jjs 64 Report post Posted October 31, 2006 Just about to do an oil and filter change. What oil is the best for an M50 325i, want something good but not fully synthetic. Also, does anyone recommend any additives to put in with the new oil? Cheers Quote Share this post Link to post Share on other sites
m325i 709 Report post Posted October 31, 2006 Motor Up FTW Quote Share this post Link to post Share on other sites
Yuen 16 Report post Posted October 31, 2006 I switched from Pennzoil dino oil to Castrol Formula R (full synthetic). It's going great. FWIW, I thought Castrol Magnatec would be ok if you aren't looking to go full synthetic, but my mechanic told me that Magnatec is some lousy stuff. He recommends Fuchs, they're german I believe, and they have a good reputation overseas. I believe they're OEM for some car manufacturers. Price ain't too bad either. Quote Share this post Link to post Share on other sites
WarNox 1 Report post Posted November 1, 2006 I think I asked team mcmillan and they said Castrol Magnatec, so i put that in. you shouldn't swap from non-synthetic to synthetic as it might kill all your seals or something, i read that somewhere. Quote Share this post Link to post Share on other sites
my_e36 43 Report post Posted November 5, 2006 I've read somewhere else that says switching from dino to synthetic does no harm and it doesn't matter when in a cars life time you change it. I seem to recall Castrol is somehow related to BMW as many BMW garages have Castrol logo all over. Quote Share this post Link to post Share on other sites
Yuen 16 Report post Posted November 5, 2006 (edited) I think I asked team mcmillan and they said Castrol Magnatec, so i put that in. you shouldn't swap from non-synthetic to synthetic as it might kill all your seals or something, i read that somewhere. The general consensus is that it is a little risky to swap from dino to synthetic if your car is over 128,000kms. Reasoning is that the molecules of the synthetic oil are smaller than dino oil, so it might get through any gaps in the seals/gaskets that the dino oil, having bigger molecules, did not get through. I thought what the heck, and did the change right around 140,000kms, no problem, and I'm glad I did it Edited November 5, 2006 by Yuen Quote Share this post Link to post Share on other sites
kiwipetrolhead 1 Report post Posted November 6, 2006 I use Mobil 1 synthetic in both my old '83 e21 323i and also my '94 e39 540i. It's very good stuff, but all synthetic is. But I agree, do not mix it with non-syn. As for syn causing leaks and stuff, that can happen. I used to use it in my old '83 Renault Fuego, but I switched back to mineral oil and the oil leaks stopped after a while as well. No problem with leaks in my BMWs using Mobil 1 tho. If using non-syn, buy the best you can get. (Synthetic is expensive.) BTW, if you move to Synthetic, it pays to carry a litre spare in your boot. Cheers Paul Re Motor Up, it is any good? (I am always sceptcial of oil additives.) And is it safe to use with synthetic oil? Paul Quote Share this post Link to post Share on other sites
kiwipetrolhead 1 Report post Posted November 7, 2006 One more good tip - I always prime my oil filters. That way, oil pressure comes up almost as quick as a normal start up. In fact, when your oil filter is mounted up side down (like it is on my 323) you can completely fill up the filter before screwing it on to the engine. If it's not mounted up side down on your engine, just put as much oil in as you can without it draining out when you hold it on the same angle as it will be when placed on the engine, but also make sure the entire filter paper is wet to maximise this. Remember, over 90% of wear takes place at start up, more so when the engine is cold...and while there is no oil pressure. Do garages do this on customer's cars? No, of course not. But I ALWAYS have! Cheers Paul Quote Share this post Link to post Share on other sites