2018 F150 lariat Screw w 3.5 EB w/ standard tow package. I will be towing my 6000 lb camper soon and wondering what normal engine / trans temps should be. I just had a coolant flush and thermostat replacement. I turned on the digital temp.values with forscan and see 200-217 F engine temp without towing. That seems normal. Wondering what would be normal when towing or more importantly, what would be abnormal.

Before the flush/thermostat, I saw 230 once not towing at 70 mph / 65 F. That seems high for not towing.

With the digital gauge enabled, I can see it's clearly not true water temp. It changes way too fast for water temp. I read somewhere that it's head temp adjusted to look like water temp. That's why I'm asking.wjats normal for this fake water temp.

 

My 2014 transmission is 195-205 range every time I check it when not towing. I don't pull over 4500 lbs, but will often see 215 when towing. The most I've ever seen was 228 when pulling over a pass in Colorado last July. I can't see actual engine temps.

I'll be honest, I was a little concerned with that, but the temp gauge was still on the cool side of normal even at 228. I asked the guys at the local transmission shop what was normal and was advised that it varied by manufacturer. With some vehicles they would be worried at 230 degrees. But according to them they wouldn't be concerned with anything under 250 on my Ford.

I have the 5.0 V8. But based entirely on what I've observed and read here the EB engines can sometimes get a little hotter. Part of it is a lot more power from a smaller engine that makes it harder to dissipate the heat. Part of it is that the EB engines develop more torque at lower rpm. The trucks want to run in higher gears which means slower engine speeds. The trucks will pull in the higher gears, but manually downshifting by locking out gears and getting rpm's up help cool the engines when towing..

 

Hi

I just completed a tow of trailer weighing ~6300 through Nevada and California with 2019 and 3.5 turbo. I experimented on some of the long hills and confirmed that staying off the turbo and just using gear lock-outs to run at higher rpms did keep temps below 220 on both radiator and tranny. Typically 214 on the coolant and 207 on the tranny.

Outside temps varied all over from 50 at high elevations to 90 at lower.

If on the Turbo I saw coolant hit 230, but tranny was only 207. When temp hit 230 I down shifted such that revs were at about 3200-3500 and no or very little turbo

my GCW was 12300

 

Depends on a lot of things including the ambient temperatures and where you tow. You can overheat these trucks here in Utah because you could be towing in 90+F temperatures at 6000+'. That combination of temperatures and altitude is very demanding on the cooling system. My 2014 has seen 240F+ coolant temps more times than I can count but the 2014's also had a pathetically small radiator. Now with a Mishimoto radiator upgrade I haven't seen it break 230F but it will hit the 220's no problem. This last weekend I was pulling a grade on a 78F day and hit 225F spinning 3700 rpm.

Higher RPM's help as they keep the water pump moving faster and reduce the boost a bit.

 

Lots and lots of threads discussing "high temp" conditions when not using OEM stat.
If you don't have an OEM stat you may experience higher than usual temps.

 

Just to close the loop on my question. I towed my 6500 lb trailer over 100 miles. In tow haul mode, the rpms stayed above 2k and the temp was around 220. The digital gauge is nowhere near a normal water temp gauge, saw as high as 228 briefly and then was down to 208 10 seconds later when I created the hill. I had one 3 miles long hill and shifted down until the rpms stayed above 3k dropped the temp to 212. Trans temp was right around 208 the whole time.

I'm happy with these temps as modern engines tend to run hot but the transmission and engine computers kept the towing temps only 5-10 degrees above non towing temps.

 

I live at 6k ft and tow a 4k lb TT over mountain passes. While not towing my digital trans temp runs between 195 - 205. Towing my trailer on the flats during warm weather my trans temp runs between 200 - 215. On long inclines it'll run in the 220's. I remember hitting 237 once in New Mexico. This is with a 5.0 and tow package trans cooler.

 

When Towing a trailer behind, The engine temperature should not change a lot. yeah a degree or two would be perfectly fine, but if it is a little more than that, You should be worried about it. Also make sure the temperature of your coolant remains lower than 110C or 230F.

 

Hmm the above sounds like a rule thumb from yesteryear. With turbos kicking in and things heating up under the hood, and other factors, coolant temperature will fluctuate more than a few degrees.

 

May not be good, but it's normal for my 2017 3.5 Lariat Max Tow with 5 Star 91 octane tow tune... Pulling a 6,500 LBS. travel trailer up 6-7% grades in 90* plus temps at 2,000' - 3,500' above sea level it's not uncommon for my truck to hit the 250* de-rate. Most of the time I can keep it just out of de-rate by locking out gears 6-10 and letting her rev, but that still results in temps between 240* and 246*. This is pulling those hills at 60-65MPH.