BMW 545I Auto Rx /oil/filter

[hednhtr65]

I am the new third owner of a 2005 bmw 545i with 78,000 miles. I am experiencing recently what I believe to be lifter or rod knock on cold starts that quiets after the car warms up. Planning on doing the AutoRx treatment. Sounds like I can use conventional oil for that, any suggestions welcom on specific oil or departures from the Mfg instructions for ARx treatment. The car just came off warranty and was maintained by the dealership on 15k mile intervals w/ bmw synth. oil. I live in Minnesota so cold starts are a six month window. For my other cars I have run conventional oil and done more frequent oil and filter changes myself. I will do the oil work myself on the BMW too. Any suggestion on oil, conventional or Syn. Change intervals and filters (Mann, Hengst or others
would be great.

 

[ahoier]

Filters, it's up to you. Get a decent filter and change it on-schedule with your OCIs....

As far as oil, I hear for the aRX treatment, you're fairly limited to only "conventional" oil, for the best "clean".....I'd say Pennzoil conventional should be OK, as long as it meets the BMW/ASE/ILSAC specs outlined in the manual for the vehicle.



Ever thought of Seafoam....1.5 oz. per quart of oil in the crankcase; can be ran for up to 3k miles in the oil, either POST0 or PRE-oil change? Some like to add it 500-1000 miles "before" an oil change.....but I've had just as much success with it being added right at the oil change, and ran for 3k..... Or, the Marvel Mystery Oil option? 1 qt. of MMO to 4 qts of MMO, for 3-4k miles.


If those treatments don't "quiet it down" then it's likely something mechanical...

 

[Trav]

Personally i would just run something like Rotella T and 20% MMO for 3K.
If its a rod its going to get worse no matter what you do.