Synthetic Oil
Senior User
Joined: Aug 2006
Posts: 307
Likes: 0
From: Siesta Key, FL
Head on over to the forums at - Bob is the Oil Guy You'll find plenty of discussions on the 7.3 and 6.0 there. Depending on your driving habits and the mileage, you may find many there that will tell you synthetic is just a waste of money. With that type of mileage though, I'd suggest getting a Used Oil Analysis from Blackstone Labs (about $25) and you'll find out whats really going on in that engine. There is a forum on there that posts some amazing analysis results from oil out of high-mileage 7.3's. Good luck!
Lead Driver
Joined: Jan 2006
Posts: 7,308
Likes: 250
From: Hartford, WI
Head on over to the forums at - Bob is the Oil Guy You'll find plenty of discussions on the 7.3 and 6.0 there. Depending on your driving habits and the mileage, you may find many there that will tell you synthetic is just a waste of money. With that type of mileage though, I'd suggest getting a Used Oil Analysis from Blackstone Labs (about $25) and you'll find out whats really going on in that engine. There is a forum on there that posts some amazing analysis results from oil out of high-mileage 7.3's. Good luck!
Senior User
Joined: Aug 2006
Posts: 307
Likes: 0
From: Siesta Key, FL
I have no doubt. And I'm sure less wear on the starter and batteries. However, my comment was to the OP who lives in FL, which is where my Ex does most of it's service.
Cargo Master
Joined: Jul 2009
Posts: 2,885
Likes: 26
From: Chino, California
Synthetic oil viscosity stays more constant in a wider range of temperatures. I noticed that pouring syn at ambient temp, it flowed quicker than dino oil at the same temp. When warmed up, dino oil was flowing like the syn.
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Lead Driver
Joined: Jan 2006
Posts: 7,308
Likes: 250
From: Hartford, WI
Isn't Rotella 5W40 whereas dino is 15W40? If so, that might explain the cold difference.
Hotshot
Joined: May 2005
Posts: 13,484
Likes: 42
From: Stevens Point, WI
I am with the waste of money group. We run our diesels all winter and never plug them in while running 15w40 and no problems. Two of our diesels have over 400K miles on them now and running as good as always. In fact we are having more problems with salt ruining our trucks before the drivetrain going out...
Lead Driver
Joined: Jan 2006
Posts: 7,308
Likes: 250
From: Hartford, WI
I am with the waste of money group. We run our diesels all winter and never plug them in while running 15w40 and no problems. Two of our diesels have over 400K miles on them now and running as good as always. In fact we are having more problems with salt ruining our trucks before the drivetrain going out...
Hotshot
Joined: May 2005
Posts: 13,484
Likes: 42
From: Stevens Point, WI
Well, you know the weather we get, both diesels have started every day all winter long since they were new. One is a 94.5 IDI turbo and the other was a 86 6.9 IDI. The 86 however has been retired for about 5-6 years now with about 460K miles on it. The 94.5 is still is service.
Being started every day may have something to do with it. Probably don't chill down to absolute ambient temp by the next morning.
Senior User
Joined: Nov 2010
Posts: 450
Likes: 1
I think running them every day also helps keep the batteries charged. When it's that cold out they don't hold a charge well. So the combination of the two must be helping you. Do you park them inside? Being out of that cold wind helps too, doesn't even need to be heated.