Sythetic Oil in older engines

[kearnyme]

I've heard that switching to synthetic oil in an older engine can cause leaks due to the fact that synthetic oils have detergents in them. I was told that this was not a good idea with older rubber seals, is this true? My engine has never been rebuilt and it has over 150,000 miles on it. The person who had it before me apparently changed the oil religously and the engine has had no problems. My mechanic said that it was remarkably clean on the inside when he changed the timing chain. Do you all think switching to synthetic is even necessaryat this point?

[007ben]

you sure syntehcic wasn't being used before?

[kearnyme]

yeah, pretty sure I have all of the records. It looks like castrol was used for a while, but I'm using valvoline now. My cousin uses Mobil 1 in his Mercedes and it has about the same amount of miles on it as mine does. I think he switched to synthetic as well.

[Andrewsd1985]

Never heard of it being bad for an older engine. It could still have been synthetic if it was castrol.

[Mattitjah]

There are no detergents in synth. oil. If you change oil every 3k miles then using synth. oil is a waste. If you change every 5k-8k then synth. is the only way to go. I use Mobil1 15w50 every 6k miles. I use 15w50 because its often very hot down here in Louisiana and it is better for a car with "high" miles (100k +). You do not wan't the oil to run too thin.

[tico481]

I have a 95 325is here in Atlanta GA where it gets pretty hot sometimes. What grade of oil do you guys recommend I use?

[jllphan]

Originally posted by Mattitjah@Apr 29 2004, 03:24 PM
There are no detergents in synth. oil. If you change oil every 3k miles then using synth. oil is a waste. If you change every 5k-8k then synth. is the only way to go. I use Mobil1 15w50 every 6k miles. I use 15w50 because its often very hot down here in Louisiana and it is better for a car with "high" miles (100k +). You do not wan't the oil to run too thin.

That's pretty good advice, Tico :wink

[tico481]

Doesn't that just make me look really smart. Thanks for the advice though

[Kevin325i]

I also run the 15w50 mobil 1, but I plan to change at about 3-4k miles because i autocross the car and it sees some high revs on the track.

Kevin

[kearnyme]

Thanks Guys

[roguesniper1]

Originally posted by kearnyme@Apr 29 2004, 12:34 PM
My mechanic said that it was remarkably clean on the inside when he changed the timing chain.

Why the hell did you have the timing chain changed? Second, it is recommended to use same kind of oil all the time. Third, synthetic is only good if you are abusing your car or are too damn lazy to change it every 3k. I am quite lazy, but prefer to use mineral oil instead of synthetic and change it every 3k. Which is every month since, I drive close to 3200 miles in a month ghead ghead .

[kearnyme]

Man that sucks that you have drive so far.

[M3Daemon]

I live in a very hot area too. I've been using 15W-50 synthetic Mobil 1 for over a year now. Works great for me. The only disadvantage with that highly viscous oil is that it needs longer to achieve operating temp, but that's a minor moan.

Daemon

[Mattitjah]

Originally posted by Kevin325i@Apr 29 2004, 06:54 PM
I also run the 15w50 mobil 1, but I plan to change at about 3-4k miles because i autocross the car and it sees some high revs on the track.

Kevin

Good!!!

[Mattitjah]

Originally posted by roguesniper1+Apr 30 2004, 06:35 PM--></div><table border='0' align='center' width='95%' cellpadding='3' cellspacing='1'><tr><td>QUOTE (roguesniper1 @ Apr 30 2004, 06:35 PM)</td></tr><tr><td id='QUOTE'> <!--QuoteBegin-kearnyme@Apr 29 2004, 12:34 PM
My mechanic said that it was remarkably clean on the inside when he changed the timing chain.

Why the hell did you have the timing chain changed? Second, it is recommended to use same kind of oil all the time. Third, synthetic is only good if you are abusing your car or are too damn lazy to change it every 3k. I am quite lazy, but prefer to use mineral oil instead of synthetic and change it every 3k. Which is every month since, I drive close to 3200 miles in a month ghead ghead . [/b][/quote]
Mineral oil??? Synth. oil is regular ORGANIC oil where the hydro carbon-chains have been engineered, by heat and chem. reaktion, to evaporate the shorter links and break the longer links so that they all are the same length. Quite simple.