The only oil recommended, for Volvo manufactured transmissions is that whiari has quality GL-1. The teeth in the Volvo transmissions are so dimensioned that there is nojneed for any additives of sulphur or phosphor. The judgement being therefore that there is hardly any advantage in uajng these additives. For this reasDTiGL-4 and GL-5 oils are not recommended for Volvo manufactured transmissions. The seals in the Volvo transmissions are of a very high quality and normally withstand GL-5 oils. Also the steel/ molybdenum synchromesh does not appear to be par- ticularly sensitive to this oil.

Problems can however arise at very high temperatures, such as when driving in mountainous terrain or when the power take-off is being used. There is a risk that deposits from the oil form a coating which block the oil filter and oil channels so that the operation of the oil cooler is impaired. We therefore advise against the use of GL-4 and GL-5 oils in Volvo manufactured transmissions. The German transmission manufacturers recommend GL-4 oils. We approve therefore the use of GL-4 oils in Volvo vehicles with ZF manufactured transmissions. However even here we firmly advise against the use of GL-5 oils.

AUTOMATIC TRANSMISSIONS, POWER STEERING Trucks fitted; with Volvo automatic transmissions require ATF quality Dexron II D to facilitate smooth gear changing. Very great demands are made on oil for automatic trans- mission and power steering installations. The oil must have a very low sensitivity to temperature, that is, temperature variations must have as little influence as possible on the viscosity of the oil. Moreover, the oil must have good cleansing characteristics, since deposits, for example on valves, have an immediate detrimental effect on the functioning of the unit. Foaming must not occur since the function of the unit demands a constant flow of oil. Anti-oxidation and anti-corrosive qualities must also be the very best. ATF means Automatic Transmission Fluid.

Download pdf Volvo Service Manual - Lubricants / Fluids