Switched to 5-30 Mobil 1

[AdamF 88iS]

and if your talking about motors that are built for mass production then i must ask you what motor other then high end sports cars are not built for mass production? for that era these engines are pretty high tech, of course they're out dated now but for their time they were pretty damn good.

For their time, yes. But remember, in their time when the M20 was designed, these thin ass multi grade synthetic oils weren't generally avalible. Newer Aluminum block engines are made to work with these oils to save gas. Is that really what's best for the engine? Probably not, but as long as it makes it thru the warranty period and makes the car look better on paper for sales thats all the manufacturer cares about.

And as far as 'what difference 10 index points makes' since we are only talking from 30 to 50, 10 index points is half of the entire scale here; pretty significant if you ask me.

I give up on you guys, I seriously do. You have a couple highly experienced mechanics who work on these cars day in and day out giving you their advise in this thread but you all choose to go by some crap you read in random places on the internet, including Mobile 1's own website; don't forget they are out to sell you oil, not be your pal.

[arsevader]

For their time, yes. But remember, in their time when the M20 was designed, these thin ass multi grade synthetic oils weren't generally avalible.

Exactly and the synthetics that were available were pretty piss poor and often did more harm that good.

And as far as 'what difference 10 index points makes' since we are only talking from 30 to 50, 10 index points is half of the entire scale here; pretty significant if you ask me.

Very sinificant. It's the difference between a correct vicosity and a wrong one.

[quote]I give up on you guys, I seriously do. [quote]

I gave up on most internet boards a while ago but for some strange reason I keeping getting drawn into these moronic discussions.

James

[joecoolinatl]

ok i live in atlanta. summer temps generally range from 70-75degrees F ( 21 celsius) to 100 F at the hottest (37.7 celsius)

for a daily driven e30 2.7 eta auto with over 200K miles. probaly will be 300K by end of year, whats the best oil?
right now its got mobil 1 10w30 in it. and i think im using a quart of oil about every 3000-4000 miles.
thanks guys

[arsevader]

ok i live in atlanta. summer temps generally range from 70-75degrees F ( 21 celsius) to 100 F at the hottest (37.7 celsius)

for a daily driven e30 2.7 eta auto with over 200K miles. probaly will be 300K by end of year, whats the best oil?
right now its got mobil 1 10w30 in it. and i think im using a quart of oil about every 3000-4000 miles.
thanks guys

I would use Mobil 1 15W-50.

James

[AdamF 88iS]

ok i live in atlanta. summer temps generally range from 70-75degrees F ( 21 celsius) to 100 F at the hottest (37.7 celsius)

for a daily driven e30 2.7 eta auto with over 200K miles. probaly will be 300K by end of year, whats the best oil?
right now its got mobil 1 10w30 in it. and i think im using a quart of oil about every 3000-4000 miles.
thanks guys

I would use Mobil 1 15W-50.

James

:up:

[joecoolinatl]

cool thanks!
also i had my valves adjusted right when i did the last oil change. they are still a lil noisy, i know all 325 e30s are but would changing the oil lower the noise as well?
thanks!

[nickmp0wer]

i have noise in my timing chain and im hopping switching to 10w-40 will fix it :?

[arnoldgtr]

The owner's manual and Bentley (P. 2-9) both have a temperature-viscosity scale. For example, 10W-40 is only good from -20 to 50 degrees F. The ONLY oils recommended for 80+ degree temperatures are 15W-40, 15W-50, and 20W-50.
E30 engines are built looser than modern engines. I would never use a 5W oil in an E30.

[parkerbink]

I cannot believe a simple question became a shitfest. Same question poosted on e30tech was answered & no one called anyone else names. I asked before I switched & was told both by BMWNA & Mobil to use this oil. As to the 5 weight since the temp never gets below 60 the oil never gets below 30.

P.S. I replaced it with less than 20 miles on the oil.

[bmwdude]

One will ask 10 different respected technical advisers on the subject of oil recommendations, and will end up getting over 5 different answers.....and even in the year 2005, you may even get 1 or 2 that will recommend mineral oil over synthetic.......

Most German cars to my knowkledge seem to like a slightly thicker oil, as opposed to Japanese cars. As far as E30's M20 engines are concerned, I try to base my desicion on what oil to use, based on my driving habits and ambient temperature. Not taking into account here, an engine that has over 500 000km with some blow by.

For typical summer temperatures, I personally use synthetic a 15W-50. This is from someone who redlines the engine on a daily basis. However, perhaps, and I won't insist here, it MAY make sense, for someone who uses his E30, in a very gentle, family oriented manner, on a daily stop and go basis, to use a 10W-40 perhaps? Someone who never revs passed 4500rpm lets say. A typical conservative father/mother, who uses his/her E30, or even E34 M20, as a family car and nothing else.

[joecoolinatl]

im going to pickup some oil on tuesday. just wondering, someone else told me to get 20-50.... and i know you guys said 15-50
whats the difference?
and also what exactly do the numbers mean, i used to know but mymind is at a total blank right now

[arsevader]

im going to pickup some oil on tuesday. just wondering, someone else told me to get 20-50.... and i know you guys said 15-50
whats the difference?
and also what exactly do the numbers mean, i used to know but mymind is at a total blank right now

15w-50 or 20W-50 would be perfectly fine.

A simplified explanation is as follows:

The first number represents the equivalent straight weight oil when cold. ie. the first number is what the oil will be like upon start up. THis is why you want a lower number when the weather is cold. Here in Canada I use 5w-50 in the winter because it gets really cold.

The second number represents what the oil will be like at operating temperature. That is why I use 15w-50 in the summer.

Both oils have a second number of 50 because once the car is warmed up you want a highly viscous oil running through the engine for protection and the ambient temp has no eefact on it.

Another thing to take into account is that the greater the range in the numbers, the quicker the oil will move its index towards the first number as it breaks down. Therefore you really want to get an oil that works well for your ambient temp for startup but has a narrow index range. ie. 15w-50 is going to break down slower than 5w-50.

James

[nickmp0wer]

well i switched to 10w-40 from 5w-30 in my m42 and it seems like the timing chain rattle is gone so far. the question is did i damage my engine at all? when i took out the 5w-30 i could see some really tiny specs floating on top of the oil. not metal i hope

[arsevader]

well i switched to 10w-40 from 5w-30 in my m42 and it seems like the timing chain rattle is gone so far. the question is did i damage my engine at all? when i took out the 5w-30 i could see some really tiny specs floating on top of the oil. not metal i hope

Unlikely, you'd probably not cause any damage that quickly. The only way to really check is to have the oil analysed.

James