Morris Minor Owners Club

Can someone advise please. Since we have had our 65 convertible nearly a year ago she has had vibration coming from the rear end - reminds me of a spin dryer on the overun and occurs over 50mph. It is related to road speed not engine or gearbox speed. Also leaks oil from the halfshaft joint with the flange - not the halfshaft oil seal. Work to remedy includes:

1. balanced all wheels then swapped wheels with friend - no change with either, tyres are fairly new.
2. changed uj's - a lot worse, started at 30mph
3. balanced propshaft after new uj's - slightly better
4. changed propshaft - quite a lot better
5. changed gearbox - quieter ride but no change at axle
6. changed diff - got rid of axle rumble but not vibration
7. new rear shockers and springs, rides better but same vibration
8. new wheel bearings, no change
9. poly bushes all round (hangers are solid), no change
10. new brake drums, no change

Considering changing half shaft and stub axle but they look ok, I wonder if she has had a shunt or the whole axle casing is slightly skew whiff. Car is beautiful otherwise.

Advice/solutions/offers of sympathy greatly appreciated

Have you checked to see if the tyres are the same width and aspect ratio?

You've certainly done all the normal possibilities!
Personally I'd be tempted to just try another complete axle assembly but if it was me I'd probably leave the car for a few years until i'd got my patience back!!!

Hello Southerly,

you have covered just about everything. I would discount the half shafts as they are such a small relative diameter and are unlikely to be the source of vibration.
One thing worth checking is to jack the car up and spin the wheels to check for true running. As you mention a rear hub leak, it's possible that one rear wheel may have been badly kerbed and distorted the hub.

Alec

Probaby a last resort, have you checked that the tyres are OK?

Some time ago I havd a really bad problem with a Metro - after all the usual checks, I eventually discovered one of the new(ish) tyres had developed a bump on the tread.....

You can check this at the same time as the vertical "wobble).

Cheers.

Colin

Did you change the whole differential including the pinion flange or just the crown wheel and pinion? I have had experience of the diff units pinion flange being bent!! This caused bad vibration from just below
50 mph. You say you changed the Prop Shaft with good results, did you then have the new one balanced etc. and have you checked the rear prop shaft flange for true running, it only has to be slightly bent to ruin the ride.

Unlikely I know but I had a similar problem recently and my Traveller is fitted with Anti Tramp / Rear Radius arms between the axle housing and the rear floor and it turned out to be the bushes in the bars were completely worn out giving a metal to metal contact the noise was mainly heard on overun at 40 - 50 mph on removal of the bars the problem has dissapeared, but if you dont have them fitted this suggestion wont help much.