There is a regulation to use ISO VG22 or VG32 oil, but is bell hammer equivalent to the regulation?

First of all, oil is over-specified if switching from ISO VG22 or VG32.
As a cost-effective solution, adding approximately 10% of LS Bellhammer stock solution to VG22 or VG32 will prolong the life of extremely high parts and reduce friction.
This will lead to smooth maintenance without a large increase in cost.