depending on the mileage i wouldnt switch to synthetic... your seals will start leaking

 

For you I'd say dino oil:

20w-50 in warm months
10w-40 in cold months

But you maybe could get by with 20w-50 all year round.

+1 on leaky seals with synthetic.

+1 on no synth.

10w/50 in warm months.

 

For you I'd say dino oil:

20w-50 in warm months
10w-40 in cold months

But you maybe could get by with 20w-50 all year round.

+1 on leaky seals with synthetic.

 

The previous owner said that he put synthetic in it.
From my knowledge after switching to synthetic, you can't turn back to regular oil.

What should I do ???

 

what about royal purple? buddy uses it in his 302 roller motor, loves it. i am also looking for the best replacement oil. mine came with penzoil in it :bawling:, nevermore:eeps:

 

what about royal purple? buddy uses it in his 302 roller motor, loves it. I am also looking for the best replacement oil. mine came with penzoil in it :bawling:, nevermore:eeps:

I saw it for 8.56 a qrt that is nuts! I only use purple in my transmission. I personally use 10w30 mobil 1 synthetic with no leaks. I did rebuild my eta though...

I change conventional oil with Castrol GTX or Pennzoil 10w30 and have no issues. It really does not matter TOO much, you could go 3k miles and change it every time with the Walmart Super tech brand. Most of the time when you spend more on oil it is made to not break down in heat as fast. But ever 3k is dandy and you could run the Super tech and never have an issue.

In the end it falls onto what are your plans for it? Racing I advise replacing seals and running synthetic oil because it does not break down. I tested it, I went 3,500 miles on Pennzoil conventional 10w30 and it took me around 10,000 miles for the mobil 1 10w30 to reach the same point of break down(dark oil). The mobil 1 does work and worth EVERY cent in the long run.

So if you want to take the time scrub the engine CLEAN then change it with Mobil 1 and check it in 1-2 days and see if there is leaks. Then replace the gasket and you are good to go for anything you want to throw at the engine.

 

Valvoline 20-50/summer, 10-40/winter

 

No way. Where have you been? :rofl:

 

I use Royal Purple 20w-50 year round never had a problem owned the car like 3years plus the oil seems to last longer than regular run of the mills brand oils.

 

Mike Miller recommends 10w even in warmer climates due to its ability to flow when the engine is cold. According to him, the oil galleries of high-mileage engines are sometimes narrower due to surface build-up.

I don't see any benefit to running 20w/50 over 10w/50 except that the 20w is more readily available.

 

I don't see any benefit to running 20w/50 over 10w/50 except that the 20w is more readily available.

Keeps leaks to a minimum

 

the glass isnt half full nor half empty. Its just twice the size it needs to be :thumbup:

 

I dig it

 

I had my oil changed recently and the service center put semi-synthetic 5w-30 in there. I'd like to switch back to 10w30 or 10w40, which is what I've always used..can I do this or have I screwed myself with the synthetic?

 

its a blend. the synthetic blends are "made" to clean higher milage motors and help improve lubrication and fuel eco. but the issue people run into, is they put the blend in and they start getting leaks or burn more oil because it is thinner than your basic dino oil. no you didnt screw yourself. next oil change just throw in what you want.

 

Thanks, Downhiller!!

 

she's tore down right now. will make decision soon...thanks...no racing planned, just cruisin':bigpimp:

 

i mean i run mobil 10w30 synthetic but like e30F34R im running all new gaskets so.. no leaks

 

that will be my case...how often are you changein'...also filter...what is best for synth?

 

umm i changed it like 500 miles after switching, now i dont let it go past 4000 before a change, i know you can let it go longer but im anal about oil. LMAO
I use the fram extended gaurd filters in all my cars

 

was figuring on 5-6k mi, but 4k could only be better...how is synth on the gaskets? with smaller molecules i'm thinking it finds a place to leak way sooner than normal. do you have to stay on top of torx...:dunno:

 

if youre rebuilding the motor and replacing all gaskets and seals (you better) you wont run into any leaks. the only reason why gaskets leak when you change to a synthetic is because the carbon or sludge build up on gaskets gets cleaned out and makes a small opening for the oil to get out

 

i did re-torque my head at 500 miles when i changed the oil the first time after switching.. but it doesnt leak at all...

and my jeep doesnt leak... (it marks it territory) with 20w50... and diff fluid

 

by the time i finished my last engine, (327) the only parts that were not new were the crank and pistons. i get a little carried away. all new seals and gaskets of course. new head bolts $18...why not. oil pump $149...while i am this deep why not. the project may drag on longer than planned, but i don't want to go this far again. when this re-build dies (hopefully not for 100k+) a swap will be in the forcast. ...:smokin:

 

ok, the problem that people think is that once you go synthetic you cant go back to mineral oil, that no longer holds true, people were just all hyped up back when synthectic oil was introduced and it was leaking all over the place becauseit was a much thinner oil than the traditional mineral oil that people were running in there cars.


The truth is that most modern mineral oils and synthetic oils for that matter have come a long ways since they were first marketed, they are simply entirely concocted oils from scientist, they are designed to keep seals as they are, no to shrink them as they used to. they will work in cars old and new.

the thing is to make sure you BMW doesnt leak oil now, if it does, then i would go with the regular oil of the weight 10w-30 or 40

another option is to use a heavier weight synthetic oil if it is leaking.

But if it isnt leaking (that you know of) then you will have no problems switching back to regular oil. the modern syn oil that is in your car now has done nothing to your cars seals which are made up of some elastic materials (therefore the strecthing and shrinking, this is what creates the leaks switching back and forth)


Of course i wouldnt go making a habit of switching back and forth, pick one and stick with it.


A prime example is when I used to run mobil 1 syn oil in my integra for years, but as i recently lost my job, i started using regular mineral oil to save money, and my integra has leaked a drop, been going on a year now.

I personally use Lubro Molly full synthetic oil in my E30, works great.

 

ok, the problem that people think is that once you go synthetic you cant go back to mineral oil,

have to stop you there. patrol based oil is a whole other level then mineral oil. mineral and synthetic in general are the same thing, just the base is different. amsoil is a mineral based oil for example. it is a true 15k miles oil used in vws audis and porsches (mainly in theyre higher end cars for break in, then go to a castrol syn). another application is the compressor in your basic household ac unit. it last up to 25 years before breaking down (with proper running ac)

yes the newer oils have simular qualities, but its the base that it is designed with. for instance, go to a shop, a quick lube place, and ask if they have any eco-oil. its an oil based off refined used oil with new additives. its the worst thing to put in your engine. it has no viscosity to it and it breaks down quick. you can feel it when its new. take a dab and rub it between your fingers. do that with all types. youll find that the syn and mineral feel the smoothest where the patrol is thick and the eco is like water

 

Cool, thanks for the feedback. I think I'm going to go back to 10w40 in general. My car seemed to run a bit more efficiently on that. What's weird about the 5w-30 is that my car seems to consume it very quickly--like 1/2 qt. every 300 miles. My car generally used 1/2 qt or less every 1000 mi on 10w40. I mention this in case it's something I should be thinking about.

 

any feed back on 15/40 desiel?

 

i ran rotella 15w40.