Shell Spirax S5 CVT X

Worth knowing

The Shell data sheet gives the whole first-page list under one heading, “Meets requirements/ suitable for use”, and the Mercedes-Benz line is worded even more cautiously: the fluid is suitable where MB 236.20 approval is required. That is a claim of suitability, not an approval, and the MB 236.20 page records the code the same way: all six fluids there hold it only as their maker’s statement. In the same list Chrysler CVTF+4 is written as “Jeep CVTF +4”. How to check an oil approval explains where to find the carmaker’s own record rather than relying on the wording on the can.

Of the neighbouring Spirax S5 fluids in the catalogue, DCT X, DCT 10, DCT 11 and ATF X, none has these codes, and the data sheet of Spirax S5 ATF X (ND) expressly rules out using that fluid in CVTs. The near-identical viscosity at 100 °C of Spirax S5 DCT 10, 6.3 mm²/s against 6.2, does not make it a replacement: no codes are shared, and its data sheet names only Geely 7DCT gearboxes. The CVT X data sheet itself ends its applications table by advising you to follow the carmaker’s requirements and the owner’s manual.