BMW M52 question

[KenO]

So, normally I universally run Rotella 5W-40 in these motors, and they love it. However, this last change, I used 5 quarts I had of Quaker State Ultimate Durability 5W-50, and topped off (~2.5-3 QUARTS) of Delo 15w40.

The valvetrain seems much noisier, but it seems oil consumption is down too. I guess this begs the question, whats the better sacrifice? Quiet valvetrain with the Rotella, or noisier valvetrain, but much less consumption with the thicker oil? FWIW, if I switched to a thicker oil, I'd use straight Rotella or Delvac 15w40.

 

[antonmnster]

These engines can make a bunch of valvetrain noise with certain oils. M1 made mine the loudest with my m52, but my m54 is silent with Mobil 1 0w40. Who knows.

I used Delo 15-40 with my m52 when the temps were above freezing; it seemed to like it best and it was spotless when I sold it at 253,000 miles.

 

[KenO]

Does anybody think the valvetrain noise is detrimental though? I'm assuming it's mostly lash in the lifters that can't get pumped up fast enough?

 

[BMWTurboDzl]

Originally Posted By: KenO
Does anybody think the valvetrain noise is detrimental though? I'm assuming it's mostly lash in the lifters that can't get pumped up fast enough?
wouldn't that result in a ticking noise?

 

[SteveSRT8]

Originally Posted By: KenO
Does anybody think the valvetrain noise is detrimental though? I'm assuming it's mostly lash in the lifters that can't get pumped up fast enough?


Since most valvetrain noise is the result of excessive clearance it will eventually damage something. Even a few seconds can be causing damages, just not that bad for now...

 

[cdeason]

I just did a VOA on the Quaker State Ultimate Durability 5w-50 and 5w-40, the 5w-50 had around 800ppm of zinc while the 5w-40 had 1100ppm, the 5w-40 had a overall better additive package, I use the 5w-40 in my 328i but Rotella T6 in my S14.

 

[dparm]

I would rather use oil at a reasonable and consistent rate than have a noisy valvetrain. Topping off periodically is actually a good thing since it slows down any contamination, keeps viscosity where it should be, and replenishes the additive pack.

 

[CATERHAM]

These must be very high mileage Bimmers to experience noticeable valvetrain noise. My 200,000 mile '96 is perfectly quite on a light 0W-20.
You haven't said when the noise is most apparent, on start-up or when fully hot/ If it is just on start-up running an antiquated 15w40 conventional would seemto be part of the problem.
Anyway I wouldn't use anything heavier than Mobil 1 0W-40 unless the engine was on it's last legs so to speak.