As this has been asked on several occasions I thought it would be wise to explain the background to the VW 505.01 oil and why it's so important to use it in a PD engine.
It is vitally important to use a PD oil in the PD engine due to the pump.
The VW pd engines are very severe on the oil, the mechanical fuel pump delivers fuel at approx. 25,000 psi !!!!! to enable a very precise injector spray pattern which, in turn, gives excellent driving characteristics.
The very high loads on the fuel pump will lead to VI improver shear down and oil viscosity loss if the engine is operated on lesser oils.
The surest way to shorten the life of your engine is to ignore this advice.
Cheers
Guy
It is vitally important to use a PD oil in the PD engine due to the pump.
The VW pd engines are very severe on the oil, the mechanical fuel pump delivers fuel at approx. 25,000 psi !!!!! to enable a very precise injector spray pattern which, in turn, gives excellent driving characteristics.
The very high loads on the fuel pump will lead to VI improver shear down and oil viscosity loss if the engine is operated on lesser oils.
The surest way to shorten the life of your engine is to ignore this advice.
Cheers
Guy