Best oil for 993???
#1
Escapee
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Here is the environment variables:
Canadian summer - not too hot, not too cold
Drive at relatively high RPM (aggressive)
60K on the clock, great shape, no leaks
Get stuck in traffic jams occasionally in hot weather
My last 911 was a 3.2l with 140k on it. I used 20/50 and Lucas to minimize the smoking/leaking.
1) Do I use a heavy weight oil like 20/50?
2) Do I use synthetic over petroleum?
3) What makes are preferred? Mobil 1, Castrol, Valvoline, Penzoil?
Thanks,
Canadian summer - not too hot, not too cold
Drive at relatively high RPM (aggressive)
60K on the clock, great shape, no leaks
Get stuck in traffic jams occasionally in hot weather
My last 911 was a 3.2l with 140k on it. I used 20/50 and Lucas to minimize the smoking/leaking.
1) Do I use a heavy weight oil like 20/50?
2) Do I use synthetic over petroleum?
3) What makes are preferred? Mobil 1, Castrol, Valvoline, Penzoil?
Thanks,
The following 2 users liked this post by Robin 993DX:
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#9
RL Technical Advisor
#10
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Originally Posted by Steve Weiner-Rennsport Systems
"Porsche’s recommendation in hand, our analysis found that all recent SL formulations of Mobil lubricants tested, including Mobil 1, have similar 0.14% Zn and 0.14% P content, which we think is a good thing, but looking closer, Mobil 1 0w40 had somewhat less Zn and P, but still above 0.10%. Even more disturbing, Mobil 1 15w50 now is an SM formulation, with only 0.09% to 0.10% Zn and P when it's previous SL formulation had excellent levels of both Zn and P! It is worth noting that Mobil 1 V-Twin 20w50 retains an SG classification with unchanged Zn and P levels close to target 0.14% Zn and P, but for most users, a 20w50 for year round use is unacceptable for cold-startup protection."
.... is one of the reasons I've been motivated to consider Mobil Delvac 1 5W-40 for the 993: this is a full synthetic primarily formulated for class 8 diesel specs; however, it also carries a SL rating, and is equally rated for high performance gasoline motors by Mobil.
There is some long term analytical data supporting excellent results with this oil in 928 service ..... but I'll have to dig back to see what Zn and P levels are.
Doug Hillary is the author of those informative evaluations ... search the 928 archives if interested. Here's a link to Dougs Report #11 .
Last edited by Garth S; 03-01-2007 at 10:02 AM.
#11
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Another oil discussion, which is great reading as we all have opinions. I am a firm believer to have quick oil flow at start up as that is when most wear occurs, especially if car sits for a few days. That said I found 0-40 works best for me. After reading what Doug Hillary wrote, who I view as an expert oil engineer, I probably will change to 5-40 Delvac, or Rotella in the future. In certain cases with oil, it somewhat academic especially if oil is changed regularly, proper driving habits, like warm ups are done properly.
#12
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There are strong indications that Mobil has changed the basestock for Mobil 1 to a Group III rather than the PAO formulation that they had used in the past. The proof is in the Used Oil Analysis and I have not seen any M1 15w50 results that are worth much lately.....You can do better by selecting another oil from the article that Charles put out.
#14
Weathergirl
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but I'll have to dig back to see what Zn and P levels are.
![](http://www.rallystuff.com/images/blackstone_voa_delvac1.gif)