The LO basket used for filtration has what micron rating?

• A. 20 micron
• B. 80 micron
• C. 40 micron
• D. 60 micron

Answer: (C)

The key idea here is how micron rating determines what size particles a filter catches and how that affects flow. The LO basket acts as a coarse screen in the lubrication oil path, catching larger debris early to protect the pump and downstream filters. A 40 micron rating is a good compromise: it removes the larger, more damaging contaminants while still allowing adequate oil flow with a manageable pressure drop. If it were finer, like 20 microns, it would clog more quickly and reduce flow; if it were coarser, like 60 or 80 microns, smaller but still harmful particles could pass through and cause wear. So, the LO basket is designed to be about 40 microns to balance filtration and flow.