Classification of main bearings

Fig 1: Identifying Classification Marking On Block And Crankshaft

Courtesy of VOLVO CARS OF NORTH AMERICA.

The marking is stamped on the cylinder block and crankshaft.

Cylinder block classification / Crankshaft classification	A small diameter		B medium diameter		C large diameter
	block	intermediate section	block	intermediate section	block	intermediate section
A small	yellow medium	yellow medium	yellow medium	blue thick	blue thick	blue thick
B medium	red thin	yellow medium	yellow medium	yellow medium	yellow medium	blue thick
C large	red thin	red thin	red thin	yellow medium	yellow medium	yellow medium