Oil change issues

I have just purchased my new 1990 90. I am told its had a gearbox and rear axle change to that from a disco, but thats all the info i got.

In the middle of changing fluids, but having a couple issues.

Gearbox- the plate with the code is not legible...AT ALL! Oil came out the colour it would go in!

Transfer box - R380, couldn't find any oil from the filler plug and hardly any came out the drain, but what did come out was manky. The drain plug had swarf(?) on it, but not a huge amount. Is there any way to check for damage due to lack of oil? The gearbox is smooth enough when driving, but how do i check the transfer box?

Both diffs had limited amounts of oil in them. What came out was the typical milky colour, but also some thicker black oil too. I notice that on the hub axles, a couple bolts look oily.... would the oil be coming out there?

On the rear diff (axle has disc breaks, but diff looks same shape etc as the front), there is oil around the assembly.... Where could this be coming from? Is it likely that there could be a crack or something on the diff?

The transfer box is fairly straightforward - you can take the plate off the bottom and have a look at the condition of the cogs inside. The main gearbox (i.e. the R380 bit, if you have that model) is more difficult without some serious dismantling. I think most people would change the oil and leave it alone if it wasn't unduly noisy and was changing satisfactorily. It likes MTF94 (or equivalent) rather than gear oil as it needs something thinner for the synchromesh mechanism to work satisfactorily. It's possible for the diffs to crack, but very rare. Sometimes the pan rusts through or gets pierced by hitting an obstacle, or what's more likely is there's a small leak at the pinion seal or the join where the diff carrier bolts on to the axle casing. If it's just damp with oil, most people wouldn't see this as a problem, but if it leaves stains on the ground regularly or needs topping up frequently, it could do with some attention. Same goes for the front axle, swivels etc. Make a judgement about how much it seems to be losing and whether it merits the effort of rebuilding it. There's often a bit of material on the magnets in the drain plugs. If they come out looking like a Christmas tree or have larger items stuck to them it might be more worrying.

Sounds like it was well overdue for an oil change in the transmission components. Give them all a drink of something nice and they should be OK for another few thousand miles.

Thanks - exactly the response i was looking for....glad to hear nothing too scary yet. I'll consider taking the cover off the transfer box tomorrow before i put oil in.

I have ATF II (ATF & Power Steering Fluid) for the gearbox. I believe thats the right stuff? Diffs have 75w90 (couldn't get 80w90 at the time of buying), so should that still be acceptable? I figured something was better than nothing! Need to get some more for the transfer box, so will try and get 80w90 for it.

As a further question... I have just read a few things on forums saying that I should really put ATF into my transfer box, rather than 80w90. Thoughts?

I wouldn't worry too much about oil on the hub bolts. If it gets an oil stain around the whole hub it's the gasket. They cost diddly and are simple to replace. Need a torque wrench. Main thing is to keep the differential properly topped up. Similarly a differential gasket cost about £1.50. Changing that involves removing the differential, more work.

Rorie said:

As a further question... I have just read a few things on forums saying that I should really put ATF into my transfer box, rather than 80w90. Thoughts?

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My thoughts are you should have a re-read, ATF can be used in the gearbox (R380) but the transfer should be proper gear oil 80/90.

Kwakerman said:

My thoughts are you should have a re-read, ATF can be used in the gearbox (R380) but the transfer should be proper gear oil 80/90.

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Re-read wont help; I understood the transfer box to take 80/90 (along with the diffs) and the gearbox takes ATF. What I am saying is that there are a few threads on forums where people suggest ATF in the transfer box is the way to go, rather than 80/90....So I am asking if anybody knows why, or if that is just a heap of rubbish that people are posting?

Well I certainly wouldn't put ATF in my transfer unless it was some sort of emergency, 80/90 is a high shear strength oil designed for exactly what diffs and transfer boxes do (they are just 'dumb' gearboxes with no synchros). I imagine that ATF would find all the weak spots and start working its way out. If it is a new vehicle to you as a start point just stick with what the manufacturer recommends first time round , you could always try ATF at the next oil change once you know what the leak rate is with normal 80/90. Your toy, your choice.

Thanks - was planning on using 80/90, but those threads I found threw me a bit!
Given the lack of oil in all components so far, I think going with the standard as a starter is the correct thing to do!

Cheers

Sometimes in conversations about transmissions, people are a bit fuzzy about which bits are which. Even the most ardent Land Rover fan in some cases. So it may be that people are getting mixed up as to which bit is which.

Called a few places for 80w/90 and all I can get is mineral, not synthetic or semi. Is this acceptable? I cant find any ref online as to what kind of 80w90 to get...

Thanks

Don't think 80/90 would ever be synthetic, bog standard mineral would 'achieve' that spec on its own! Do check your're referring to the right bits - you called the transfer box the R380, but that's the gearbox I believe...? Sounds like it will enjoy some tlc anyway, have fun! I think some numpty did not use MTF \ ATF in mine last year, and synchro to second in particular gets caught out easily, will be swapping it soon.... Cheers, A