What Oil to use?

jorian · 11-07-2004, 10:29 PM

My 87' has 106K miles on the clock and runs well. No leaks or smoke. I live in Vancouver where it is getting colder. Will get down below freezing. What oil should I run ie: Brand & Weight?

Thanks.

jmohn · jmohn's Garage

Any quality brand. Folow the viscosity recommendation in the manual (minimum is 15-40, IIRC).

Jerry M
'78 SC

Wil Ferch · 11-08-2004, 05:25 AM

For your conditions....espcially regarding low temp operation... I would try Shell Rotella-T Synthetic 5W-40. In my own experience it has not caused ( allowed?) the leaks I got in cold weather with Mobil 1 15W-50.

Wil

RickM · RickM's Garage

I'd go to a synthetic if my car was operated is very cold temperatures. The flow characteristics are superior to dino oil an very low temps.

Some, however, report leaks with the use of synthetic. I haven't had that problem.

masraum · 11-08-2004, 06:29 AM

It depends on if you'll be driving in cold weather and how much. If you are going to be driving in sub freezing weather then I'd go to a 5W30 synthetic oil like Mobil 1.

jorian · 11-08-2004, 08:15 AM

Thanks for the replies. I will be driving a couple of days per week - no snow no heavy rain. I'll try the Shell.

Cheers.

Wil Ferch · 11-08-2004, 09:18 AM

Jorian:
some more info....I found the Shell doesn't leak like the Mobil did in cold weather.... but this could be because the Mobil is a "true" synthetic ( using PAO base-stock)....and it's *possible* that the Shell is a hyper-refined ( cracked) oil that is so highly refined...it's allowed by the Gov't to be sold as "synthetic". I haven't been able to verify this 100% but all indicators are there.

So.....we have nearly true synthetic perfomance...a nice wide 5-40 weight range to cover all temps...and no leaks. Good stuff so far...

Wil

jorian · 11-08-2004, 09:26 AM

Wil,

Sounds like the ticket.

Jorian

markmaunz · 11-08-2004, 10:21 AM

Are you guys changing oil every 3K or 5K or what, and why? thanks, Mark

Wil Ferch · 11-08-2004, 10:26 AM

look here....best factual web site I found yet on oils.

Motor Oil Web site

Wil

Bill Verburg · Bill Verburg's Garage

I have used the Shell 5/40 synthetic and liked it, but the old standby M1 15/50 flows very well at low temps as well, You shouldn't hesitate to use either.

jeff1hughes · jeff1hughes's Garage

I don't think Rotella is synthetic at all.

Bill Verburg · Bill Verburg's Garage

Quote:

I don't think Rotella is synthetic at all

Go look, you will findat least 2 versions on the shelves

jhawk1000 · jhawk1000's Garage

Look at it this way-----if you finally get the ultimate oil---one that will last forever and protect the engine forever---what will some of you do in your spare time? No more engine overhauls, no more worrying about choices. Life might just not be that good if perfection comes about.

I did NOT understand much of the 177 pages but I often wonder about religious tracts in the middle of technical papers.

Mel

jhawk1000 · jhawk1000's Garage

OOPs, I did not understand the Oil Bible that the previous thread was about. Sorry but I read the Oil Bible from a link in the previous quoted thread and probably should have replied there.

Mel

unclebilly · unclebilly's Garage

I like Chevron Delo 400 Synthetic 5W40. It's great stuff, it's only $18 per US gallon at UFA - I run it in everything I own. I called Chevron and asked if it would be OK for the air cooled Porsche, the applications engineer that I talked to said that if he had a 911, this is the oil he'd use.

Wil Ferch · 11-09-2004, 05:15 AM

OK...let's compare Shell Rotella-T synthetic 5W-40 with DELO syn 5W-40

Shell....VI= 176, pour point= -40 degF, Flash point= 475 degF, HT/HS= 2.90, NOACK volatility= 13.0, TBN = 10.0

Delo is very similar but has lower flash point ( 449 degF) but has higher TBN of 13.0....so it can stay in the engine longer by having more acid fighters, etc.

For our hot running air cooled motors, I would look for the best flash point, the highest high temp shear characterisitics ( HT/HS)...and if I could get it....low NOACK since this is the % burn off under extreme conditions, and is a direct indicator of oil consumption. I wouldn't worry too much on TBN, since we tend to change oil frequently. If an all-year round car that sees cold weather, i would look to Pour point ( PP), and CCS...a cold weather index.

I don't think that flash point can be under-estimated. Normal ( mineral) oils commonly have 420-440 degree capability, and some "true" synthetics....especially the straight weight versions, get into the medium 500 degree range. I beleive that the oil temp we "read" from one sensor location is not a good indicator of how hot it can really get in local spots in the engine ( top ring area, etc)...so high FP would be important IMHO.

Wil