oil change

[SpecM]

I've been doing some research on this lately... I work at Advance Auto, so I have access to info (like MSDS's) about oils we sell and their contents:

My top picks:

Shell Rotella 15w40 : for diesels, has a bit ZDDP, not as much as it used to but more than most other SM-rated oils
Valvoline VR-1 20w50 : it has a lot of zinc, it even says it on the bottle
Castrol GTX 20w50 : good stuff, and commonly available
Mobile One 15w50 : most zinc of any SM-rated synthetics

[nando]

no, they still have ZDDP. but the epa has been requiring less ZDDP in all oils for quite some time, due to the cat convertor.

[moatilliatta]

The thing i always wondered, Do synthetics have something in their oils to replace ZDDP. Something that works the same or better.

[nando]

what oil do you use?

mobile 1, but I've been doing a bit of research on ZDDP. Even some of the oils that claim to have high ZDDP or ones that everyone thinks contains high levels don't have that much. There's also debates on how much is adequate in the first place.

I'm not sure that the levels found in Mobile 1 are detrimental - at least, I haven't noticed any cam wear in ~45,000 miles. I think it may be more critical during cam break in than regular use, although you should be using something specific for that anyway.

[reelizmpro]

What are you talking about? the manual specs 20w-50 or 15w-40. How's your oil consumption with 10w-30? if it works for you then it's all good.

[TexasTerp]

Y'all are running some thick oil! I've been running on Pennzoil High Mileage 10w30 for the last 120k on my 280k m20. Runs nice and quiet and haven't had any issues at all. Then again the car spent 20 of it's 22 years in Houston.

[SpecM]

also do some time searching on ZDDP. Rotella doesn't have nearly as much zinc as people think. it's also formulated for diesel engines, entirely different application

what oil do you use?

[nando]

No, synthetic is pointless in a motor that was designed before synthetics came out. Ur just throwing money away

nonsense

synthetics have better temperature ranges and have more base stock and less viscosity modifiers as a result. nothing wrong with synthetic in an M20.

if your old seals leak after changing oil, the only thing that was keeping them from leaking before was all the crud built up on them.

also do some time searching on ZDDP. Rotella doesn't have nearly as much zinc as people think. it's also formulated for diesel engines, entirely different application

[SpecM]

I'd run 15w40 in everything I've got if it were easier to find. It's tough to find a place that consistently has 15w40 in stock here.

Get some Shell Rotella, its easy to find

I've been running it the last 4 changes in my m20 and I love it

[whiltebeitel]

can't switching from a conventional to synthetic or vice versa cause leaks or seal damage or something?

I've heard that old seals (cork, etc) can be more prone to leaking after switching to synthetic. YMMV. My car hasn't leaked any more than before (if anything, less) since I switched.

Rotella T is nice because of all the zinc in it. Zinc is nice on bearing surfaces, often recommended for freshly-rebuild engines (and all the e36 guys run it to keep the valve-tick down when they beat the piss out of their cars)

[pporcaro]

i would never use mobil one in my car.... ever

[delfin]

20w-50 is your best bet. It was pretty retarded to use synthetic.

I use Kendall.

[reelizmpro]

Yeah, I've read a lot of good things about Delo 15w-40 heavy duty oil. It's a diesel oil but it can be used in a gas engine and it's cheap! I also want to throw in Shell Rotella T synthetic 5w-40. Great oil at a great price.

[rThor432]

I just did a change to Delo 15-40.

Nice and quiet, I will see how it hold up as I only have 3 more changes before 300,000

I'd run 15w40 in everything I've got if it were easier to find. It's tough to find a place that consistently has 15w40 in stock here.

what about an m10 with 120k

Same as the M20.

[retardotyler]

[q