Have a question about using synthetic oil in a 6.0L. When I bought the truck back in 06, the service guys told me to only use 10w30, and that I should never use a synthetic oil.

 

I use 5w40 Amsoil full synthetic in my truck. Had no problems. Guys with a lot more experience will chime in.

 

Fuel injection pump? LOL!

Hopefully the service guys you spoke to aren't FORD service guys.

There is no fuel "injection pump".

 

Using the Shell Rotella 10w30 synthetic now and seems to allow for easier starts in the cold. I will probably switch back to 40 weight in the summer

 

Many folks use synthetic 5W40 and it works fine!

 

Yes, 5w-40 works great. I guess I was too busy chuckling about the "fuel injection pump" comment from his "service guys".

If I ever heard a comment like that come from the mouth of my service folks, I would never let them lay a hand on my Powerstroke.

 

Stay away from that place. 5w-40 won't give you any problems..

 

The most important thing you need to know about using 5w-40 is:

FORD MOTOR COMPANY HAS APPROVED AND BACK SPEC'D 5w-40 FOR ALL POWERSTROKE DIESELS. (That's FoMoCo, not the idiot service guy.) In fact, Ford sells Motorcraft 5w-40 synthetic diesel oil.

I've used nothing but 5w-40 in my 2005 Powerstroke since new. I've towed in Death Valley in August and use the truck year 'round in Northwest Wyoming.

Using a synthetic 5w-40 in a 6.0 is not about extended oil drain intervals. Lubrication nuts on Bob Is The Oil Guy . com argue that oil analysis show 5w-40 doesn't last longer in 6.0s than conventional oil.

For me, 5w-40 is about start up. A thinner oil gets moving around a cold engine quicker than a thicker oil. 5w-40 is essential for colder weather.

There are plenty of threads on engine block heaters and hard starting in cold weather. Virtually all of these posts are about cold weather starting with 15w-40 or 10w-40.

In five Cody, Wyoming winters that included dozens on 8 - 10 hour cold soaks at -20F or lower, I have NEVER used my block heater. I have personally witnessed how 6.0s in the same conditions start with an without block heaters with conventional oils - that would be painfully, slowly, barely and not. In fact, I've had more than one 6.0 owner ask me how I can get my truck to start so easily in winter. The guys who ask always use a 15w-40 year 'round.

You can safely use a 5w-40 all year without worries.

0w-40 is available in Canada and many 6.0 owners use in in colder areas.

 

You can safely use a 5w-40 all year without worries.
I agree and have been doing so for almost 90,0000 miles.

 

I use the 5W-40 to help with cold starts in Michigan and it works well. I've used Rotella and Premium Blue and my personal preference is the Premium Blue. It's a buck more than the Rotella syn but when your spending $100 an oil change what's another dollar per gallon?

 

i use 0w40 syn year round and works great

 

I've read and reread this thread and where did he say anything about a "Fuel Injection Pump"

 

The OP edited his post for some unknown reason so that anybody who didn't read the original would be confused.

 

I'm guessing the OP added the "injector pump" part and then edited it when he saw the posts laughing about it.

Either way: 5w40syn year round here.

 

I've had great results using 5W40 synthetic in 2 Ford PSD's (F250 & F350) for the past 8 years...
199,787 miles with the 6.0 Grin