Hello,
As Sol would say 'Oils ain't oils' (a local 1970s series of Mobil oil adverts).
I have been trying to find the best oils for the 435 series Unimog. In particular, the U1700. Most seem to have been made around 1988 plus or minus a decade. I could not find any existing posts on the matter.
Oils have moved on a lot since 1988 mineral oils were the norm with semi-synthetics and even 100% synthetics. Some modern mineral oils are so good, they can be called synthetics.
GEAR OIL
Vehicle instructions state ‘hypoid trans oil SAE 90 (OEP-220)' (i.e. gear oil) for axles, hubs.
However, hypoid and most spiral bevel gears usually need a GL-5, yet GL-5 produces sulphuric acid that attacks white or yellow metal. I can only assume the diffs and portal hubs don't have white or yellow metal.
Can anyone confirm GL rating of 5 for gear oil?
ENGINE/TRANSMISSION OIL
Vehicle instructions state ‘engine oil SAE 40 (OMD-115)' for crankcase and transmission.
I have read that with old vehicles, the introduction of synthetics can cause some issues with seals, by dissolving the decades of crud that have built up in the internal surfaces (which can help to keep the seals sealed).
However, assuming that this is not going to be a problem, Can anyone advise what types of oils will suit this vehicle and be best for hot long runs across Australia?
Also, I cannot find a supplier of medium size home use containers of oils here in Australia (i.e. 50 or 60 Litres). Either piddling little 20 litre drums or very large unmanageable drums requiring a drum lifter crane (not suited for use around the home garage environment).
As Sol would say 'Oils ain't oils' (a local 1970s series of Mobil oil adverts).
I have been trying to find the best oils for the 435 series Unimog. In particular, the U1700. Most seem to have been made around 1988 plus or minus a decade. I could not find any existing posts on the matter.
Oils have moved on a lot since 1988 mineral oils were the norm with semi-synthetics and even 100% synthetics. Some modern mineral oils are so good, they can be called synthetics.
GEAR OIL
Vehicle instructions state ‘hypoid trans oil SAE 90 (OEP-220)' (i.e. gear oil) for axles, hubs.
However, hypoid and most spiral bevel gears usually need a GL-5, yet GL-5 produces sulphuric acid that attacks white or yellow metal. I can only assume the diffs and portal hubs don't have white or yellow metal.
Can anyone confirm GL rating of 5 for gear oil?
ENGINE/TRANSMISSION OIL
Vehicle instructions state ‘engine oil SAE 40 (OMD-115)' for crankcase and transmission.
I have read that with old vehicles, the introduction of synthetics can cause some issues with seals, by dissolving the decades of crud that have built up in the internal surfaces (which can help to keep the seals sealed).
However, assuming that this is not going to be a problem, Can anyone advise what types of oils will suit this vehicle and be best for hot long runs across Australia?
Also, I cannot find a supplier of medium size home use containers of oils here in Australia (i.e. 50 or 60 Litres). Either piddling little 20 litre drums or very large unmanageable drums requiring a drum lifter crane (not suited for use around the home garage environment).
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