Talked to my ford dealer today to get a price on oil. He says that their service guys only use 10w30 for the 6.0 PSD's. Even in the summer? it can get 100+ degrees f here in the summer.

Does this sound right to you?

 

I use only 5W-40 synthetic & 15W-40 with dino oil I have never talked to anyone useing 10W-30 but if its CI4-+ rated I cant imagine why it wouldent be ok! Blackhat?

 

It's a whole lot easier to find 15w40 than it is to find 10w30(has to be diesel specific)

 

i dont remember every seeing a 10w-30 diesel oil...?

 

Diesel suppliment doesnt recomend 10W-30 for towing. Could use it for getting groceries though. The HPOP on these love to shear the grade of oil down.

 

Well your dealer is living off of old news. Early in the 6.0's life with the problems of the C94 injectors (these were replaced in March of 03) FMC came out for a short time saying 10W-30 was the oil of choice. That was revised fairly quickly to go back to 15W-40 from 30F & Up (or towing) and only run 10W-30 when outside temps are 30F & below.

The newest recomendations are to run 15W-40 from 10F & Up and if towing to run 15W-40 from -20F & Up.

FMC says that 10W-30 can be used above 30F but it is not the oil of choice at higher tempratures or towing.
They go on to say that 5W-30 or 5W-40 can be used from 30F and below. Now i have never seen 5W-30 in diesel oil in the US so i do not know of its availability. The only 5W-40 diesel rated oil i have ever seen is all synthetic. Since 5W-40 is synthetic and the flash point is similar to 15W-40 dino i would see no problem running 5W-40 at all temperatures.

Personally i run 15W-40 dino year round, coast to coast and i tow alot. Living in the desert southwest 10W-30 is not in my vocabulary. The 6.0 is extremely hard on engine oil and quickly shears a 15W-40 down to a 30 weight oil, i don't like to think about where the 10W-30 is going to shear down to.

If you live in a cold climate and don't tow alot then run 10W-30 in the winter for easier starts (or just plug in sooner if you run 15W-40) and 15W-40 in the summer. Or you can run 5W-40 year round if you live were it gets really cold in the winter.

Here is the latest TSB on the subject
http://www.ford-trucks.com/tsb/fullt...hp?tsb=05-16-6

Hope this helps

 

If they put 10w30 in my truck they would be taking it out as soon as I knew it happen. I wish the dealers would look into an owners manual before they give advise like that. Would 10w30 hurt using it above 100+ degrees towing . I don't know for sure but I wouldn't take that chance . They prob recomend it because thats what they carry in bulk . If you did have a problem would they back it up ?