Converting to synthetic oil

[Sirius600]

After owning my ti for about 3 months, I'm finally coming up on my first oil change (teehee). The dealer had used regular 20W50 fossil oil, but I've been thinking about converting the engine over to full synthetic oil.

My main goal is to get a little more performance and life out of my ti's engine. Could anybody give some pointers on the changing process and any recommendations on new oil weights? I was thinking of Mobil 1 (if i can afford it) 15W50 or 20W50.

What do you think?

P.S. I'm in Los Angeles, so the temperature never falls below 50 F, but can get past 100 F in the summer.

[brucelee]

Originally Posted by Sirius600

After owning my ti for about 3 months, I'm finally coming up on my first oil change (teehee). The dealer had used regular 20W50 fossil oil, but I've been thinking about converting the engine over to full synthetic oil.

My main goal is to get a little more performance and life out of my ti's engine. Could anybody give some pointers on the changing process and any recommendations on new oil weights? I was thinking of Mobil 1 (if i can afford it) 15W50 or 20W50.

What do you think?

P.S. I'm in Los Angeles, so the temperature never falls below 50 F, but can get past 100 F in the summer.

I live in San Diego and use Mobil One 15-50. Good stuff. If you car has tons of miles or you suspect that it is internally a bit dirty, you can simply run the new syn for a 1000 and then do another oil change with fresh syn.

If not, just change it and go. I change every 5K with Mobil 1, as it is such a great oil.

Don't forget Mobil 1 ATF in your trans. and Mobil 1 diff fluid (75-90).

Good luck

[clex2]

15w-50 seems a bit thick for the 318ti motor. 50W is good for high heat/stress, which the m42/m44 does not usually see. I ran 15W-50 in my aircooled 911 (15 quarts per oil change, mind you) and I tracked that car frequently. I think you will loose a few MPG and not gain much from the thicker viscosity. Winter is coming, so if you live in a colder climate, you'll want something with a lower cold viscosity rating, like 0W or 5W. You should know that Mobil 1 makes a 0w-40 fully synthetic oil, "european blend" which is just marketing speak, but I think this is pretty ideal for all around use. It comes with a black label, green and red are the other color for the other viscosities. Not every place sells it, but it's out there. Just my $0.02. Oil is a very personal thing, but just use a repuatble brand fully synthetic and you should be good. I've used Mobil 1 in my ti since new and it reuns like a champ with 108,000 miles. At 97,000 miles, the leakdown test was perfect.

[brucelee]

I had an oil engineer that works for Mobil tell me off the record that he would not use 0-40 in his wife's sewing machine. Of course, where I live, 15-50 is the real deal to handle the heat and it never really gets cold in winter so the heavier Vis is appreciated. Moreover, that little 4 cylinder is working pretty darn hard to risk losing the VIS at higher RPMs.


If we had cold winters, I would use 10-30 Mobil green cap and then back to Red Cap in summer.

[Sirius600]

Originally Posted by brucelee

I live in San Diego and use Mobil One 15-50. Good stuff. If you car has tons of miles or you suspect that it is internally a bit dirty, you can simply run the new syn for a 1000 and then do another oil change with fresh syn.

If not, just change it and go. I change every 5K with Mobil 1, as it is such a great oil.

Don't forget Mobil 1 ATF in your trans. and Mobil 1 diff fluid (75-90).

Good luck

Not to get off topic, but should i ever completely change out the transmission fluid, or can i just add some ATF to the system. I'm not sure what brand or type of fluid is currently in the tranny.

[brucelee]

Originally Posted by Sirius600

Not to get off topic, but should i ever completely change out the transmission fluid, or can i just add some ATF to the system. I'm not sure what brand or type of fluid is currently in the tranny.

The manual and the automatic both take Dexron ATF and both can and should be changed.

I have the manual trans and drained it and replaced it Mobil 1 ATF. Shifts much more smoothly now.

PS-install an M3 shifter for much shorter shifts.

[aceyx]

i'm really surprised your dealer used 20w50 dino juice, but it's probably a location thing.


anyway. i've been running mobil 1 5/10w30 (depending on the season) since 36k miles. at 130k miles, the motor still runs as if new. a slight idle problem, but that's due to a problem with the vacuum system. the rest of the car is falling apart.

i change the oil every 4500 miles, and if i've just ran a long trip (school -> home -> back ~ 2000 miles) i'll change it just because it's been at high rpms for so long. i like to drive fast, i bet most of us do.


doing it yourself costs about an hour and $25 or so. walmart (at least around here) has 5qt jugs for $20, and you can snag filters for cheap if you get like half a dozen. most places won't charge less than $50 for a synthetic oil change. and if you do it at the dealer, make sure you know what oil you're getting. i think bmw-branded synthetic is castrol, which is also another good brand.


for tranny and differential, i use redline synthetic because i don't muck around with it that often (every 30k or so? depends on how lazy i am). i drain, then use a suction pump to get out whatever's sitting in the bottom, then fill back up to the top bolt hole.

for anyone that's not done tranny/differential, take out the TOP BOLT FIRST. you gotta make sure you can fill it back up before you drain. if it doesn't come out, best take it to a shop (unless you know what you're doing with the penetrating spray and/or blowtorch).

[Sirius600]

So no special procedures need to be taken when switching from fossil to synthetic oil? Just switch it like a normal oil change?

Also, will any oil filter get the job done, or should I buy one made specially for synthetic oils?

[1996 328ti]

Buy the filter made for the car. It is cheap enough from BMW.
It will come with a new crush washer and o ring.
Just did oil changes today, the ti and the Mini.

I now change my oil every 9K and just the filter every 4500.