Thread: Thoughts on breathers?

Poking around under my recently aquired D3 today and had a look at the rear diff breather setup (runs up near the fuel filler by the look of it).
I didn't locate the Gearbox/TR breathers as I decided it was more important to attend to a few other minor issues.

So I decided to seek your thoughts as to if a D3 needs any additional attention to Diff, Gearbox & Transfer case breathers?

My D3 is not intended as a long distance tourer and generally I avoid deep water and mud anyway.

Thoughts, comments?

After reading through the thread, I get the impression nobody is worried about water contamination, and are assured based on these breather tubes. Think Again!!! The K is stated in Miles, rather than Kilometers.

If you want to significantly increase the lifespan of your 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 my differential rebuilt (front and rear) and quoted astronomical price. Now I certainly can attest to the proficiency and professionalism of the dealer, as most folks I have tried to get service from besides them don't even return your calls locally. It still is a lot of money, for something I didn't feel should ever, if at least very rarely go bad, man was I wrong. This is a common failure for these models, and the only thing on the market is new ones, or used ones.

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. I was 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. I have to believe the change was actually done, due to their reputation. So now you could argue that the damage was done from 0-75k miles, but that does not explain the water from 75-90k.

The front differential was not nearly as damaged or worn as the rear differential, and did not have nearly the water that the rear differential had, this leads you to believe that there is a design related issue in regard to the water ingress on the rear differential. Also, the transfer case oil was drained, and replaced. There was fairly little contamination there was well.

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. Lack of lubrication did the rest. So, I would have to say, it might be well advised to change your Differential Fluid every other oil change and monitor for moisture possibly increasing the interval, or say every 14-20k miles or anytime you have forded through deep water. 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, and then increase based on oil condition, etc. 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.

After the work was done, wow, what a difference. It now is smooth, quiet and very little noise, I would venture to say, better than new.

If you want to locate the repair parts for front or rear differential for your LR3 LR4 RRS etc PM me with your name, address, phone, e-mail address and I will get you information, etc. You cannot get these parts from the dealer (dealer inquiries welcome) Check out my gallery for pictures of new and old ones..

Most any competent indy shop can perform this rebuild. Parts and labor for the job are about 1/2 to 1/4 of the dealer price.

(steps down off from soapbox)

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