! advice appreciated.

Post by Scooba_Steve » Tue Feb 19, 2019 10:43 pm

Where did you buy from, private or trade?

A trade purchase has 30 day right to reject.
3.0si Sport: F10 Illuminated ZHP, Retrofit Cruise, OE Stubby, Gaptech RCH+, Kenwood BT73DAB + Handsfree, HIDs, LED Sidelights, OE LED Number Plate Lights, Custom LED strip bootlight.

User avatar
NickDE
Senior Member
Senior Member
Posts: 1067
Joined: Sat Oct 01, 2016 12:21 pm
Location: Newcastle upon Tyne

Noisy Diff - pinion bearings !! advice appreciated.

Post by NickDE » Tue Feb 19, 2019 10:54 pm

Buy a secondhand diff. I've not heard of issues with diffs on Z4s so you'll probably be fine and save a load of money on a part that no-one sees anyway.
Darkness gone, go Darknes2, go Frozen, go Tronic

User avatar
R60BBA
Senior Member
Senior Member
Posts: 1178
Joined: Sat Sep 30, 2017 7:53 pm
Location: London, United Kingdom

Noisy Diff - pinion bearings !! advice appreciated.

Post by R60BBA » Tue Feb 19, 2019 10:57 pm

Private sale or dealership?

If latter take it back, if former opt for a reconditioned diff (you could probably pick one up for £400).

You touched upon it yourself, but can you really justify spending 25% of the value of your new car on a brand new diff?
Image

Used to own the above.

Now I drive an E46 M3 Coupe:
  • Engine: S54B32
  • Colour: Carbon Schwarz
See more here: https://forums.m3cutters.co.uk/threads/ ... ck.202911/

Instagram: bavarianjunkie
https://youtu.be/y0ymv8jOC0Y

User avatar
sure2drive
Member
Member
Posts: 85
Joined: Sat Oct 27, 2018 2:57 pm
Location: New Forest, Hampshire

Noisy Diff - pinion bearings !! advice appreciated.

Post by sure2drive » Fri Mar 01, 2019 2:43 pm

Really sorry for delay in replying. I bought from an independent smallish dealer, and after checking with legal advice I do have 30 right of rejection if there is a fault, and after a bit of tooing and froing the dealer agreed there was. He offerred a full refund or said he would get it rebuilt by a decent automotive gearbox specialist (which I checked out) and give me a copy of the invoice for the 12 month warranty on the rebuild.( £450 plus VAT for all 4 bearings plus removal and re-fit.) That was agreed on Monday so it is with the dealer for this to be done. The rest of the car seems good as I have already had it checked locally which is when the fault was found, and I do like it, so fingers crossed the dealer who is the seller is as good as his word and I get it back soon.
So thanks for the help, I had no idea I had 30 right of rejection from a dealer so that was very helpful. My legal advisors have also been very good, so that helps when you have a difficult situation like this because I really liked the car and when I discovered this noise it really upset me because I thought I was lumbererd with it. I think if I ever buy a second hand vehicle again I will have it checked by an approved mechanic before I part with my cash, but luckily in this case it seems to be working out ok. Hopefully all will be well and in the meantime thanks again :)
If you want to give God a good laugh,...tell him your plans.

User avatar
sure2drive
Member
Member
Posts: 85
Joined: Sat Oct 27, 2018 2:57 pm
Location: New Forest, Hampshire

Noisy Diff - pinion bearings !! UPDATE.

Post by sure2drive » Mon Mar 18, 2019 6:59 pm

Well the dealer sent the diff away for new bearings, and re-fitted it. I spoke to the repairer (gearbox and diff specialist) the bearings were pitted and worn, but he had seen far worse. I took it back to my indy BMW garage who said that they were much quiter and fine, so all should be fine with the diff.
I feel the noise is better, but I am still hearing a fairly high pitched vibration type noise at speeds of around 25 upwards. I can't figure out what it is so I'll do some more research to see if I can at least know where to look and if necessary maybe start another post for help, but at least a big step forward :-) :)
If you want to give God a good laugh,...tell him your plans.

User avatar
wonkydonkey
Member
Member
Posts: 861
Joined: Sat May 05, 2018 9:35 pm
Location: Somerset

Noisy Diff - pinion bearings !! UPDATE.

Post by wonkydonkey » Mon Mar 18, 2019 7:14 pm

It's nice to see gratitude from people who have received help and advice :) I'm glad you reached a solution that seems entirely fair (and the bonus of a 12 month warranty!). The dealer definitely did the right thing here, so fair play to them. Let's hope this other sound is nothing to worry about :driving: Enjoy the car!
2003 3.0i E85 Z4 Roadster in Sterling Grey | E46 M3 seats | Gaptech | Stubby and proud!
<My name is James>

User avatar
maxman
Senior Member
Senior Member
Posts: 2100
Joined: Mon Jun 07, 2010 11:34 pm
Location: Wrexham

Noisy Diff - pinion bearings !! UPDATE.

Post by maxman » Mon Mar 18, 2019 9:29 pm

You could do with a z4 owner going for a ride with you to see if the noise is normal,there is tyre/road noise with the z4 roadster
Gone to a new home 2005 3.0I Toledo Blue ,Aeroskirts,Gaptech,Z4M wheels Goodyear F1 ,ZHP,M steering wheel,M front bumper.M Seats

Online
User avatar
GuidoK
Senior Member
Senior Member
Posts: 2825
Joined: Tue Aug 17, 2010 1:37 am

Noisy Diff - pinion bearings !! UPDATE.

Post by GuidoK » Mon Mar 18, 2019 11:29 pm

Finding a noise source can be extremely difficult and a LOT of work.
I mean the diff is one possible source, but tyres, gearbox or propshaft bearing..... all related to speed/engine rpm and can sound like coming from the back.
My go to instrument is the engine stethoscope. But to listen to the propshaft bearing, it has to be set up rolling on a ramp (idling maybe in 3rd or 4th), remove the exhaust and heatshielding to get to the bearing, and maybe install the exhaust again to hear the bearing above the noise....
Thats 2 hours of work alone depending on the state of your exhaust.

Still its strange that I read loads of diff problems on this forum where it doesnt seem as much of a problem on the mainland forums. :scratchhead:
The bmw diffs are usually quite bulletproof and usually only get potential problems on very high mileage (above 200k miles)
(although the 2.0i has I believe a smaller diff than the other models)
Z4 3.0i | ESS TS2+ | Quaife ATB LSD | Brembo/BMW performance BBK front/rear | Schrick FI cams | Schmiedmann headers+cats | fully polybushed | Vibra-technics engine mounts | H&R anti rollbars | KW V3 coilovers | Sachs Race Engineering clutch

grumps
Member
Member
Posts: 91
Joined: Tue Jul 02, 2013 5:07 pm
Location: Bridge of Weir

Noisy Diff - pinion bearings !! UPDATE.

Post by grumps » Tue Mar 19, 2019 12:20 am

GuidoK wrote:
Mon Mar 18, 2019 11:29 pm
I mean the diff is one possible source, but tyres, gearbox or propshaft bearing..... all related to speed/engine rpm and can sound like coming from the back.
I second that. My E86 sounded completely different underway when I put a set of winter wheels on. I'd convinced myself that I had a problem with the diff up until that point because the noise seemed to be coming from the back and it was related to road speed.
Start the day with a smile, get it over with.

Bog standard 2007 3.0si manual E86 in Montego blue with black leather, currently fitted with MV2s

User avatar
sure2drive
Member
Member
Posts: 85
Joined: Sat Oct 27, 2018 2:57 pm
Location: New Forest, Hampshire

Noisy Diff - pinion bearings !! UPDATE.

Post by sure2drive » Tue Mar 19, 2019 10:51 am

Thanks for the comments, I know it is going to be difficult. Maybe it's just me and I am looking for problems where there are none, but at the moment it really is getting me down.
I was thinking the same thing as Maxman, I should find a Z4 owner near me who would take a ride with me and see if they noticed the same noise as me. I will see if I can find a local group, meantime, anyone near West side of Southampton who is willing to meet up please PM me?
Thanks again. :thumbsup:
If you want to give God a good laugh,...tell him your plans.

User avatar
Greg 01
Member
Member
Posts: 359
Joined: Sat Apr 23, 2016 7:40 am
Location: Manchester

Noisy Diff - pinion bearings !! UPDATE.

Post by Greg 01 » Tue Mar 19, 2019 12:17 pm

Hi sure2 .
I also have had a noise on my car for about the last 3 years about 25mph and over never gotten any worse or any louder over that period of time .
I've spent well over £700 In parts and labour tryng to find it but eventually found it to be the rear tyres .
I have even gotten in the boot and had my wife drive the car while I listened .
I've found the noise does change slightly as the tyres wear . I've just put it down to being sat almost on the rear wheels and being a z4 quirk . :thumbsup:
Nachtblau metallic 3.0 si auto ,cup holders , whippy back on :thumbsup:

Online
User avatar
Pbondar
Member
Member
Posts: 852
Joined: Thu Feb 23, 2017 10:37 am
Location: Scottish Borders

Noisy Diff - pinion bearings !! UPDATE.

Post by Pbondar » Tue Mar 19, 2019 1:35 pm

I have even gotten in the boot and had my wife drive the car while I listened .


Sad bunny! :rofl: :thumbsup:
2012 E89 20i MSport Auto Atacama Yellow Changes (Wheels/Tyres/Spoiler/Steering Wheel/Shock Absorbers/ARB/Diff/Diffuser/Brakes) Upcoming changes (Speakers) Full Whippy here!

Image

User avatar
sure2drive
Member
Member
Posts: 85
Joined: Sat Oct 27, 2018 2:57 pm
Location: New Forest, Hampshire

Noisy Diff - pinion bearings !! UPDATE.

Post by sure2drive » Tue Mar 19, 2019 2:53 pm

Thanks, I think that helps ?? :cry: At least I am not alone in this.
I can't say it's related to any of the runningrear really. It is a pretty constant noise, not loud but the frequency grates with me, it doesn't seem to increase with speed, stays the same when freewheeling , even gentle breaking. Sounds a bit like a fairly high frequency vibration, maybe whistling in a metallic sounding way?? wow trying to describe an irritating noise is really difficult!!.
I have stuffed the boot with a rubber mat and some old pillows and quilts to try and deaden the noise but that hasn't helped.
It just gets in my head and if I can't either establish it as "normal" or find the cause I may even have to sell it!
Recently regarding the Brexit vote they defined madness as doing the same thing over and over and expecting a different outcome, that's a bit like me at the moment. I keep wanting to take it for a drive to see if the noise has gone, and of course it hasn't.
I hope to find another owner not too far away just to have another opinon on weather I really am mad or not :)
Don't be put off though, I am not really mad, just want a second opinion without bothering my dealer again. :dizzy:
If you want to give God a good laugh,...tell him your plans.

User avatar
Greg 01
Member
Member
Posts: 359
Joined: Sat Apr 23, 2016 7:40 am
Location: Manchester

Noisy Diff - pinion bearings !! UPDATE.

Post by Greg 01 » Tue Mar 19, 2019 3:29 pm

I know how you feel sure2 .
I had trouble defining what I was hearing . Had diff checked wheel bearings done blocked the drain holes up in case it was coming up the tube drove me nuts for awhile .
I stripped the boot and put sound deadening in all the places I could .
I found by accident a really smooth bit of tarmac on the m6 jct 19 and the noise was gone the tarmac had just been laid and I did a few passes and yes it was the rear tyres . :rofl: :driving:
Nachtblau metallic 3.0 si auto ,cup holders , whippy back on :thumbsup:

Post Reply