Disco 2 Differentials and Transfer Box

2003 Discovery 2 Td5:

Not too long before I'll need to drain and refill my differentials (working to 50,000km between fluid change); LT230 transfer box done in more recent times (had to get a mechanic to undo the fill plug - took him a bit of effort; hopefully I can easily remove myself this time around!), but I might do all three at the same time.

Now, have started towing a bit, so just wondering if anyone has any suggestions, especially with summer approaching.

Do I fill diffs and transfer box according to RAVE fill volumes, or fill to level? Reason I ask, is that an Atlantic British video I watched stated that you must fill according to stated factory volume and not level?

Any recommendation on best fluid to use?

Having done extensive heavy towing with mine I would say just fill to level as prescribed in manual/RAVE etc. Only justification I can imagine for "overfilling" might be if you were going to be working on steep inclines or side slopes, which would not be clever with a caravan or large box trailer anyway.
Also, the only way I could think of overfilling would be to tip the vehicle so that the filler hole was higher than usual, without relooking at the manual, assuming the filler hole is the same as the level checking hole.

When you drain the fluid you never get it all out, so if Atlantic British are suggesting that you should only add a specific volume, then what residual fill level are they basing that advice on? I always fill to level as described in RAVE; you know it is not under filled and as long as the vehicle is level I cannot see how you could overfill.

Si Click said:

When you drain the fluid you never get it all out, so if Atlantic British are suggesting that you should only add a specific volume, then what residual fill level are they basing that advice on? I always fill to level as described in RAVE; you know it is not under filled and as long as the vehicle is level I cannot see how you could overfill.

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totally plus 1 on this!

plus 2

Once the new oil starts coming out of the level plug hole, the gearboxes and diffs are at their Fill From Dry capacity as stated by RAVE. You can verify this from the attached TSB.

If i was in Australia i'd buy this myself https://www.supercheapauto.com.au/p...=size&prefv2=2.5+Litre|4+Litre&sz=60&start=15

sierrafery said:

If i was in Australia i'd buy this myself https://www.supercheapauto.com.au/p/penrite-penrite-outback-4x4-trans-gear-oil-75w-90-4-litre/569584.html?cgid=SCA01070502#prefn1=adArticleType&prefv1=Differential+&prefn2=size&prefv2=2.5+Litre|4+Litre&sz=60&start=15

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Looks fine, but I would love to know what "Outback Hardened additives" are.

Si Click said:

Looks fine, but I would love to know what "Outback Hardened additives" are.

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Red-back spider venom?

Intestinalworm said:

Okay, RAVE has 1.7L for each diff and 2.1L for the transfer box - that's 5.5L total (refill volumes).

Will change and fill to bottom of fill plug (just starting to pour over).

Looking at suitable fluid - not cheap from what I've seen! I will need 6L of 75W/90 (GL-5). I found
Castrol Syntrax 75W90 Universal Plus Manual Transmission Fluid @ $26.10 per Litre (automotivesuperstore.com.au). For 6L that equates to $156.60 (86.74 GBP)! The Castrol is a full-synthetic oil, but I can only find in the 1L containers.

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When I have been forced to buy stuff in multiple 1L bottles my place gives me the same price as a gallon container, they do give me trade discount anyway, but they ackowledge that it is their fault and not mine that they don't have the larger quantities. You could try using that argument. Depends on how well you get on with your supplliers. Personally I wouldn't go for the latest CarlosFandango fluids, which cost loads more, unless there was a well-founded reason. LR do test all their vehicles so they can cope with harsh conditions and then recommend the correct fluids.
Just saying.

Okay, results of further research! Checked Supercheap Auto (sierrafery's recommendation) - "Penrite Outback 4x4 Trans Gear Oil 75W-90": 4L - $60.99 and 2 x 1L - $19.99 = TOTAL $100.97.(55.93 GBP). I found out this product is exclusive to Supercheap Auto - not available elsewhere.

Happened to just come across a Repco Sale whilst searching - "Repco Gear Oil Semi-Synthetic 75W-90"; they have a 5L - $51.75 and 1L - $12.75 = TOTAL $64.50 (35.71 GBP).

Both of these options are much cheaper than the 6 x 1L bottles of the Castrol product I previously mentioned.

Both of these options have free delivery. I believe the Repco branded product might be supplied by Penrite (Trans Gear 75W-90 Semi-Synthetic).

Might go with Repco then.