81 320i howling rear end

For all your questions, problems and DIY stories
Post Reply
e21loraine
Newbee
Posts: 4
Joined: Sat Mar 22, 2014 7:53 pm
My E21(s): 81 us 320i manual

81 320i howling rear end

Post by e21loraine »

Hey guys I'm new to the forum and would like some help. I have two problems.
1-Howling in the rear
2-transmission whining in 1,2,3,and 5th gears never in 4th.
recently my car started to howl when I have no load on it, such as when I'm driving and let off the gas it starts to howl or whenever I press in the clutch , its not a continuous howl but on off on off as if something rotating and making it howl, its coming from the right side In the rear., this happened after I ran over an unexpected large pothole , any help would be greatly appreciated.

Now with my transmission, it whines through all gears but fourth, its a constant whine that goes away when I have no load on it, such as letting go of the gas as soon as I press it the whine comes back, its been bugging me for half a year now
Any help or insight would be greatly appreciated , thanks in advance!


User avatar
e21-Mark
E21 Master
Posts: 5715
Joined: Fri Mar 21, 2008 2:19 pm
My E21(s): 316 m52/2.8 Cat Cams & Jenvey ITB
Facebook page: https://www.facebook.com/JackyardBackoff
Location: Cornwall - UK

Re: 81 320i howling rear end

Post by e21-Mark »

Whatever it is, it sounds like you need to change the gearbox.
pandemonium001
E21 Pro
Posts: 528
Joined: Sun Oct 07, 2012 1:19 pm
My E21(s): E12 535i T (ish)
Location: Scotland Ayrshire

Re: 81 320i howling rear end

Post by pandemonium001 »

Gearbox will probably be the lay shaft bearings, 4th is commonly direct 1:1 drive to the output shaft so not running the defective bearings, but I could be wrong, easier just to swap it out.
rear wheel bearing?.
check your tyres I had a type r with toyo proxies fitted, they where wearing uneavenly, every other tread block causing a horrible rumble like a wheel bearing, swapped for dunlop problem solved.
User avatar
Jeroen
Site Admin
Posts: 29994
Joined: Tue Sep 14, 2004 12:23 pm
My E21(s): '81 323i Baur
Location: The Netherlands
Contact:

Re: 81 320i howling rear end

Post by Jeroen »

Right oil & correct level in gearbox and diff? Jack up the rear to check the wheel bearings, and indeed, bad tyres can cause the same noise as a bad bearing!
Regards/groeten, Jeroen
e21loraine
Newbee
Posts: 4
Joined: Sat Mar 22, 2014 7:53 pm
My E21(s): 81 us 320i manual

Re: 81 320i howling rear end

Post by e21loraine »

Thanks for the input guys, Tranny should be good on fluids , I filled it when I swapped clutch, I've been a bit suspicious of the diff being low, I should check it out, how would I check the wheel bearings?
User avatar
Jeroen
Site Admin
Posts: 29994
Joined: Tue Sep 14, 2004 12:23 pm
My E21(s): '81 323i Baur
Location: The Netherlands
Contact:

Re: 81 320i howling rear end

Post by Jeroen »

Jack up the rear, for example under the diff, make sure the wheels are off the ground. If you spin a wheel you should hear the bearing. Easier for the front as with the rear half the driveline spins along but ok. Another test could be to try a different set of wheels at the back, see if that resolves your issue.
Regards/groeten, Jeroen
pandemonium001
E21 Pro
Posts: 528
Joined: Sun Oct 07, 2012 1:19 pm
My E21(s): E12 535i T (ish)
Location: Scotland Ayrshire

Re: 81 320i howling rear end

Post by pandemonium001 »

As above jack up, both hands at 3 and 9 o clock rock side to side can you feal any clunks or movements?
repeat hands at 12 and 6.
e21loraine
Newbee
Posts: 4
Joined: Sat Mar 22, 2014 7:53 pm
My E21(s): 81 us 320i manual

Re: 81 320i howling rear end

Post by e21loraine »

Alright guys, I did some investigation today, the wheel moves around side to side with the car jacked up, I can wiggle it any direction, so I took off the rim and the whole drum brake is wiggling around, what would this be? The wheel bearing? Or??? Any input would be nice and greatly appreciated, thanks!
e21loraine
Newbee
Posts: 4
Joined: Sat Mar 22, 2014 7:53 pm
My E21(s): 81 us 320i manual

Re: 81 320i howling rear end

Post by e21loraine »

Does anyone have any input on it?
User avatar
TopCat
E21 Pro
Posts: 1079
Joined: Thu Apr 21, 2011 2:21 pm
My E21(s): 1980 Alpina B6 2.8
Facebook page: https://www.facebook.com/timothy.c.boles
Location: Isle of Man and Inverness
Contact:

Re: 81 320i howling rear end

Post by TopCat »

sounds like a wheel bearing! NB my lack of mech knowledge! But if it is the axle- herewith my recommendation:

I really would recommend Phil at Road and Race Transmissions for all you back axle woes/rebuilds etc

They usually do Caterham racecars- but recently started on Yanks
http://www.mycaterham.com/66828/117416.html

Road & Race Transmissions
The Bullock Shed
Filston Farm
Shoreham, Kent
TN14 5JU

tel: 01959 525105
mobile: 07836 33388

I gave him Butch's Axle 2 years ago after it had been done by someone well known in the US world (and it was making the wrong noises) he rebuilt it and confirmed that it hadn't been set up 100%

I am shortly to send him Camilla's axle
Regards
Topcat
Isle of Man Inverness
1980 BMW E21 Alpina B6 2.8
1991 BMW E30 Hartge H26
Post Reply