Liqui Moly Proline Diesel Systemreiniger 5156

Dear Tengkvist,
thank you for your inquiry and your trust in our products.

You can use the whole can of the Pro-Line Diesel-System-Reiniger (#5156) for your fuel tank (volume of 55 liters).
You get the best cleaning effect by using this additive with an volume of 45-70 liters of fuel.
If you use the whole 500 ml with less than 45 liters it does not cause any damages but you definitely do not have a better cleaning effect. After mixing the whole can of the Pro-Line Diesel-System-Reiniger with more than 70 liters of fuel the cleaner will not be that powerful anymore.

According to your second question:
It is not necessary to reduce the volume of Pro-Line Diesel-System-Reiniger to 350 ml.
The cleaning effect would not be the same as it is when using the 500 ml of the Pro-Line Diesel-System-Reiniger.

Best regards,
your LIQUI MOLY team