No more than one.

Thanks for he quick reply!:thumbup:

I would start with 1 container of lucas stop leak. However, on the V8s where this is a common problem, lucas oil recommends that up to 20% of the oil in the car be leak stop. So on an 8 quart system, up to two containers can be used.

So if 1 dosen't work try two, but give the 1 quart about 500 miles to see if it solves the problem. It does NOT work instantly.

Also I read good things about ATP-205 (gonna try) and Liqui Molly engine saver (i think that is their seal reconditioner)

Basically I think any of these will work, just go with the easiest to obtain/best value. Lucas is everywhere.

Wouldn't it be better to do with an oil change? Replace 2 of the 8 liters of oil with the Lucas product?

hey guys I am new to X community, 2 month ago I picked up X5d.
Some time ago my coworker was using Atom Engine Stop Leak from walmart and it worked really good.

Yes, exactly. I should clarify that. The lucas leak stop should be a maximum of 20% of the oil in your engine. on The V8 you wouldn't add 8 quarts then add 2 quarts of leak stop, that would be over filling. You would do 6 quarts to 2 quarts of leak stop. Overfilling a bit won't hurt the engine, but can cause it to burn more oil as according to BMW as oil from the crank is thrown against the cyclindar walls resulting in more consumption and possibly smoking (if your way over filled). N62 Oil usage - Bimmerfest - BMW Forums