Morris Minor Owners Club

I always thought the higher the diff ratio the more chance of breaking one. So a 3.9 would have a lower chance than a 4.2.

Using this logic lcvs are very prone. They have a very low ratio, and when empty are very light at the back so can bounce promoting wheel slip.

Reviving an old thread, I wonder if n/s shafts break more frequently because in the UK we drive on the left, and that tends to be where potholes and rougher road surfaces generally tend to be?

Does fitting radius arms to the back axle reduce the likelihood of half shaft failure?

Fitting traction control (anti-tramp) bars to the rear axle does eliminate the hop and skip of the Minor axle. The hop is alright but when the axle comes back to earth and the tyre contacts the road surface the sudden shock can cause the axle shaft to shear. The once or twice may be ok but regular hoping of the axle is a recipe for disaster/damage.
I could not run my Minor without the traction control (anti-tramp) bars. Some form of traction control (anti-tramp) restrictors have been fitted to my Minor since the early 1970s. The rose jointed traction control (anti tramp) bars fitted to my Minor are home made and have been on the car since the early 1980s as back then nothing was available off the shelf.
If you have a moderately powerful engine i.e. 1275cc engine I would recommend fitting a set of traction control bars. They are available from ESM as a bolt on kit https://www.morrisminorspares.com/rear- ... up-p831360. The traction control (anti-tramp) bars are much cheaper than upgraded axle shafts.
Also available from JLH but some welding required.
https://www.jlhmorrisminors.co.uk/suspe ... m-kit.html

Both times I've had a half shaft break it has been the n/s and at very low speed just after moving off from a stand.
I think I'll look into radius arms, ESM do sell them.

After searching the ESM web site I did eventually find the anti-tramp bars. The front attachment of the bars is very similar to that fitted to my Minor.
It is the sudden shock to the axle shaft that causes their demise. That shock can be brought on by various causes but wheel hop is the main one.

philthehill wrote: ↑Mon Aug 04, 2025 9:42 pm After searching the ESM web site I did eventually find the anti-tramp bars. The front attachment of the bars is very similar to that fitted to my Minor.
It is the sudden shock to the axle shaft that causes their demise. That shock can be brought on by various causes but wheel hop is the main one.

Link to ESM kit. I assume they bolt between the spring u-bolts and the plates that locate on the transmission tunnel.

https://www.morrisminorspares.com/rear- ... up-p831360

(Note to mods: this is not an endorsement, just for information)

The rear end of the ESM kit bolts under the rear axle spring 'U' bolts and the flat plates bolt either side of the rear spring front mount.

I made my anti-tramp-bars myself and used the ESM-fitting plates. But I used rose joints to hold the axle precisely not by rubber bushes. Addidionally I fitted adjustable SPAX dampers.
That in all was a real improvement as the springs don’t have to guide the axle which is mainly done by the a/t-bars now.

Chris

What ever you do to control the axle I would recommend that you ditch the rubber pads either side of the spring and fit as a minimum poly pads.
If you want to go the whole hog - replace the rubber or poly pads with solid spacers as per the van/pickup.
Way back I used to control axle tramp and spring wind up by fitting additional clamps to the spring and tightening the clamps to suit.
My own anti tramp bars are fully home made with R/H & L/H rose joints because way back then there were no ready made antitramp bars for the Minor. Additionally I fitted a rear tele dampers kit from Ledbetter's of Lancashire which used the classic Mini front damper. I still use the classic Mini front damper but have upgraded to gas dampers with revised mountings. The ESM front mount for the anti tramp bar are similar to that fitted to my Minor with the ESM ones being thin plate with a raised and rolled edge. My plates are flat.

philthehill wrote: ↑Sat Aug 30, 2025 4:43 pm What ever you do to control the axle I would recommend that you ditch the rubber pads either side of the spring and fit as a minimum poly pads.
If you want to go the whole hog - replace the rubber or poly pads with solid spacers as per the van/pickup.
Way back I used to control axle tramp and spring wind up by fitting additional clamps to the spring and tightening the clamps to suit.
My own anti tramp bars are fully home made with R/H & L/H rose joints because way back then there were no ready made antitramp bars for the Minor. Additionally I fitted a tele dampers kit from Ledbetter's of Lancashire which used the classic Mini front damper. I still use the classic Mini front damper but have upgraded to gas dampers with revised mountings.

Interesting comments re the rubber pads. I've just renewed mine in rubber, always thought the back axle being fairly stiff could use a little more compliance in it. Do poly pads locate the axle better?

Poly pads do locate the axle better.
I have now gone the whole hog and fitted solid spacers similar to those fitted to the van/pickup for absolute positive axle location.