As I've got a 1,800 mile round trip with a big trailer next weekend, figured I'd give the car a 10,000 mile service (it was only 300 miles short of one anyway) today. While underneath draining the oil and greasing the propshaft UJs, I noticed this

Not noticed it before and no idea how long it has been like it, although it must have been OK at the last MoT, although that was in August last year. A quick call to my local motor factors who seem to stock just about everything, and picked up a new one half an hour later (not too bad at £16). The car feels slightly different on the 160 degree adverse camber corner into the village but other than that, it doesn't drive any differently. So why do we have anti-roll bars in the first place?

The drop links keep the anti roll bar semi rigid on the ends, there meant to keep both the wheels at the same level in theory, ie, if one wheel lifts or drops, it’s meant to make the other follow the same route, although not exactly, ( as near as ).
I’m not surprised you didn’t notice it, I think our EAS does such a good job that the anti roll bar doesn’t get to much of a hammering unlike some cars

I know what they are supposed to do, I'm just surprised I hadn't noticed it when it first went, whenever that was. It must be down to the EAS doing such a good job as on anything else you'd notice it wallowing around all over the place. The only thing I can think of that was similar was many years ago I had a Citroen DS with the hydropneumatic suspension and drove around with a totally flat rear tyre. I didn't notice anythig until I reversed into a parking space and could hear a strange noise.

I suspect those 4 big bushes in the front radius arms get involved in the anti roll business. With the axle connecting the radius arms any roll means that one side of the bushes needs to squidge and the other side stretch. Which doesn't really happen with solid rubber so the whole thing has to distort and shift too. Between the 4 bushes there is a lot of solid rubber involved.

Probably more of a speed related effect anyway. Sharp inputs at high speed being more likely to invoke things that more normal driving. Big squidgy tyres probably cushion any steering / handling effects too. For my money its more about controlling the body movement than steering / handling although with the steering box on the car and drag link connection there is some (theoretical) potential for roll steer.

Scary thing on a P38 is how little there is actually connecting the body to the axles with any degree of rigidity. Just a panhard rod and rubber bits at the ends of the radius arms.

Clive.

Which might explain why the radius arm bushes need replacing at 120k (in my case)!

Did my big radius arm bushes, and the rear rubber lumps, back last summer at around 89,000 miles and 18 years. Objectively a bit early judging by the general condition of the removed bushes but produced a noticeable improvement in all forms of stability including roll. Wasn't bad before but clearly getting older. In my neck of the woods there are some horrible more or less straight longitudinal dips and weaves in the road surface that really bite when it comes to straight line stability, roll steer, bump steer et al. Not purely a Rangie effect. Everything suffers.

Starting to feel things a bit again so Panhard Rod bushes on this summers job list. Which makes pretty much all change for the front end over the last 10,000 or so miles. Mimbling over the steering damper.

Clive

If you detach the roll bar links, axle articulation is incredible when driving off road.
I bought some stainless steel rose joints and other bits, with the intention of making the links easily detachable by just removing a couple of pins.
Someone on RR.net said they also did it with rose joints and the noise and vibration was awful so I put it on hold.
I did see a system that used rubber bushes and was detachable.

Quick disconnects for the roll bars are very common in the Jeep world, you might have a look at them for inspiration?
https://www.quadratec.com/vehicle/1984-2001-cherokee-xj/lift-kits-and-suspension/sway-bar/quick-disconnect-end-links for example

One of mine broke 2 weeks ago and I definitely noticed it weaved a lot more on the M56 at 70mph.

I got a replacement from LandRanger (made in India) and it was the wrong size. The thread was only 20mm long not 30mm. Came with nuts though. The replacement that was 30mm DIDN'T come with nuts - check :-D