Thread: How did this happen?!?! Broke right front half shaft on 81' SIII 109 Military 6-pot

I think the non-standard bearing might be the problem.
The bearing with the separate inner race allows the half shaft to move. As you corner the shaft moves so that the UJ finds the centre of the turning axis.
By using a bearing that doesn't allow the shaft to float, as you corner it would have been trying to bend the shaft backwards & forwards if the UJ wasn't on the centre of the turning axis. Or it would have created heat as it tried to slide backwards & forwards through the inner race of the bearing.

Colin

As Colin says, but other possibilities are a bent axle housing giving the same results - bending the axle shaft. Probably unlikely, but some Series 3 parts have been less than up to standard. The break reminds me of one I saw many years ago on a rear axle shaft of an IH R190, that was almost certainly due to incorrect heat treatment of the shaft.

Broken front axle shafts on Series Landrovers are extremely rare (unlike rears) - I have been driving and repairing Series Landrovers for almost sixty-five years, and have never actually seen one in the flesh. Failed swivel U-joints are not uncommon (usually due to using water or mud filled swivel housings), but I have never seen one cause a broken shaft.

Have had this happen twice on the right front side so going back to my original questions to see if we can possibly figure this out. Is this due to a faulty hub bearing allowing the hub to shift which forces the half shaft to bind into the inside of spindle OR is this a balance issue due to the half shaft U-joint being installed incorrectly?!?!? After the first incident, detailed above, I ordered a new half shaft and inspected and reinstalled. Same result.

This truck is a former Australian military that was registered for service in 2/18/1981. This was a knock down kit assembled in Australian so I don’t know when the parts were actually manufactured and shipped which is relevant since there were design changes to the half shafts, drive flanges and spindles around that time.

This truck has a 24 spline half shaft and drive flange which I believe is the later design change since the earlier models had a 10 spline. But, the bearings in the hub are different sizes which should identify it as the earlier type of hub. The front left and right sides are the same in their parts. No differences.

So I’m not sure if I have a mix of parts, but I’ve put 5,000 miles on this truck and it was only when I was simply replacing the bearings, gaskets and seals in the hub/swivel/spindle(stub axel) that I started to have this occur. The first time it occurred I had installed spindles from Rovers North(PLB413) and all seemed fine during the install. The second time I used the original spindle (one with a pressed on race). Both times I put the truck on axle stands and ran it while checking the temps around the drive flanges and brake drums, etc. Both times after only a few minutes of running the right half shaft began to bind in the spindle. Prior to the test run on axle stands I spun the wheels and looked for any binding. There were no signs that anything was unusual.

I’m looking for someone who might be able to shed some light on what is going and how is this happening.

IMG_6757.jpgIMG_6756.jpg

Just a brief thought while I wait for the kettle. You say it's happened again. But it hasn't. It's happened in the same place, sure, but the two are completely different, going by the pics. The first shows a clean break, which is what they usually do ( admit I have never seen a front break ) with some evidence of heat bluing of the shaft. This time something has clearly "spun", and thus worn or in this case gouged the shaft. Without being there I'd suspect a hub bearing failure in the second case, cause unknown without seeing the installation.

It might appear to be two different types of issues but the only reason they don’t look the same is that I stopped the truck before letting it go so far that it broke the half shaft. Had I let the wheels continue spinning I have no doubt it would have eventually broken the shaft and grinded down the ends smooth just like the first set of pics.

Originally Posted by matthamilton

It might appear to be two different types of issues but the only reason they don’t look the same is that I stopped the truck before letting it go so far that it broke the half shaft. Had I let the wheels continue spinning I have no doubt it would have eventually broken the shaft and grinded down the ends smooth just like the first set of pics.

I only have the pics to go by but I can't agree with that. The first set of pics show a clean shear. Broken axles usually look like that, although often they occur at the splines. There is absolutely no sign of any rotational wear at the break. The second set shows a very obvious rotational failure, possibly a faulty bearing but also possibly a failure of lubrication. I bet if you measured the length of the first one, both pieces combined, you would find no loss of material, and so no grinding down. If the two pieces had been in contact the way you assume you would see signs of shatter. The axle material is brittle, which is why you see such clean snaps.

Happy to be proven wrong, but I spent four years as a mech in the Aus Army back in the day and have seen a few Series axle failures. Admittedly, Series IIA, but the principle is the same.

I would be checking king pin alignment do you have the correct parts installed there are several combinations of front swivel components. The photos seem to indicate a misalignment between the solid axle housing and the swivel joint. I don’t know if you have a manual you can use the link below.

Series III Workshop Manual - Land Rover Technical Blog

Originally Posted by Gippslander

I would be checking king pin alignment do you have the correct parts installed there are several combinations of front swivel components. The photos seem to indicate a misalignment between the solid axle housing and the swivel joint. I don’t know if you have a manual you can use the link below.

Series III Workshop Manual - Land Rover Technical Blog

Good point. They are different to IIA a bit. I was wondering if they had got swapped left to right or something simple like that. Not sure if that can happen on a III. 45 years since I left the Army, bit hazy on the details.

That bearing failure is epic.