Disco 2 Replacing the rear suspension air bags.

Being a bit long in the tooth, like what I am, I put the Disco into the local indie garage for them to change the "windy-springs", rather than me scrambling about underneath to do the job.
It was a good thing I did, when they took the old bags off they were confronted by some rot holes behind the bags which under normal conditions would remain unseen, hidden behind them.
They have been able to weld plates and repair the damage, so all is good again, and quite fortuitous that the garage were able to catch the trouble before it went too far.

Ouch! Two good jobs sorted there.

Feathers McGraw said:

Ouch! Two good jobs sorted there.

Click to expand...

Ouch is right, but it had to be done and I'm in no position to even think about welding that sort of job. Apart from not being able to lift the vehicle high enough, I don't even posess any suitable kit.
At least it was caught before it went too far.

After reading the paperwork from the garage, apparently they took a look at the rest of the "underworld" while they had the Disco up on the ramp and they have advised me that the little rubber boots on the bottom steering knuckle ball joints are beginning to perish and deteriorate, so it looks like a bit of a repair/rebuild in that area could be in order sometime in the not so distant future.
Being a "pressed in" unit, and since I don't have the kit to do the job, it looks like another trip to the garage.

brian47 said:

After reading the paperwork from the garage, apparently they took a look at the rest of the "underworld" while they had the Disco up on the ramp and they have advised me that the little rubber boots on the bottom steering knuckle ball joints are beginning to perish and deteriorate, so it looks like a bit of a repair/rebuild in that area could be in order sometime in the not so distant future.
Being a "pressed in" unit, and since I don't have the kit to do the job, it looks like another trip to the garage.

Click to expand...

i do quite a few,bottom ball joints are likely worn but its worth doing the tops a well, ensure they have suitable pullers as a few garages like to use heat and a hammer, usually need over 20 ton force to shift them

20 tons to loosen the tapers? Ten times the weight of the car. That seems high.

brianconwy said:

20 tons to loosen the tapers? Ten times the weight of the car. That seems high.

Click to expand...

20 tons to release the joints,

brianconwy said:

20 tons to loosen the tapers? Ten times the weight of the car. That seems high.

Click to expand...

The tapers aren't the problem, they can usually be cracked with a couple of hammers or an ordinary ball joint splitter. The problem is the ball joint unit is pressed into the front axle casing and they need some serious steady force to push them out and push the new ones into place.

jamesmartin said:

i do quite a few,bottom ball joints are likely worn but its worth doing the tops a well, ensure they have suitable pullers as a few garages like to use heat and a hammer, usually need over 20 ton force to shift them

Click to expand...

I fully intend to replace the top joints as well as the bottom ones and while everything is pulled to bits, it might be a good idea to change the CV joints at the same time.

It looks like they have been machined from bar on a lathe, rather than from a forging. Wouldn't the design make it easier for replacement if the joint was held in place with nuts and bolts. It might make them dearer to produce though. But I suppose the vehicles are aimed at rich people who have their work done at main dealers rather then the likes of us.

changing my bags next week will have a look at the chassis behind them while the bags are out glad i read this now,

brianconwy said:

It looks like they have been machined from bar on a lathe, rather than from a forging. Wouldn't the design make it easier for replacement if the joint was held in place with nuts and bolts. It might make them dearer to produce though. But I suppose the vehicles are aimed at rich people who have their work done at main dealers rather then the likes of us.

Click to expand...

Press fitting of such components is an accepted method these days by many manufacturers. According to LR, the top and bottom ball joints on the Disco should only be replaced three times before the whole front axle case which houses them has to be replaced as well due to the mounting hole becoming distorted and therefore too large because of the forces required to fit them.

brianconwy said:

It looks like they have been machined from bar on a lathe, rather than from a forging. Wouldn't the design make it easier for replacement if the joint was held in place with nuts and bolts. It might make them dearer to produce though. But I suppose the vehicles are aimed at rich people who have their work done at main dealers rather then the likes of us.

Click to expand...

axle yoke is a forging, pressing is cheap and exact in positioning theres a lot of force on the joints, they would have to be a good dowel fit at least if secured by bolting

Most suspension joints use forgings and are bolted in place. Forgings will work out more expensive and need to be loaded into a lathe manually whereas these are likely to be machined from steel bar which is automatically fed into the lathe. There is an obvious cost advantage. I have never heard of problems from steering joints that are due to being bolted into place.

brianconwy said:

Most suspension joints use forgings and are bolted in place. Forgings will work out more expensive and need to be loaded into a lathe manually whereas these are likely to be machined from steel bar which is automatically fed into the lathe. There is an obvious cost advantage. I have never heard of problems from steering joints that are due to being bolted into place.

Click to expand...

That's all a bit academic really, LR aren't going to change the design now and then recall all the Disco 2's left on the road to install the replacement ball joints.

No and nobody has suggested they would. But there are plenty of design choices that have to be worked around. There were also design faults that had to be worked around in production of parts. One water pump had a machined outside diameter that was a push fit into the bracket. The problem is that the 'chimney' was supported by webs but where the drain holes were there were no webs. When the bearing was pressed in the chimney expanded at these unsuported points and caused ovality. Not a lot but cenogh for the assemblers to use copper mallets to hammer the pump in. I bet it was fun removing them years down the line. Iwas only commenting on design choices.