New Noise Towing (First tow) and 9.5 mpg

[Snead Hearn]

So, I have this great new (to me) 2005 PSD. I towed my trailer a few days ago locally to test the set-up of the WD hitch and was blown away by the power and security of towing with the F250 over my previous vehicle. Anyhow,today, we towed 480 miles, including 2 passes. On the first pass, once we got to the passing lane, I let the folks behind me pass, then pulled out to pass a slow truck in front of me. I had been at 35, and it shifted down and pulled hard. Then, a new noise (not tire, not diesel, not turbo) started. It was almost like an extra fan noise from the engine area. I got in front of the slow truck and eased up and that sound slowed then stopped. From then on, it seemed like I had less power, and whenever I went up a hill (even a small one on an interstate) the overlaid sound came up for a bit. Even worse, I really felt like I don't have the power I felt test towing (30 miles) earlier in the week.

Is this normal? How about my MPG? I hoped this would beat my 5.4 gasser by a long shot. While I do have better comfort, I still go 62 mph.

I tow a toy hauler, so it has a pretty big flat spot but it weighs (loaded, I checked at a weigh station) 7900 lbs.

What is wrong? Is this normal? Am I in trouble?

80K on the truck. No tuner, no mods. Approx 34" tires.

Thanks for the help!

[fallendown]

Normal, the sound is the HUGE fan kicking on. Tow tunes are great, they keep you from having to downshift as much, and CAN lower your EGT's, (exhaust gas temperature) .

The mileage isn't bad with a toy hauler. Your toybox is a bumper pull? Mine is too, and it is harder to pull than a 5th wheel, the wind never stops dragging over the top. You would think that big wedge would help, but it would actually work better if it was backwards. ( like an airplane wing )

[roadrunner]

biggest mistake everyone makes when calculating mpg towing is weight, not wind resistance. our trucks are aerodynamically challenged to say the least, then add some form of a barn door off of the hitch and tow it sideways at highway speeds and you have really bad mpg. i had a flat front bumper-pull 24' enclosed trailer for several years, really hard to pull, i have since bought a aerodynamic front trailer and mpg went up to 15.5 @ best, where before the best i could do was 10mpg.
like above noise is cooling fan, i doubt other than placebo effect you have any reduced power unless you have other issues like a boost tube connector loose

[rdr99]

It is most likely your fan coming on. What were the ambient temps? Was a/c on? If you had a intake piping boot off, there would be a huge whistling sound.

[Manatee]

I don't think your mileage is out of line. I have never gotten better than 11 towing our 7500 pound RV.

Gosh, but does it tow well

[swilson143]

Sounds like you heard the engine fan. The fan is actually computer controlled and has several different settings. Screams like a banshee sometimes. I'm hoping you didn't have a powerloss and were just nervous after hearing the weird fan noise. If you're sure about the powerloss, get it to the dealer and see what they can find.

On a recent towing trip I saw my engine temp spike and had boost up at 36-37 psi... brought it in on the warranty and came away with a new turbo and engine cooler. On a 1000 mi trip last week, loaded heavier than ever before, the truck ran perfect. No temp issues and no boost over 28 psi.

My toy hauler weighs 11k-12.5k depending on what's in it. My mileage is typically 9-11 mpg. I have mods though.

Are you planning on any mods? Bare minimum get yourself an EGT gauge so you can keep an eye on exhaust temps. I'm really happy I did the exhaust and SCT tuner... really REALLY improves performance and if you drive gently you'll see some great MPG improvement too. I use the tow tune when loaded and otherwise use the street tune... but I'm pretty good about keeping my foot out of the fun zone.

Where are the pics of the new truck??

[chuckles]

fan is normal. I second the SCT tuning, and get a Edge Insight W/EGT Probe. They are really easy to install, and can monitor EGT, Engine temp, oil temp, coolant temp, trans temp, load, transmission specs. Intake temp, RPM, Injector PW.....etc, etc. and they only take up a small space on the left hand A pillar.

[StarDriver]

Originally Posted by Snead Hearn

So, I have this great new (to me) 2005 PSD. I towed my trailer a few days ago locally to test the set-up of the WD hitch and was blown away by the power and security of towing with the F250 over my previous vehicle. Anyhow,today, we towed 480 miles, including 2 passes. On the first pass, once we got to the passing lane, I let the folks behind me pass, then pulled out to pass a slow truck in front of me. I had been at 35, and it shifted down and pulled hard. Then, a new noise (not tire, not diesel, not turbo) started. It was almost like an extra fan noise from the engine area. I got in front of the slow truck and eased up and that sound slowed then stopped. From then on, it seemed like I had less power, and whenever I went up a hill (even a small one on an interstate) the overlaid sound came up for a bit. Even worse, I really felt like I don't have the power I felt test towing (30 miles) earlier in the week.

Is this normal? How about my MPG? I hoped this would beat my 5.4 gasser by a long shot. While I do have better comfort, I still go 62 mph.

I tow a toy hauler, so it has a pretty big flat spot but it weighs (loaded, I checked at a weigh station) 7900 lbs.

What is wrong? Is this normal? Am I in trouble?

80K on the truck. No tuner, no mods. Approx 34" tires.

Thanks for the help!

Your milage is in line with what it should be, your tall tires may hurt it a little. These 6.0s don't pull good till 2000 rpms. I've put 60,000 miles on my truck this year, about 58,000 with a trailer behind it, so I've learned alot about how these trucks work.

[Snead Hearn]

Thanks for your help. I think the powerloss was just in my head. The sound of the fan is a bit of a surprise, the way it comes on slowly and rolls off slowly. The thing gets good MPG on the highway (about 16 - 17!) and I wish I got better MPG towing, but really, I don't care, since it really does tow like a MONSTER! Love the towing.

Thanks.

Pix coming! I am out of town. Love the truck. I am concerned that my wife might steal it when we get home!

[chuckles]

They really are nice trucks. Get some good tunes, get rid of the EGR system, stud it (if it's in your budget), good exhaust, Coolant bypass kit, and good maintenance, and you'll be in good shape!!