I was towing the 5er (about 15000#), across Southern Mn and SD today going right into a 20-25 mph wind in upper 90 temps, saw 228 on the oil temp and 199 on the tranny temp. Wondering what some of you guys who tow see for warmest temps and at what point you start to get concerned...

 

Climbing 7% grades, I frequently see 242° and that may last for 10-20 minutes as I climb. Once over the summit it drops pretty quick back to the low 200s. Coming home from Jackson Hole pulling a load of horses Saturday it stayed at 208° most of the trip, and the outside temps were 53°

 

I asked this same question in another post about a month ago. I have seen engine oil temps in the neighborhood of 230 when pulling a 12,500 lb trailer up a 10 mile 6% grade. The temp dropped quickly once I crested the grade. I was also told that the fans come on at 240.

I watch my temps pretty religously and they usually run around 200+/- for engine oil on flat ground and around 190 for the trans temp. The engine water and trans temp guages on the dash don't seem to move at all once up to running temps. When pulling short steep grades it is common for me to see 215 on the engine oil temp.

Mike

 

Towing the toyhauler into the Adirondack's this summer in 95+ we hit the high 240's and over 200 on the trans. As stated above, dropped very quickly after cresting the hills.

 

I agree with you guys. My oil temps have reached almost 250 when towing or when I'm pushin pretty hard!! but I tell you, it cools down quickly too. Something my 6.0l never did. I had to stay off it, a lot, even goin down hill!, then..... Now, my trans runs just under 200. The oil, usually around the 200 mark. I think 200-235 towing would be considered normal. I've been told these engines are designed to run hotter. But are designed to cool down quicker and I have witnessed that! I'm finally impressed with Fords new engine.

 

You have two cooling systems on this engine. The Oil Cooler is located on the Primary Cooling system.

You have two Thermostats on this system. The 1st opens at 194°F and the 2nd Opens at 201°F

So if the cooling system is keeping up, your oil should be in the 201° range. It would be rare to see it below that temp.

So when we climb grades, the oil temp climbs as the oil does it job of helping to cool the engine. It will quickly drop down to the temp of the coolant as soon as we stop producing excess heat.


The flash point on most oils is well into the 400° range, so temps in the 200-250° are with in working ranges.

 

Good info PH. I like to follow your posts about the cooling systems.

I routinely see 242 degree oil temps pulling my toyhauler up the mountains here in WY and SD. The last time I weighed my truck and 5er, we were just a tick under 30K. Two weeks ago me and ma headed up into the Big Horn Mtns (6-7% grades), and we were loaded up to boondock for 8-10 days. Extra fuel, water, long term supplies. I am always happy with the performance of my dually dragging that anchor up the hill at 55mph. At 242 degrees, the aux fans come on and quickly cool things back down. If I keep my foot in the pump, the fans stay on and decrease and increase speed and intensity as needed to stay cool. Tranny temps usually hang around that 199-203 range under same towing condition.
When we were coming off the mountain, there was an older model Chevy dually gasser pulling an older model 5er up the hill and he had about 10 cars stacked up behind him and climbing at about 15 mph. I would like to know what his coolant temps were running. I think FOMOCO did a good job with the cooling system, except for the problem child leaking radiators.

 

I have been on the road towing for the last four weeks in temps up to 98 degrees pulling 8% grades through Montana, Utah and South Dakota. Regularly pushing 234 to 238 on the grades with 12,500 lbs behind her. Hit 244 a couple of times and as others have said it quickly dropped down after reaching the crest. I monitor my oil temp on my MiniMaxx so it is easy to keep track of it. Never broke 200 on the tranny once. Never dropped below 60 mph.

 

I see those numbers all the time, 36' 5th wheel at 17K +

 

Yep, see these temps all the time towing and a few times hit 245* on a 100* day climbing 6-8% grades but chills right back down after cresting the top.

 

I to see the temps mentioned above on a daily basis, I am sure that the computer will shut you down if temps get to high, I have not experienced this in these trucks but have in semi's.