Safe, I hope, Oil Question
 

1990 300D 2.5L Turbo.

I live in the SF Bay area.

Temperature range is 40 F to 100F.

What weight (5W-30, 20W-50, etc) do I use?

Thanks.

Isn't there a page in the owner's manual dedicated to this?

15w40 or 5w40 would work well. 5W30 will be too thin, and most commonly available 5/30s are not diesel rated.

-J

There is a page in the owner's manual that addresses this question. As far as types of oil, I am going with Amsoil 10W40 Premium Synthetic Oil with boosted levels of ZDDP for extra lubrication. However, I also believe that the Lubromoly oils (available at NAPA) are on par with Amsoil, both are amongst the top five performing oils.

If you guys thing there are oil wars here you should hop on over to TDIClub. Numerous tests have shown Rotella T6 5w40 to be an excellent oil, and a value that is hard to beat. It's an easy recommendation for me to make.

http://forums.tdiclub.com/showthread.php?t=325214

-J

Of course - but things have changed in 20+ years.

Or maybe they haven't.

PS - I got 400K running Castrol (mineral) 20-50 on my prior car but then I come here and I encounter a wide variety of thought.

So I asked.

They didn't have Rotella T6 back then.

I'm going to have start looking for that stuff. 5W-40 is just what I need.

So it seems like a good question for me to ask.

Any advice which stores for purchase?

Mau Mart and AutoZoo have it.

-J

I call my local WalMart and ask but no one answers the phone?

I'm buying them locally at $28/gallon.

How terrible is that?

For OM617.952s, however?

I can't get my head around whether 5w40 oils are ok or not for the older motors.

And this would be surprising, why ? :inquisiti

Yes oil rated 5 40 is good for any diesel as long as it is Diesel rated. I really like Mobil 1 Light truck and SUV Diesel in 5/40 for my 300D. I use it all year, great for hot weather on the 40 side, great for cold starts on the 5 side. I have never had trouble starting my 300D since I began using it about 4 years ago.

FYI
 

Rotella T6 5w40
http://www.shell.com/home/content/rotella/products/t6/

http://www.google.com/search?q=T6+5w40&rls=com.microsoft:en-us&ie=UTF-8&oe=UTF-8&startIndex=&startPage=1&rlz=#q=rotella+5w40+synthetic&hl=en&rls=com.microsoft:en-us&prmd=ivnsfd&source=univ&tbm=shop&tbo=u&sa=X&ei=G1RATrDeD4WIsQLfu6Qw&sqi=2&ved=0CHcQrQQ&bav=on.2,o r.r_gc.r_pw.&fp=cb18799be3bd9f8c&biw=1280&bih=863