Thread: oils aint oils

Originally Posted by PAT303

The reason is because I work on tojo's etc and they have gearboxs that are nothing short of rubbish.It is not uncommon to get less than 50k before a rebuild and one of the fix's for longer life is redline oil,we have one rebuild shop and two shops that I use that do fleet services and all three use redline oils.I thought if it makes a POS box last longer it will make a good one last for ever. Pat

But do the POS boxes have an internal oil pump? I do not know - but for the R380 it is an important consideration - the oil needs to be thin enough in all conditions for the pump to be able to move it - but still thick enough to provide lubrication. Hence if there was no pump any sort of decent gear oil would probably work.

Garry

Thats the value of rover box's,they may have faults but both the box and transfer have very good lube systems. Pat

Originally Posted by garrycol

But do the POS boxes have an internal oil pump? I do not know - but for the R380 it is an important consideration - the oil needs to be thin enough in all conditions for the pump to be able to move it - but still thick enough to provide lubrication. Hence if there was no pump any sort of decent gear oil would probably work.

Garry

Garry, Pat's using MTL which has a viscosity of 10.5 cSt @ 100*C and a VI of 183 which is lineball with MTF94.
IMO MTL is a better oil, it's is a full synthetic with predominantly POE bases from a well respected boutique blender, and we can't get MTF94 anyway.

I often see the pump argument brought up and I think it has holes in it.
A number of full synthetic 75W-90 MTF's at 0*C are around the same viscosity as a normal ATF like Mobil ATF220 at -10*.

-10*C isn't that cold for a Land Rover, so I don't think that in the more temperate zones of Oz the pump is unduly stressed by heavier viscosity fluids, although an 80W-90 would be a no-no as it will be too heavy as those type of fluids usually have a fairly low viscosity index and are usually straight diff oils which are unsuitable for good synchro performance.

do all r380s have an internal oil pump 1995 defender

Originally Posted by rick130

Garry, Pat's using MTL which has a viscosity of 10.5 cSt @ 100*C and a VI of 183 which is lineball with MTF94.
IMO MTL is a better oil, it's is a full synthetic with predominantly POE bases from a well respected boutique blender, and we can't get MTF94 anyway.

I often see the pump argument brought up and I think it has holes in it.
A number of full synthetic 75W-90 MTF's at 0*C are around the same viscosity as a normal ATF like Mobil ATF220 at -10*.

-10*C isn't that cold for a Land Rover, so I don't think that in the more temperate zones of Oz the pump is unduly stressed by heavier viscosity fluids, although an 80W-90 would be a no-no as it will be too heavy as those type of fluids usually have a fairly low viscosity index and are usually straight diff oils which are unsuitable for good synchro performance.

Wasn't making comment on oils used - just stating that it has a pump for those who may not be aware of that - hence the oil has to be thin enough for the pump but thick enough for lubrication.

The LT95 in my 101 uses engine oil - if I put that (or good old plain gear oil) in a r380 I am sure it would kill the gearbox quickly.

Shad - all R380s have an internal oil pump.

Garry

Originally Posted by garrycol

<snip>
The LT95 in my 101 uses engine oil - if I put that (or good old plain gear oil) in a r380 I am sure it would kill the gearbox quickly.

<snip>

Garry

actually, an xW-40 engine oil is identical in viscosity to a 75W-90 manual trans oil.

<edit> and I should add, be careful those of you with an LT77 as the gears are a composite and not steel like the R380. The viscosity of the oil is a lot more critical.

Originally Posted by garrycol

The story goes that when the R380 was developed there was no suitable manual gearbox oil available on the market so they chose ATF as a near enough alternative.

It was found that while ATF was good for changes it was not a very good lubricant in the box and as soon as MTF 94 came on the market, Land Rover changed the specs for the R380 to MTF 94.

I know Landrover can do some silly things but they would not have changed from the ATF to MTF if they did not have concerns about it.

Garry

You might be interested to know that Mercedes-Benz has specified ATF in their manual gearboxes since the 1950s and only recently went into synthetics, however that coincided with their 'filled for life' adventure.

Cheers.

Originally Posted by rick130

actually, an xW-40 engine oil is identical in viscosity to a 75W-90 manual trans oil.

<edit> and I should add, be careful those of you with an LT77 as the gears are a composite and not steel like the R380. The viscosity of the oil is a lot more critical.

From what I've been told, Mobil one (or equivalent) is the go in LT77s

Cheers.