Switching to synthetic oil

[bmwman91]

Yeah, synthetic will leak a bit more. You can make the switch any time if you do decide to do it.

[bsturman92]

I have been running Valvoline 10w40 conventional the entire time I have owned the car.. I have read that switching to synthetic will increase the chance of leaks.. especially if I already have some...... can I just switch over to synthetic whenever I want.. drain what I have and fill with synthetic?

[bmwman91]

15 40 or 5 40 synthetic is what i run 15/50 is way thick imo

It is thick, but it also recommended in the manual for a reason. Directly actuated bucket lifters require higher quality oil. Thanks to an EPA change in 2008, Mobil 1 15W-50 synthetic is one of very few oils left with reasonable amounts of ZDDP. The thicker oil is not robbing any measurable amount of power or fuel economy.

[bmwm42]

15 40 or 5 40 synthetic is what i run 15/50 is way thick imo

[bmwman91]

Mobil 1 15W-50, change oil every 10k miles, Mahle filters every 5k miles. Done. This assumes that the car sees street duty and maybe an autoX here and there. If you track it, then change the oil more often.

M1 15W-50 provides the best protection for your money when it comes to street oils since it has high zinc and phosphorus levels, which many oils lack these days. Castrol 10W-60 TWS oil is better, but ungodly expensive and completely unnecessary for a stock m42.

[bsturman92]

Hey guys... Been running 10w-40 conventional oil for few years now.. Been wanting to switch to synthetic but read good and bad reviews... I have a few leaks already so what would u guys suggest?