Here:-

https://x8r.co.uk/products/land-rover/land...it-end-cap 2011 MY D4 HSE
Previously 2001 D2 TD5, 1996 D1 300Tdi, 1985 90 2.2 petrol.
Bikes! KTM, BMW, British, Classics and others.

Ok so finally got round to tackling this job a couple of weeks ago but wanted to run it out for a while before posting. I decided to buy a kit complete with a new alloy cap as mentioned. Couple of points that may help others: After reading about the difficulty with the push-fit connectors on the airline I sprayed plenty of WD40 over the them for several days before removal - this didn't help, still had to cut the pipes as they were seized solid. Not too much of a problem, just buy a couple of push fit connectors beforehand, only a couple of pounds. Next, the 'difficult' top bolt. I've read several posts that reference getting a socket on the bolt, but I think the easiest way is with a ratchet spanner. try to get as much room as possible by removing the rubber compressor mounts and pop the compressor out of the seating, this will give you a little more wriggle room. There is a pretty good video on youtube from PowerfulUK showing how to remove. Despite this, for me, the bolt was seized and rounded off! The kick in the teeth is that the captive nuts that the bolt goes into often rust and break easily (make sure you buy some beforehand, but this one was, unfortunately, in good shape! Luckily, I had an Irwin Grip Socket that I managed to get on there and removed the rounded bolt. Finally, I could remove the compressor and take it to the bench.

After cleaning up the externals I stripped down the drier. I had the previously mentioned crack in the lid between two ports, and the desiccant was pretty clogged up and deteriated. Also, some of the filters were pretty poor. Luckily, the kit that I'd purchased had all I needed. The other area of note was that the metal output from the compressor that the drier unit slides onto had corroded badly and had partly disintegrated.

I replaced the filters, O rings, piston seals, desiccant and lid and reassembled. I put a 12v supply on the compressor to test the output. It was pushing out air, but did not feel very powerful, if I covered the output with my thumb I could stop the air.

Anyway, I refitted and thought I'd give it a go. Straight away there was no 'Suspension Fault' and orange light, great. Raised and lowered the suspension a few times without any problems. I then took the car over a bit of rough ground on a local Byway to see how it coped. At first, all was good, but eventually the error occurred again a couple of times. Restarted the ignition and fault went away. My conclusion is that the compressor is coping, just about, but when worked hard might struggle, maybe due to the corroded output to the drier unit. I think I'll whip it off and have another look when the weather improves again.

I have had another suspension fault on several occasions since but I don't think it's directly related, as soon as I turn the ignition, the 4wd display on the dash shows the front nearside wheel to be dropped to it's lowest position and errors straight away. The actual wheel position is fine, and as soon as I start driving the error resets itself and the screen adjusts accordingly, maybe a sensor issue?

Thanks to all who have posted instructions and advice on this forum previously, and to PowerfulUK for a good video showing removal. There are also video's on youtube showing how to strip/rebuild the compressor.