synectic/15-40
Post Fiend
Joined: Jun 2006
Posts: 5,497
Likes: 7
From: Central, Al
Why go back? the 5W40 has been approved for year round use, but if you want to switch there wont be problems. Just remember that there will always be a little of the old left in the HPOP System.
Senior User
Joined: Aug 2006
Posts: 127
Likes: 0
From: Maryland, WVU
iv been wondering the same thing, i live in Md, Wv and have been running the 5-40 shell oil for the winter, need to change it an was not sure if I should go to the 15-40 dino shell oil or keep with the syn. oil...any opinions? thanks
-Kurt
-Kurt
Post Fiend
Joined: Sep 2006
Posts: 7,426
Likes: 6
From: Sioux Falls, SD
You can keep running the 5W-40 all year round.
5W-40 and 15W-40 are both 40 weight oils once the operating temperature is reached. When the oil is cold (at startup) The 5W flows more freely than the 15W thus making startup easier.
99 7.3 towrig - I'de stick with the 5W-40 synthetic, it has shown better used oil analysis results than the dino 15W-40.
5W-40 and 15W-40 are both 40 weight oils once the operating temperature is reached. When the oil is cold (at startup) The 5W flows more freely than the 15W thus making startup easier.
99 7.3 towrig - I'de stick with the 5W-40 synthetic, it has shown better used oil analysis results than the dino 15W-40.
Last edited by white Buffalo; Apr 8, 2007 at 04:28 PM.
Senior User
Joined: Dec 2003
Posts: 331
Likes: 1
From: fl
i just changed to 5w 40 Syn. and I live in FL
http://theoildrop.server101.com/foru...e=0#Post851439
http://theoildrop.server101.com/foru...e=0#Post851439
Post Fiend
Joined: Feb 2002
Posts: 10,600
Likes: 3
From: Carhenge
I run Delo 15w-40 in the summer and Rotella T 5w-40 in the winter on 10,000 mile OCI, no harmful effects as far as switching back and forth. I change back to Delo in the summer because I get lower iron wear with it and it's cheaper, but the rotella makes it start so much better in the winter.
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Post Fiend
Joined: Sep 2006
Posts: 7,426
Likes: 6
From: Sioux Falls, SD
Originally Posted by clux
I run Delo 15w-40 in the summer and Rotella T 5w-40 in the winter on 10,000 mile OCI, no harmful effects as far as switching back and forth. I change back to Delo in the summer because I get lower iron wear with it and it's cheaper, but the rotella makes it start so much better in the winter.
If you can find Schaeffer's 15W-40 7000 series(synthetic blend) or 5W-40 9000 series (full synthetic) in your area you might want to give it a try. I found it to yield excellent iron wear numbers just like when I used to use Delo 400. The key to the better iron wear is the better base stock oil & Molybdenum that Delo 400 & schaeffer both use.
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Post Fiend
Joined: Feb 2002
Posts: 10,600
Likes: 3
From: Carhenge
Originally Posted by white Buffalo
Clux,
If you can find Schaeffer's 15W-40 7000 series(synthetic blend) or 5W-40 9000 series (full synthetic) in your area you might want to give it a try. I found it to yield excellent iron wear numbers just like when I used to use Delo 400. The key to the better iron wear is the better base stock oil & Molybdenum that Delo 400 & schaeffer both use.
If you can find Schaeffer's 15W-40 7000 series(synthetic blend) or 5W-40 9000 series (full synthetic) in your area you might want to give it a try. I found it to yield excellent iron wear numbers just like when I used to use Delo 400. The key to the better iron wear is the better base stock oil & Molybdenum that Delo 400 & schaeffer both use.