I've ran synthetic oil in my vehicles for years with great success. Better milage and longer change inteervals. I have been told, but by no one with any plauseable reason, that I shouldn't put synthetic in a CTD. I have a 2002 4x4 with 140,000 miles that I will use as a full-time hauler and work truck. I would like to hear from anyone using synthetic ar anyone with a good reason not to use it.
thanks in advance,

Cowboy

 

I don't think it is really a no-no. More like, unnecessary. With 3 gals of oil per change, synthetic is expensive ($75 currently)! RPMs for a diesel are lower than a gasser so I would expect that oil does not work quite as hard. I was told by many that if you replace regular oil in any old enough engine with synthetic, you are asking for leaks as the syn is slicker and will dissolve the sludge and creep out through seals that got hardened a little bit from the old age.
-P

 

I've been running it since my first diesel truck in 1989. Ran the same oil in the 89 for 4 1/2 years. Currently running 25000 miles on an oil change with dual remote filtration. You gotta do what makes you feel good and what you want to pay for.

 

I put in 5-40 syn at 500 miles and she runs just fine.

 

I switched from the normal 15-40 to Rotella 5-40 synthetic at 50,000 miles. Just about to turn 60,000 miles and changed out the 5-40 for another 3 gallons of the same. Walmart price for the oil is about $50, but by increasing the change interval from 5000 miles to 10000 miles, the cost is a wash. My original goal was to improve cranking in the winter, which was outstanding beyond my expectations, but found the improved fuel economy to be a worthwhile bonus. Looks to be about one mile per gallon.

 

There is no good reason not to use Syn....
It is better > on all point but price
It is more stable and will protect much longer than conventional oils.

You will hear lots of people tell you it is a waste of money and time... For them it probably is...
I am in the oil business and depend on my rig every day and lose money if it is down... I run Schaeffer Supreme 7000 15w40 and I run 10K miles... I take samples at all changes and everything is going great for my truck...
Don't just ask for opinions on an internet forum... and don't listen to salesmen... You will just get a bunch of anecdotal stories about what they have seen or heard of that can lead you in the wrong direction....
Get well documented information about what will fit your needs and go with it...

OG

 

Heck, if I can gain 1 mpg, I will switch to synthetic. I also like how it flows faster on a cold start. It kills me to watch the engine run dry for a few seconds when I first start it.

 

Cold and warm weather performance is what Synthetics are all about. I generally run 0W40 year around.

There is some very good oil info here (at least there used to be):

www.bobistheoilguy.com

 

I've experanced nearly the same thing. Finally this year changed over to full synthetic and the cold-start and initial running differances were enough to make me stay with it. I'll likley stick with 7500 changes as I just don't drive it that much.

Only negaitve I've understood is the *unconfirmed* possibility of seal/gasket hardening on older engines. With an older car it's likley best to stick with mineral oil, regular changes, and keep what you know works. For my truck I appreciated the better cold-start and smoother running in they synthetic oil provides.

 

I run syn in the wintertime for better starting. The better mileage and reduced wear are nice, but neither one would do me any good if the truck didn't start. I run Delo 400 dino in the summer.

 

like Dr. Evil I run 0-40 Esso full synthetic and It starts great in the winter and the oil press is there quick. I have been in South Dakota last year at 102 degrees F and never had a problem. I put it in at 1700kms or 1056 miles the first time because the temperature was dropping to -35 degrees and now I have over 167,000kms (103000+miles) I change oil at 200hrs regardless of milage and I have never added between changes.I have a Amsoil bypass filter and I do use oil anaylisis and I have never had bad readings exept the first oil change ( high Silicon) .
Jim O

 

How do you keep track of the amount of hours you've driven the truck?

 

2003s and up have an hour meter. With the engine not running and the key in the run position push in the reset button for the speedometer and hold it until the hours are shown .( It is in the operators guide).
Jim O

 

i run mobil one syn in mine and dad's trucks. we change it once every year at the same time and thats it. no problems...

 

How many hours or miles would you make in a year.
Jim O