Thread: OILS AIN'T OILS - R380

Writing the name here you can find the oil spec

This is the Syntrans Multivehicle 75W-90 one

I forgot to add, if you're happy with MTF 94 and can get it easily enough keep using it.
Just don't exceed 20,000km with it.


I'll look at that PDF later, I'm on the mobile phone ATM.

[edit] I just downloaded/read that spec sheet and the 75W-90 is the same fluid as our 75W-85.
The kinematic viscosities are almost identical, well within the range of blending/ batch variations I'm sure.

I've never tried anything else and I'm positive to try something new. Even I always struggle to find MTF94 and I would do without it.

What spec have to meet an oil for the R380 gearbox? Full synt ok, only GL-4? And what spec for the transfer box and differetial?

Have a look also to THIS, cold be interesting?

Originally Posted by bismillah

I've never tried anything else and I'm positive to try something new. Even I always struggle to find MTF94 and I would do without it.

What spec have to meet an oil for the R380 gearbox? Full synt ok, only GL-4? And what spec for the transfer box and differetial?

Have a look also to THIS, cold be interesting?

While many claim that a GL5 fluid should never be used in a synchro gearbox there are quite a few dual rated GL4/5 fluids that are fine and acceptable, Motul Gear 300 being one, Castrol Syntrax 75W-90 (Syntrax Long Life in Europe) being another.

The sulphur EP compounds are buffered so aren't corrosive to yellow metals, and you'll find most all modern diff oils meeting the GL5/Mil 2105E spec are buffered.

Interesting re the Mobil SHC 75W-90.
In the past Mobil has recommended against using that fluid in a synchro gearbox claiming it was formulated as a diff fluid first, also meeting the MT-1 spec for non synchro gearboxes too.
They must have reformulated it for decent synchro performance and no yellow metal corrosion.

IMO it's too viscous for the R380 at low/medium temps.
We can get away with Gear 300 as it's viscosity index is much higher, meaning it flows much better at 0*C to 40*C than the SHC75W-90.
Above that their curves would get much closer, meeting at 100*C.

It'd be fine in the t/case and diffs.

Thank you Rick! Next service i will try in my R380 Motul Gear 300 75W-90 or Syntrans Multivehicle 75W-90 keeping them for not more than 20.000 km

I'll let you know

What about this in our R380..

Royal Purple Synchromax

HERE some spec I found

Originally Posted by bismillah

What about this in our R380..

Royal Purple Synchromax

HERE some spec I found

Very, very thin, ATF viscosity.

Great shifting when cold.

Also usually quite expensive.

Originally Posted by outback jeff

Hi Inc, would you also recommend using the castrol syntrans 75-85 in the LT77 Defender Gearbox, or is there something better for the LT77?

Cheers Jeff

I have been using Amsoil MTF Synchromesh in my disco LT77S for a couple months now & all I have to say is get some.

I went this route for better shifting & wear protection due to the climate up here & I also run a fair bit more torque through it with an upgraded turbo setup.

So far the shifting is a lot smoother/easier & VERY consistent under all conditions.

Viscosity is similar to ATF (5w30) so it wont **** your oil pump.

Also planning on running Amsoil Severe Gear 75/110 in both diffs & transfer very soon.

It costs a bit more to buy but the service life on them more than makes up for the price tag alone.

Contact Lubrication Management on (03) 9794 0700 & they will sort you out. Bloke over there is a former Tdi owner who ran these lubes also.