This report is with 15-40WT . This first one in the other column was factory oil 10-30.


15-40 is better for me and it shows.

 

I am assuming all full synthetic?

Once again thanks for posting!

 

I pulled my 17K toyhauler through the mountains with an additional 1000 pounds in the bed (not counting the pin weight). I reached an oil temp of 240 three times and the fan came on full force each time and lowered the temp immediately.

 

No...factory oil is the dino and my oil that I run is the motorcraft dino oil as well.

 

I also run Motorcraft dino oil.

 

Scott - what oil were/are you using? Your long trip in some ways is similar to what we are doing though aren't doing the Rockies but the Wasach and Sangre de Cristos with a 77500 mile truck and 4500 miles so far on this trip since 17 August with another 3-4000 to go. I may send a sample of the Motorcraft 15W40 off to Blackstone for that late line in the sand on to be an 80K+ engine

 

Oooops - very slow 'net here in Cedar City, UT KOA. Question answered

 

Just the motorcraft 15-40Wt oil. Same oil I used in my 6.4 and it always held up good on the 5K oil change intervals I run.


I do think it would go the 3--4k more you have for your trip though.


Running my Monarch pass and on I 70 thru the eishhower tunnel and several other long grades is a heck of a workout. Especially when you have your foot thru the floor.

 

I will most likely do the oil change at the end of the trip. I did the totally useless look/smell/feel test this morning and it still looks good.

That Colorado portion of I-70 can be a challenge though I do believe that Utah has some l-o-o-o-g 6-7% grades that are about as bad. We were able to 'blow' past lesser RV combos with ease. The last time I did the CO portion pf the route was in a foreign made underpowered rent-a-clunk on a ski trip though I did run my ancient 460 F350 with a 30' fiver along the route as well many years back.

 

Rotella T6 5W40. Runs around town 198-203, highway speeds 203-210, with the camper normal driving 210-215, long grades with camper 230-245. This doesn't bother me a bit because when it runs up this high it goes back down to normal operating temps in a matter of just minutes, the cooling system is truly amazing. Not to mention no regens when running hard.

 

That is what I use.......

Reading the Diesel supplement book that came with the truck......for the cold winters and the hot summer pulling heavy (18K lbs) loads....the book lead me to use the 5W-40 synthetic. I'm sure, there is no one answer. my next choice would be the 15W-40 in the summer months and the 10W-30 in the winter......

 

That's what we run, lots of idle time in the winter. Always Motorcraft.

 

I'm with you Roy, the T6 5w40 fits all the conditions I run in and it's a little bit less expensive than the motorcraft. I tow 99% of my miles and change the oil when the truck tells me to. I think the 15-40 would be my next preference but honestly I don't see how it would really matter that much. I'm trying to get the best mpg I can and the lowest cost per mile I can, within reason.

I've never been able to get the oil above 242° I think, and I've tried.

 

The highest temp I have seen is 243 degrees.

 

Have any of you guys looked at the boost when the oil temp is that hot? Mine has a boost loss when under heavy load and the oil gets this hot. It falls to about 12 lbs of boost, and of course looses power when hot.

Thanks,
RSC