I don't have any regrets about moving up the fluid change interval. I knew the story about the coating breakdown...but I've had such horrible luck I just want to change the fluid more often. It's not that expensive and it gives me peace of mind.

Compton: Definitely just change out the breather cap, yourself if you want (it's easy) and if your fluid was changed 6400 miles ago you're probably good to go for a while.

 

Well, feel free to elaborate on your extensive experience, because I know for a fact that "every bearing failure has been caused due to rust" is complete BS. Misinformation is bad for forum rep.

I've personally seen many of these cooked bearings (from the paint TSB). It's not a matter of opinion, experience or expertise - it's a FACT that tens of thousands of 05-06 diffs have failed due to inner case coating contamination of bearings. It's well documented within all LR service and extended service circles and is pretty much a guarantee (hence the early and widespread TSB which cost LR millions). Also, the LOCKER unit you posted in the picture isn't even part of the freakin' TSB or failures - different manufacturer with a different protective coating that never failed. Also, to me.. the pic in the link looks like typical humidity rust from a part sitting dry for a few weeks, but oh well.

Urban legend? LR continues to use the coating?

The diffs aren't even MADE by Land Rover, and I 'heard' that the company which got the contract to produce the differentials went bankrupt around 08, presumably due to the failures as there must have been some kind of legal contractual obligation to cover premature failures due to negligence. I think the DESIGN of the diff was independent of the production, but in either case the incorrect coating was identified very early on by the diff manufacturer and it NEVER happened again. Of course by then you've already got next years models on the boat to the dealerships.

It's about as far from urban legend as it gets - why are all the failures (within reason, not talking random or abuse stories here) on 05-06 models? Why are ALL of those models perfect after the fix? If it was just water contamination it would impact ALL discovery 3, LR3, and RRS models up to 2010! I'm 4 for 4 on failed/replaced diffs on my 06 RRS and LR3 - you'd have to be incredibly dense to ignore the paint/contamination failure TSB and accept those failure rates.

I'm good friends with a long time service writer at a local LR dealership and he's got a ton of stories about the diff fiasco back in the days and calling in for warranty hours and parts. They were failing LONG before the first service intervals. Funny thing is that all the 07+ diffs were perfectly fine on the same LR service intervals.

Most have been swapped out by now as these model years are typically up in the 100-120k mile range. My LR3's rear diff was already replaced by LRNA (at 53k miles!) before I bought the vehicle. When I went to RP at 100k miles the fluid from that replaced diff STILL looked perfect. The front was black, burned, w/ metallic flakes, and hinted at imminent front diff failure.

Any other diff failure for other model years or on good units would be the same as any other random diff failure of any other make / model due to abuse, lack of maintenance, or maybe an occasional manufacturing defect, it's still "possible" as is any failure of any part. Probably worse due to our fairly unusual 6000lb curb weight AWD independent suspension SUVs which are... I'm pretty sure, almost unheard of (Touaregs got kinda close back in the day).

This pic was off of an 06 sport (front diff) - looks super rusty to me.

 

Yes, you are correct; each diff is a bit less than a quart which is I gather good if you are into green, but not so good as an owner.

To make it worse, the instructions/official quantity etc re filling effectively mean that the oil level does not even get up to bottom of the fill plug hole. I would say that all shops ignore that interpretation - egads!

Also remember to loosen the fill hole before you drain the oil. Also I think that early units used a variety of fill plug wrench sizes; metric, british, square, hex etc so make certain you have the wrench thing under control.

The jpg is a cut into the rear diff - the oil reservoir space is small, the casting is thick relative to the pressed tin units we see on other vehicles.

Note the location of the oil fill threaded bit.

 

Presumably then, the rear diff failure I experienced last year (on a diff replaced in 2010) was for a different reason. FWIW, the failure mode was different. There was a "clanking" sound in certain conditions and the clutch packs were failed.

So, with all this data and debate, my conclusion is that while the bad coating problem is resolved, changing fluid more often is still good practice. To resolve my issue with the clutch pack, like I said, I changed the diff locking motor as well.

 

Flame Complete- off you go, we have a winner..

 

If when changing the front breather how can you make sure the pipe is nor blocked? Someone on here said blow it out, how would you actually do that? In regard to the rear diff where is the breather cap for that? Is it plumbed into the front breather cap or does it have its own? If so where and can you make the same changeable?

 

I hate the IPad as it makes you sound increadably stupid! That should be not blocked and make the same change.

 

First, the rear; the breather is old style, just a rubber hose running from the top of the rear differential to up near the gas tank fuel filler cap with a bit of a horseshoe bend in the top of the hose to create an air lock if you really go in deep.

The rear breather pipe does not normally plug, but to test it, just slide the rubber hose off at the rear differential end and blow on it. One presumes the metal sleeve hole into the diff is open.

Re the front, look for part 34 on the 2 page front diff pdf. Item 34 is where the hose connects to on the top of the front differential. The odds are with the stock breather cap, if you slide the hose off and blow, the hose will appear plugged as the cap most likely is.

I recall that when I cut my OEM factory breather off, and blew into it, the cap acted plugged whereas the new one, prior to install, when I blew into it, did not seem plugged as the removed one did. I did not actually check the hose itself.

In summary, no the two breathers are not plumbed together; the front and rear breathers are separate.

 

FWIW the manufacturer as stated by a few fellows on the D3.uk forum that took theirs down was Dana Spicer.

I had pinion bearing failure on my front diff, not sure if that was the paint. Breather had been blocked up for years, when I emptied the differential it was over pressurized, fluid brown and opaque, I did not see anything resembling paint or coating, just bad murky oil (relatively consistent). Despite bad centre bearing, drove it for another 30k with two fluid changes, temps were a little warm, 180F+ but aside from a slight whine no issues.

 

Attached is a bit of info from DANA on what they call their Calm Shell differentials or more correctly, Spicer AdvanTEK Axles in both Salisbury and Banjo as well as our Clam Shell construction.

The Calm Shell style is for vehicles with independent suspension per our 3.