Bimmerfest - BMW Forums - View Single Post - OIL Types Used
Thread: OIL Types Used
View Single Post
Old 11-27-2012, 11:32 PM
robertobaggio20 robertobaggio20 is offline
Location: earth
Join Date: Oct 2009
Posts: 3,403
Mein Auto: car
Originally Posted by BMWE34M20 View Post
Oh...does/has anyone used high mileage oil? Is it ok to switch from high mileage to fully synthetic or do i have to keep on using high mileage?? Heard Hm oil expands thing?? O.o
A. Only use fully synthetic engine oil (check the label to confirm). Prices are damn low, engine protection is greater, and drain intervals are doubled. What's the downside ? Mobil 1 retails at walmart for under $30 ! Its ridiculous.

B. High mileage oil is simply thicker oil. Thicker oil helps for older engines as older engines have worn piston rings which don't seal the combustion chamber as well as when new so your compression suffers. Thicker oil helps to compensate somewhat for this wear, and you get more power as a result, even factoring in the greater friction created by thicker oil.

C. There is thicker fully synthetic oil available in the market ! So, only use products labelled as high mileage oil if it also states that it is fully synthetic.

D. HM oil does not expand things, does not swell gaskets to compensate for ruptures, etc...all that stuff has been more or less proven to be false. HM oil reduces the amount of oil that escapes an existing leak, that's true, but its just because its thicker and thus flows out less easily both when hot and cold.


Last edited by robertobaggio20; 11-27-2012 at 11:34 PM.
Reply With Quote