Decided to give my Haldex and rear diff a service, as it's been about 16 months and 5k miles since I rebuilt the replacement diff (which reminds me that I must do the rebuild guide
), and as the Haldex is causing a grabbing when tuning on lock, I thought I'd take a look.
The Haldex is a pain to service in the vehicle, but also a pain to remove, so I decided I'd struggle with getting the pump and filter out with it in situ.
The Haldex fluid came out darker than it when in, which isn't a surprise. The pump pre-filter gause wasn't really very dirty, but was cleaned with brake cleaner anyway. I also hooked the pump to my bench power supply, as I'd not tested it while I had the Haldex out last year. Thankfully the pump worked at 12 Volts, drawing just under 1 Amp while running, so I figured that was OK.
I didn't bother replacing the filter, as the pre-filter was so clean.
I refilled it with fluid to the filler plug, and then set the level by drawing 70ml back out.
The diff was a bit of a concern though. When I removed the magnetic drain plug, I was shocked to see the magnet had picked up metallic fuzz.
Not much, but I'd have expected to see almost nothing.
Also the oil came out with that horrible metallic sheene, which is indicative of wear.
I rebuilt the rear diff exactly to the official LR rebuild instructions, so I was a bit alarmed to see it wearing after just 5k miles. I used top quality oil, which I know to be very good at protecting moving gears and bearings.
I've refilled it with the same high quality oil, in the hope that the metal is just the new bearings bedding in, although that seems unlikely.
I think I'll be changing the oil annually, even if just to keep the particulates down to minimum levels.