Click here to return to the home page.
Classic Morgans
Who's Online Now
10 registered members (RichardV6, M3W55, Paul Grout, petemog, brownbaker, Jens, Max5, yrr13, CPN, CLPlusFour), 173 guests, and 12 spiders.
Key: Admin, Global Mod, Mod
Top Posters(30 Days)
John V6 195
+8Rich 138
Alistair 136
OZ 4/4 125
Image 96
Newest Members
05 Roadster, John Tromans, Factotum, Dave Jones, Fester
8159 Registered Users
Newest Topics
A great day out
by Gambalunga. 27/11/22 11:45 AM
New Zealand
by Paul Grout. 26/11/22 08:02 PM
RIP Doddie Weir
by +8Rich. 26/11/22 06:04 PM
Why is everything hard work these days?
by Paul F. 26/11/22 03:43 PM
Extra Gauges Plus 4 GDI
by DaveW. 26/11/22 03:18 PM
Old School scam
by lowebird. 26/11/22 11:03 AM
VSCC Prescott vid
by Luddite. 25/11/22 06:10 PM
Latest Photos
Under the clouds....
Ms Marple's island/s connection...
Autumn Sunshine
Back Onshore
Citroens in Amsterdam
Forum Statistics
Forums34
Topics44,350
Posts749,243
Members8,159
Most Online1,033
Dec 28th, 2019
Today's Birthdays
No Birthdays
Previous Thread
Next Thread
Print Thread
Page 1 of 4 1 2 3 4
diff noise #757374
06/10/22 07:41 AM
06/10/22 07:41 AM
Joined: Aug 2022
Posts: 5
G
GrantAnderson Offline OP
New to Talk Morgan
GrantAnderson  Offline OP
New to Talk Morgan
G

Joined: Aug 2022
Posts: 5
Hi,4/4 Sport 2009 strange noise at speed.I suspect a problem with the diff which I have been led to believe is a lsd.On throttle(drivetrain under load)there is no noise,let the throttle off(again drivetrain under load)no noise,on a very light throttle(cruising at 65/70)the noise from the diff is a loud wailing sound,sounds like metal on metal or tractor tyres at speed on a tarmac road!Apply a little throttle and it immediately goes,as does completely lifting off.Any journey at motorway speeds is a real pain.This is my sixth Morgan and the only one to sound like this.Mrs Anderson is not impressed.Your thoughts would be greatly appreciated.I have tried new diff oil with a friction modifier but this has made no difference.

Re: diff noise [Re: GrantAnderson] #757380
06/10/22 08:18 AM
06/10/22 08:18 AM
Joined: Jul 2007
Posts: 23,165
Suffolk, England
John V6 Offline
Brooklands Register contact
John V6  Offline
Brooklands Register contact
Member of the Inner Circle

Joined: Jul 2007
Posts: 23,165
Suffolk, England
When did you last change / check the oil level. LSDs need oil with a special friction modifier. I would change the oil as a first step.

Some advice here in GoMog and in Dave's how to section under Roadster servicing


JohnV6
2014 Brooklands Edition Roadster "Brookland's Belle" #5 of 50
Re: diff noise [Re: GrantAnderson] #757381
06/10/22 08:23 AM
06/10/22 08:23 AM
Joined: Feb 2016
Posts: 5,463
East Harling, Norfolk UK
RichardV6 Online NoMood
Charter Member
RichardV6  Online NoMood
Charter Member

Joined: Feb 2016
Posts: 5,463
East Harling, Norfolk UK
If it happens in a straight line I doubt the LSD is to blame (if you jack up rear of car and one wheel turns the other you have a LSD). As oil change has made no difference a strip down is maybe needed which should reveal issue. Thoughts are poor pinion support/mesh with crown wheel.


Richard

2018 Roadster - Red/Magnolia - "Morton"
1966 Land Rover series 2a SWB
1945 Moto Guzzi Airone
Re: diff noise [Re: GrantAnderson] #757394
06/10/22 10:57 AM
06/10/22 10:57 AM
Joined: Sep 2014
Posts: 2,161
London
MOG 615 Offline
Talk Morgan Expert
MOG 615  Offline
Talk Morgan Expert

Joined: Sep 2014
Posts: 2,161
London
Without listening to the noise it is difficult to diagnose. Richard is probably correct if that is indeed the source.

Just to throw in a curved ball, is it possible that does not come from inside the diff at all, and is could be due to other issues .The fact that the noise is different power on/power off makes me wonder if the diff (or some other part of the rear axle) is hitting the transmission tunnel (or the top "shelf"?) under power. This will result in a very metallic whirr which will probably be speed dependent. However this theory does not fit the fact that the noise is prevalent on a light throttle.

Have you checked that the exhaust system does not contact the chassis , or bodywork at any point ? Clutching at straws here I admit .

The 4/4 Sport is a wonderful car, in many ways truer to historic Morgan DNA than any post 2000 model, and I am sure this can be sorted.


Andy G
1999 +8 , Indigo Blue.
Ex-John McKecknie/Mike Duncan 1955 +4 racer.
Re: diff noise [Re: GrantAnderson] #757400
06/10/22 11:58 AM
06/10/22 11:58 AM
Joined: Sep 2009
Posts: 6,451
Köln Germany
Heinz Offline
Talk Morgan Sage
Heinz  Offline
Talk Morgan Sage

Joined: Sep 2009
Posts: 6,451
Köln Germany
To give some consolation, should it be a problem with the diff, and assuming you are a spirited sporty driver, then it would be an opportunity to upgrade to a 4.1 final drive if you had to pay for the repair anyway. I would love to do it, but my BTR diff won't allow a change. Your 2009 Salisbury axle does though.


'14 4/4 graphite grey
Re: diff noise [Re: GrantAnderson] #757407
06/10/22 12:56 PM
06/10/22 12:56 PM
Joined: May 2014
Posts: 4,238
Essex
Burgundymog Offline
Black Rat
Burgundymog  Offline
Black Rat
Part of the Furniture

Joined: May 2014
Posts: 4,238
Essex
Have you checked for play in the wheel bearings ?


Keith
2013 narrow bodied + 4 Ruby.
Re: diff noise [Re: GrantAnderson] #757410
06/10/22 01:21 PM
06/10/22 01:21 PM
Joined: Jul 2007
Posts: 23,165
Suffolk, England
John V6 Offline
Brooklands Register contact
John V6  Offline
Brooklands Register contact
Member of the Inner Circle

Joined: Jul 2007
Posts: 23,165
Suffolk, England
Check the rear suspension where the brackets fit onto the wheel drum. They can shear off


JohnV6
2014 Brooklands Edition Roadster "Brookland's Belle" #5 of 50
Re: diff noise [Re: GrantAnderson] #757432
06/10/22 05:10 PM
06/10/22 05:10 PM
Joined: Nov 2015
Posts: 5,445
Northern Capital of Cool
CooperMan Offline
Just barreling along
CooperMan  Offline
Just barreling along
Charter Member

Joined: Nov 2015
Posts: 5,445
Northern Capital of Cool
4/4's don't have an LSD as standard, unless the Sport spec was different ?

Sounds like the drivetrain rubbing on something, check for play in the UJ's, is the handbrake outer catching on a propshaft flange, also look at the engine mounts if the rubbers gone off in one side it will shift as described with power on / off

Last edited by CooperMan; 06/10/22 05:16 PM.

Jon M
Re: diff noise [Re: CooperMan] #757433
06/10/22 05:12 PM
06/10/22 05:12 PM
Joined: Dec 2009
Posts: 31,505
Devonshire
+8Rich Offline
Tricky Dicky
+8Rich  Offline
Tricky Dicky
Member of the Inner Circle

Joined: Dec 2009
Posts: 31,505
Devonshire
No the Sport was conventional diff - I had one from new in 2009.

This one could have been interfered with of course..


Regards Richard

1999 Indigo Blue +8
2009 4/4 Sport Green prev
1993 Connaught Green +8 prev





Re: diff noise [Re: GrantAnderson] #757460
06/10/22 07:00 PM
06/10/22 07:00 PM
Joined: Dec 2008
Posts: 20,617
South Yorkshire
DaveW Offline
Roadster Guru
DaveW  Offline
Roadster Guru
Member of the Inner Circle

Joined: Dec 2008
Posts: 20,617
South Yorkshire
Some pinions have a preload with a collapsible spacer behind the drive flange. I'm not sure if the BTR axle is like this, but I would drop the rear of the propshaft, and check the tightness of the pinion nut. Don't Tarzan it. Just a gentle nip with a ring spanner so you can see if it turns. If it has loosened, a blob of loctite should hold it.

Before doing that, the Sport doesn't usually have a tool tray, and the ply cover may be glued down, but I would remove the cover, and go for a drive with the roof up, and a passenger who can lean over and do a visual on the rear end.


DaveW
'05 Red Roadster S1
'16 Yellow (Not the only) Narrow AR GDI Plus 4
Page 1 of 4 1 2 3 4

Moderated by  TalkMorgan 

Powered by UBB.threads™ PHP Forum Software 7.7.1