LR3 LR4 RRS DIII Differentials
 

If you want to significantly increase the lifespan of the diffs, read on. I can speak with some authority as to the exact reason for the failures, and then the remedy.

I had my LR3/DIII serviced at the Dealer from day one, exactly by the book to manufacturer specs. I had my Differential fluid changed at 75k, at that time, they advised me I needed a new differential rebuilt and quoted some price of 4-5k with labor.

I didn't have it replaced at that time, instead I started investigating if I could get the parts, etc. and what or who else might be able to do it. During this investigation I discovered that the parts were not available at the dealer, or anywhere else. I revisited the dealer on the subject, and discovered they were swapping the unit, not repairing it. No mention, just the usual dumb look, when I asked if there was a core swap, surcharge, etc. I then specifically asked if they could get the bearings and parts, and they claimed it couldn't be done. I asked them to give me the numbers on the bearings they claimed they had, and couldn't cross reference, no reply.

After lengthy investigation I found the bearings, and Ring & Pinion. After getting the parts in, and the additional bits needed, I located an Indy shop with good experience rebuilding differentials. So finally, I got it on the rack, and they pulled off the differential, and drained the fluid, etc. At 90k, just 15k after the fluid change, the fluid was milky and contaminated with water. Now, considering we live and a dry climate, and I have not forded any water (one time since I owned the vehicle) I don't understand how/why the diff oil is contaminated in such a short time. The conclusions that I can come to are that, either there is a design defect causing moisture to accumulate rapidly and not escape, or that the dealer did not actually change the fluids, as they claimed and charged me for. Now, you could argue that the damage was done from 0-75k miles, but that does not explain the water from 75-90k.

Now the lessons that can be taken from this based on talking with the Indy shop, is that water, and the resulting rust did the damage. So, I would have to say, it might be well advised to change your Differential Fluid every other oil change, or say every 14-20k miles. I don't currently have a warranty, but even if you do have a warranty, who wants to deal with getting repairs done, not having your vehicle, and all the other associated hassles. LR should change this fluid under warranty at least every other oil change, but if they will not, I would suggest you do it yourself, or pay the extra money to have it done.

Finally, the proof, I have several detailed photos, the only ones I know of, of the diff torn apart, and showing the rust and damage. The photo attached is the locking mechanism side of the assemble internals. The Indy shop, said in general it is a very slick designed differential, and well made, aside from the water. So, the only preventative before damage, is to change your Diff Oil's at least every other oil change in my opinion. After the damage, the only solution is to rebuild it, and then change every other oil change again. It could be said, that by doing every other, and monitoring the quality of fluids when drained, it might be possible to increase the frequency. And any time you operate in water, and extreme wet conditions, it might be well advised to drain and refill them.

I highly suggest, you consider changing your differential fluid ever other oil change, or third, and always after fording through water. After a lot of research, and contacting Royal Purple, I decided to try it. Most people have reported good success, and quieter operations in general with it. Here are the specs needed for the transfer box, and front and rear differentials.

Transfer Case: Royal Purple Synchromax (part #01512, quart bottle) or Royal Purple Max ATF (part #01320, quart bottle); 1.6 quarts

Differentials: Royal Purple Max Gear 75W-90 (part #01300, quart bottle); 0.65 quart for the front and 1.6 quarts for the rear (locker)

I also replaced about 1pt power steering fluid with Royal Purples.

If you want to locate parts, or see high quality images PM me with your name, address, phone, e-mail address and I will get you information. Check out my gallery for pictures of new and old ones..

DISCO3.CO.UK Photo Gallery - Home > Member Galleries > tlt

having read your post on several forums, I'm changing the oil in my front diff and ear locking diff this weekend on my 2008 LR3 w/31K miles, though sticking with the LR oils...just picked up 1 quart of the LRN75921 (open diff oil) and 2 quarts of the LR019727 (electric locking diff oil) last night

Hi;

Sorry for the enthusiasm, on the posts, but getting the word out will save people great pains. Great Plan on the change, don't forget, when you fill the diffs oil, to put in the precise quantity, you don't fill to the fill holes like some diffs. Also, there is torque specifications for the plugs.

Courtesy of bbyer on Land Rover Repair Forums - LRRForums.com

Nobody ever regretted over lubricating something..

<snip>
If you are lucky, on the newer differentials, both the fill and drain plugs should be for a 3/8" square drive end. Below is what is posted on the thread. Note serial numbers are of the differential, not the vehicle.

Note For Front Diff:
Up to differential serial number 254845: Tighten the hexagonal drive drain plug, (14mm), to 54 Nm (40 lb.ft). Filler is 8mm hex.
From differential serial number 254846: Tighten the 3/8'' square drive drain plug to 28 Nm (21 lb.ft). Filler is supposed to be 3/8" square drive also.
The Filler plug should be tightened to 34Nm

Note for Rear Diff
Up to differential serial number 254325: Tighten the hexagonal drive drain plug to 54 Nm (40 lb.ft).
From differential serial number 254326: Tighten the 3/8'' square drive drain plug to 28 Nm (21 lb.ft).

The Filler plug should be tightened to 34Nm

I also completed the Transfer Box oil drain. (uses Special Transfer Box Oil instead of XO Diff Oil). The Transfer box used 8mm hex head for both Drain and fill.
<snip>

Interesting. Thank you.

Where is the filler plug on the front diff?

May as well replace the front breather cap as well.
 

While you are doing the differential oil change thing, you may as well replace the front differential breather cap with the new design cap that is on all newer production and per another one of those "secret" Land Rover recommended TSB's. The link below has the details. It is one of the few modes you can do standing up and for about thirty dollars.

The breather is made of some sort of Gore Tex material and is supposed to breath but not let water in or oil out. For some reason, there is no TSB on the rear diff breather.

DISCO3.CO.UK Photo Gallery - Breather Cap Front Differential installation

I think the reason for doing the breather replacement now is so you do not have to learn how to replace a pinion seal per the link below.

LR3 Front Differential Pinion Seal Replacement Instructions Attached - Land Rover Forums : Land Rover and Range Rover Forum

Also per the link below, credit for the design of our front and rear differentials goes to DANA Spicer Corporation of Ohio USA. Dana proudly calls them the Clam Shell design part way down on the brochure.

http://commercial.dana.com/images/cs...AxleSS_web.pdf


Below is a link re supply of the frames as well as the front and rear differentials out of Dana's UK plant.

Dana - News Releases


Re the oil fill plug which you will undo before you undo the drain plug, with luck you will find the fill plug on the same side as the sort of axle mounting bracket arm thing - just above it and kind of hidden by it at the end where the bracket bolts, (3), to the front diff housing.

Another way of saying it is the drain plug is just to the rear of the left side wheel drive shaft. I guess we are referring to the steering wheel side in USA and Europe. It would be difficult to find a more difficult location I tend to think.

Check out my thread on oil changes; front diff included with pictures as well as the breather replacement.

https://landroverforums.com/forum/sh...774#post350774

Impressed with the link and the pictures.
 

I am really impressed with your pictures, particularily the two showing the front differential oil fill plug. A little bit of mud and one would never find it.

Your breather replacement jpg's are sure better than mine as well.

You must be using some sort of spot light and a good camera as well.

Thanks! Just a shop light and my iPhone, believe it or not. And I need to rotate the pics to the correct orientation.

And thank you for your write ups, as they were the basis for mine

Not studio lights and some Panavision movie set thing?
 

IPhone and shop lights, now that is a surprise.

I really did figure some sort of spot lighting with a Pentax or Nikon and a good lens. I am even more impressed.