Just finished a 2200 mile round trip and thought I would post some observations and get some opinions/comparisons. I flushed my coolant 13 months ago per the powerstrokehelp.com instructions. The oil cooler and EGR cooler have 56k on them and I installed the coolant filter right after they were replaced. No coolant loss, puking, or any type of smoke under load and the truck now has 126k. The ambient temps for the trip were between 91 and 105 degrees. I'm pulling my 13,000+ pounds 5th wheel, 13 feet tall, which I assume places the truck in the "severe service" range. The speed is always around 63mph.

ECT--At regular cruising with some minor grades it runs around 210. At 210 the fan comes on at about 1400rpm and cools it to 204,then the fan returns to 400rpm. Then it slowly goes back to 210 and repeats. During about 3 climbs on long grades, it went up to about 215-219 and the fan kicked in to 2500 and brought the ECT back to 195 really fast. Then it went back to the normal 210/204 cycle. Its always consistent.

EOT--At regular cruising speed it runs around 230-232 which is 20 degrees above the ECT. When the fan comes on at ECT of 210, it cools down a few degrees, then returns to 230-232. On the 3 grades it went up once to 247 and once to 240, then cooled right down with the ECT when the fan kicked in to 2500.

TFT--Consistently runs around 165-168. On the longest grade it went up to 178 with the ambient temp at 105, but cooled back down to 165.

 

My truck and camper are similar. I recently ran up through the Smokey Mountains and heard fans kicking on that I had never heard before. They sounded like hydraulic pumps turning on or something. I even recorded, but am sure it is the same fsans that you are speaking of. As I would climb the grades, I would turn on the Torque App and watch the temps rise and fall. Glad to see its all working for both you and I.

 

I see mostly the same temps towing with my 05 Excursion....EXCEPT
My oil temps are usually no more than 10 - 12 deg higher then my water temps.

Maybe your oil cooler is getting fouled/clogged?

 

was thinking the same thing. Trailer is 8k and I see 10-12 on a 95 degree day up hills.

 

Oil temps do seem to be high. I tow a 12K 5vr and have not seen above 220, and even then, that was momentary. Another testament to having a set of guages / Scanguage / Edge what have you. If it were me I would be looking at a flush of the oil cooler, if there is a flush that will work, or putting some money aside to change the cooler out.

I think when you get to temps not too higher than that your looking at defueling and REALLy hot Oil system components.

 

Recently completed trip to NC mountains. I have similar results on ECT and TFT. My EOT, however, was much higher, running 240+ sometimes. I'm fairly certain my oil cooler is partially clogged and am saving for the repair. In the meantime, I back off the climb or turn off the A/C if I see EOTs get that high.

 

I was trying to remember how my EOT looked last year while I was towing in the heat but I can't recall. I don't think they were that high when I was towing on level ground. I'm keeping an eye on it to see if the EOT increases at all throughout the next few pulls. I hope I don't need another oil cooler.

 

the test is to run for 15-20 minutes on flat ground at operating temps unloaded and then check the split. If it's higher than 15.... they say you may have a cooler problem. They all say to flush using the VC-9 stuff before the cooler change out.

 

I have read a ton of these EOT threads and I have come to the conclusion that some of these run different temps then others. Just because one guy never sees temps higher than 220 no matter what the OAT is or what grade he is pulling doesn't mean squat. The 65mph flat land test of 15 deg or less is the only thing that holds water. Except for the guy that was seeing 270 EOT. That's no beuno.

 

We are in the lower part of the Smoky mountains here in NC, my EOT was running at the high point of 223 and average of 210, now my ECT was between 211 to 219 but on average it was about 8-10 difference. Oh yes my TFT was at the highest of 179 and back down around 167 when cruising along. It was 92 degrees when we got here.

 

Unloaded I'm ok. Mine runs within the 15 degree limit, but I'm always on the high side like 12 or 13. That hasn't changed since I got the gauges. I have always wondered if the rearend gear, weight of the truck, and the dual wheels play a role. Seems like a 350 with a 4.10 and dual wheels is working harder than a 250 with a higher gear at 65. If so, would that cause a little higher spread just like it does when towing? I wish I had gauges when I had the cooler replaced so I would have a benchmark. Then I would know if my EOT has been increasing over time or if it just is what it is. I know that when I went to Yellowstone 2 summers ago, I had the EOT alarm set at 235 and I exceeded it at least once while towing.

 

I think there may be quite a difference in our 5ers. Mine is almost 40 feet and probably weighs a ton or so more. That could be the difference.

 

Tracyclifton no doubt there is a big weight differentials mine empty is 5708 with max weight of 7900lbs. It is 31' long.

 

You also have a dually. It wouldn't be far fetched to expect a few degrees more EOT compared to a SRW.

Josh

 

Just for piece of mind I went and did a run to check the delta between EOT and ECT. After 20 minutes on a fairly flat run, just a few mild hills, 58mph. ECT 194/EOT 208. That's about normal for my truck. In town doing errands, ECT 195-198/EOT 204-208. I'm keeping a close eye on it. I don't want to be one of the guys who spends $2500 to change the oil cooler and gets the same readings afterward. So for now, I'll keep an eye on the gauges and see what happens.