M42 Oil Change, what do you use?

[fernn]

hey guys i have 3 318's and its funny because on 2 of them I'm due for a oil change in the same time, i have been using 15w-50 mobile 1 synthetic oil, i buy the gallon from walmart for about 25$ or so, and then i use a mahle oil filter,
any recommendations? basically i hear that the m42's need more zinc, but what do you guys use?
i mean if I'm going for cheap ill buy some auto zone cheap oil, but do you think i can get mobile one for cheaper online? id be wiling to buy like 20 qts?
and has anyone used Royal Purple?
i know ecs tuning has the option of buying 10 oil filters in bulk, so i will do that.

let me know guys, thanks!

[Vivek]

Everything I've heard about royal purple says it's overpriced junk. The m42 doesn't even need synthetic anyways, there's not much of a point in running it. I found this one 15-50 heavy machinery diesel oil that was like $15 for 2 gallons at o'reilleys once and used that for a while. Normally I just buy whatever's on sale, which is usually castrol gtx. At the end of the day, oil is oil and I'm pretty sure even o'reilleys store brand is made by pennzoil.

[fernn]

Much apreciated Vivek!
Yea I'm starting to realize that too, at the end of the day is it really going to let me beat a Ferrari haha. But I'm a stickler for having everything done right the first time so I'm just to scared to use cheap oil because I'm afraid it will be a bad outcome. I always say in my head, what's an extra 10$? Haha, I'm acutually running the Diesel in my car now because a buddy of mine recommended it, it might just be me but I feel like the motor is a bit louder in the cylinder when cold? Then before when I had 15-50 M1?

[KW E30]

i use shell rotella t 15w-40 great oil so far!

[roguetoaster]

Buy whatever is on sale. When you find one that your car seems happier with try to buy it again. Clearly, with a cheaper oil you might want to change your oil more frequently.

As for me I use Castrol, Mobil, Shell, Valvoline synthetics most frequently, and tend to skip Pennzoil for some reason. But if they are not on sale I might use Castrol GTX or maybe even Rotella T6, all in 20w-50 (or a blend if they are don't have enough 20w-50).

[fernn]

what do you guys change your oil at as far as miles? i have been doing every 3000-3500 miles lately, to some thats to soon i guess? and thats with mobile, I'm so far 2500 miles in with the diesel i have in now and its kind of making me wonder. i have about 175k and on the mobile1 site it says to use 0w-40? haha

[Vivek]

Use 15 or 20w-50. These engines need a thicker warm viscosity. Anything thinner will burn more and likely cause more lifter noise. 3k is quite often, I normally do around 5k miles.

[bmwman91]

I have had the best results with synthetic Mobil 1 15W-50. It has some of the highest zinc and phosphorus levels you will find in non-race oils. They publish technical data on their stuff, which I appreciate.

http://www.mobiloil.com/USA-English/MotorOil/Files/Mobil_1_Product_Guide.pdf

The 15W-50 oil in their sheet also says that it is for flat tappet applications, which is us.

On my custom built M42, I was running Castrol 10W-60 TWS oil at the recommendation of Metric Mechanic. It is great stuff...superb cold start smoothness. However, it costs $18/L and leaks like a MOTHERF*CKER. I lose a liter every 1000 miles on a newly built engine. It was never intended for use with paper gaskets.

Per Metric Mechanic, the M1 15W-50 is the 2nd best oil they have ever tested (the 10W-60 stuff is #1), and #3 is a distant fraction of the performance.

I change mine every 10000 miles, with a filter every 5000. It is a tremendous waste to change it at a smaller interval...assuming you run high quality synthetic. Dino oil...I'd probably do every 5000 miles.

[fernn]

much appreciated for the info vivek, its good knowing what others are changing there oil at so I'm not lost in the dark,

bmwman91, thanks for some great clarification, i think I'm going to stick with the M1 15w-50 for now, i think i can even get it at costco for like 35$ for a case of 6qts, I'm going to see if i push it to 4000k on the next change , after I'm done with this diesel,

if i find that M1 15w-60 ill definitely do that next, I have a tendency to wake up late for work/school and leave my house with out warming up my car so i want something thats not going to let me hear the lifter noise in the mornings.

[bmwman91]

I would avoid the Castrol 10W-60. It costs $$$, leaks like crazy and a member here has a relative working in Mercedes' oil division that says it breaks down after 5000 miles. It is literally $110 for the oil & filter when you do a change with the stuff...not worth it IMO. It was developed specifically for the new M-series cars' engines, and there is no practical need for it outside of that. They must figure that if you can afford a new M-series, you can afford to maintain it (you'd better be able to lol)!

I have never "let my car warm up". I start it, let it sit for a few seconds to make sure that oil pressure is steady and then I drive. I don't floor it or rev it past 3500RPM until it is fully warmed up, but there is no need to sit idling in the driveway. That's probably worse for the engine. You have the lowest oil pressure at idle. One related note: NEVER start the car with the clutch pedal pushed in. Stock M42's only have half of a main bearing as a thrust bearing, so when you start it with the clutch in, you have hundreds of pounds of force on that measly bearing surface with zero oil pressure. It's the kiss of death in terms of crank end-play. Even on a properly rebuilt bottom end with 360 degree thrust bearings, it's not a hot plan to start the car with such a pre-load on there.

[elbrack]

I buy only Castrol GTX High-Mileage 20w50 as recommended by mechanic who's been working exclusively on BMWs for over 20 years. If it works for him, it works for me.

I think synthetic is a waste of money if the engine didn't start on synthetic. It really doesn't need it either.

[kwill22]

I use Mobil 1 10w-40 but I found a walmart that carries he 15w-50. I tried it for the first time when I changed my oil change about a month ago. I get on and off ticking for a minute or two when I start my car now but I'm sure it's because of the initial thickness.

Technically 0w-40 is ok. so the Mobil 1 website isn't really wrong but I actually tried the
0w-40 and it was fine until it broke down not even 2k miles in. Got to thin for our hot weather so It might be better in colder climates but I wouldn't risk it. Engine just randomly started ticking horribly one day while I was out. Changed my oil as soon as it started.

I'll probably go back to 10w-40 on my next change to get rid of the tick. I use mehle filters Also. Change around 5k.

[beta14ok]

Rotella 15W40....or Liquimoly.

I'm at 200k and she likes it thick.

[cferb]

I've heard Pennzoil is not a good oil...

I use castrol 10w40 in most of my cars, it doesn't get terribly warm here so I tend to lean more on the lighter weight side. Mobil1 is good too, I just use Castrol because I always have.

Bmwman is tight in the 10k oil, 5k, filter thing, that's closer to the proper interval, 3-5k is a made up interval by oil companies and is really way too often, the filter does go bad faster than the oil though and on a lot of cars you may as well do both at the same time, m42 is easy though. Still I aim for around 5k anyway, it's not that expensive and leaves me some room to do it whenever I have time and not worry about waiting too long.

It seems odd to me that you guys are saying lighter oil causes lifter noise, isn't lifter noise caused by oil not getting to the lifters? Which would be more an issue of heavier weight...but maybe I'm wrong.

[kwill22]

if they're too thing the oil pump can't pump them as well, like pumping water, so that could also cause the tick from the oil not getting where it should and lubricating as well. (Same point you made basicly) except that oil that is too thick can also be a problem for being to thick to pump efficiently. Just depends on your engine.