I had my first towing experience in my 06 6.0 and i have to say I was quite impressed... but depressed I didn't get any better MPGs than I did.

So here are the stats...
310 mile trip from Del Rio to Port Aransas
- first tank was ~98% towing, but a lot of idle time and I averaged 7.78 MPGs
- I filled up after just under 200 miles and arrived in Port A, then drove around burning up the remainder of the tank - that tank averaged 9.8 MPGs
- Filled up on the return trip and got 9.1 MPGs on the first tank
- I'm still finishing off the second tank

For the trip down I was really pushing the petal and running ~72 mph, then we hit major rain and I slowed down, but that was just be before refiilling. In the return trip, we were in the rain all of the first tank and I was lucky if I got to run the posted speed limit (mostly 70) - if I had to guess the avg speed didn't go over 65 at top end. So I believe that is the big difference in MPGs.

Overall, I'm happy with the 6.0 and honestly, it's not that different in pulling than my V10 was... it just does it in a lower RPM range.

Monitoring the temps - with an ambient temp of 96* my coolant hung around 216*, EOT was 232* (or about 16* > than coolant) and the tranny stayed around 187*. On the return, the ambient temp was a lot cooler with the rain, but the overall temps stayed within 10-15* of what they were from the first trip.

I did have one concern - there were times that it sounded like the clutch fan locked... you know, that hi-RPM surg sound. But when it happened, I wasn't really running that hi of RPMs.

Oh - I also like the built in break controller. I have a Prodigy that I pulled from my old X and was waiting to try the built in one and it seems fine, so now I'm trying to deiced if I should keep the Prodigy or just stay with the in-dash.

 

OK, thanks for the report. That kind of thing is useful info.

BTW, what V-10 did you have, and what kind of mileage did you get on a similar trip?

 

1. Someone here --- what is the "good" EOT/ECT spread?

Is 16 degrees a bit high?


2. Sound

Probably just the fan coming on --- it makes a huge racket.

 

I agree, that fan is just doing it's job. Kicking in as required.

 

With my 06 6.0 I get between 10 and 12 MPG towing my 5 th wheel. I don't run as fast as you. I keep it around 60 maybe 65 tops. I've on occasion seen it as low a 8 mpg when pulling a lot of hills and windy conditions.

 

Pretty sure they're supposed to be within 5 degrees of each other...but that maybe just running light. 16 seems a little high, but Cheezit would be the guy to ask...he's got more experience with the 6.0L than anyone else I know. I know I'm going to have to bite the bullet and take care of my oil cooler. Apparently my coolant filter at 60k was too late to help mine...

 

Here's the unloaded temp readings thread:
https://www.ford-trucks.com/forums/9...-pressure.html

ECT/EOT split of 15* unloaded on the highway is what I've learned as the generally accepted point where you start worrying about rebuilding the oil cooler.

 

I had 2001 Excursion with the V10 - typically got 7-9 MPGs towing and 12-16 empty. So far with the 6.0 I've seen 19 on the highway.

OK - so being new to the PSD, tell me about the EO cooler?

I already have plans to do the rear end - paint is all but gone and I may have to replace the rear diff cover... doesn't look like it's leaking, so I may get by with just a fluid change and repaint.

I really need to read up on the maintenance for the PSD - but I've been so busy at work that by the time I get home, getting online is the last thing on my mind.

 

I would be happy with that mileage. I get worse then that but I do push it and am going over the mountains. 15 degrees is usually the difference your trying to stay away from.

 

Is the trailer you were pulling the 31G that's in your sig?
JL

 

Yep - that's the one...

 

So what do I need to do?

 

Ok, so that's a 8800lb GVWR at least from what I can find, and right at 32 feet.
What you're seeing here is exactly what I've been telling everybody about towing an RV.
Wind drag will kill economy no matter what you tow with. You basically saw the same fuel economy towing with the 6.0L as you did with your old 6.8L. This also backs up my beliefs that many of the diesel owners are inept at using a calculator, or just simply like to outright lie about their towing fuel economy. Your experience here mirrors exactly what I've seen on many occasions.
JL

 

Yeah - thats what I thought. I heard all of the PSD MPG hype for years and knew it was too goo to be true... that is the 'I get 15 MPG towing my 10K (insert trailer type here)". Empty mileage, hands down the PSD gets better than my V10 did - towing, slightly better, but not much difference.

As far as drag... absolutely - a HUGE factor. And that can plainly be seen by slowing down just 5-7 mph. I think for my next travel trailer, I'll look at a V nose... but it probably won't make that big of a difference.

 

Standing water on the roads and high speeds will have an adverse affect on mileage. Water affects mileage due to drag, as low air pressure in tires also will. Speed kills mileage too with wind drag, as well as being unsafe for tires, especially for your trailer tires. Trailer rated tires are usually only rated for <65mph and really should not be operated at higher speeds or you risk consequential tire failure.

With my 05 6.0 I get 10-11 mpg, hand calculated, when towing my 33' fifth wheel @ 11,500 - 12000 lbs. That is usually in mountainous terrain so I would imagine I could get better if I was traveling through the plain states etc., but probably not too much different if at all. I keep my air pressure up to the placarded tire pressure on both trailer and truck for both safety as well as economy.

I agree, Ford's tow command w/ tow haul mode is an awesome tow system. Great transmission and braking system.