Let's get something out of the way first.

OUR 2018 6.7 DIESEL TOWED THE SAME 5TH WHEEL FASTER, LESS EFFORT, AND BETTER MILEAGE.

Our truck is a F350 Tremor with 7.3, 4.30 gears, and 35” tires. Tow Haul mode was used for the complete trip. I Cat scaled our truck about a month ago, the trucks weight was 7220, truck and trailer was 18,460. I believe we were about 500 lbs. ~ heavier packed for our trip. 5th wheel is a 2020 Grand Design Reflection 303RLS.

Our tow was from Disneyland area to Las Vegas and back.

The trip includes a few climbs with up to a 6% grade. I could maintain 65+ on any grade coming or going. The gears used on our trip were 5th thru 10th. When I was in 5th RPMs were right at 4000 @ 65mph.

At one point two semis were side by side going 40 up a long grade, after the semi finally over took the other semi and merged back to the right lane I floored the gas pedal and I was up to 65 in no time. I've never towed with a gas engine that pulled like the 7.3/10 speed. RPMs spread was about 350 between gears so it was like the truck was in the correct gear most of the time. When I wanted to force a downshift I just gave a little more throttle and the transmission shifted down a gear. Transmission temperature ranged from 208 - 228.

I wasn't worried about gas mileage on our trip. Gas mileage was 8.8 for our trip. Seems like we were always going up and down both ways, never really any long flat runs. I did watch the instant gas mileage display when the road was fairly level and saw 10-11 MPG at 65.

I believe the 35” tires didn’t help in any way towing, if anything it hurt performance and mileage. Standard 33” AT tires most likely would have towed better and returned better mileage.

 

how does the around town mileage compare, my 2018 6.7 is like 14...
so it sounds like the diesel is better but the 7.3 was no big annoyance while towing?

 

Nice report. Thanks

 

yes great real world review ... sounds like a great trip to take...

 

I'm probably a bad example for city mileage, living on the Los Angeles/Orange County boarder. Traffic lights every 1/3 of mile, if you don't catch them just right you get to stop at everyone. Commute is 6 miles to work.
My city average is 10.8 - 11 so far.
I believe the 7.3 does exactly what Ford describe it would be, fill the gap between 6.2 and the diesel. YouTube and this forum helped me make my decision.

 

Do you tow at 65mph or was that where the truck was comfortable? I know some of that is Cali so 55mph limit.....
We usually tow our 5th wheel at 75mph, and yes my tires are rated for it....the 6.7L is very happy there. my 6.0 diesel was not happy over about 68mph, and it really liked 63mph.
Just wondering, thanks!

 

I'm normally between 62 and 65, truck was happy from 62 on, and able to hold 10th gear. Any slight incline and the truck would drop down to 9th. I think the taller tires had a lot to do with that, my gear ratio with the 35" tires works out to 4.09~.

 

Looks like you got the truck that fits your needs and handles it well. I see no evidence that a buyer has compromised by buying a gas 6.2 or 7.3 when reading comments on this forum. Happy Travels!

 

Thank you for taking the time to post this review! Good info.

 

Nice report. I like the numbers and your comment on the semis at 40 is my only complaint on the 6.2. It takes a bit to build the speed up and the jump from 2 to 3rd is a little to big in that situation.

For a little comparison, we did a 500 mile trip with our new GD Reflection 337 to Gold Beach on the Oregon coast from McMinnville. Did a big loop with some freeway and lots varied terrain. MPG was 7.8. We were lightly loaded at around 20,500lbs combined. On Hwy101 I found if was better to lock out 6th. 4.30's and stock tires. I kinda have the bug to upgrade but current truck is almost paid for....

 

Thanks for posting. I just took a test drive with my new 7.3L F350 w/ 4.30s attached to our Grand Design 28BH. I was very pleased with the performance compared to my old 2011 6.2L F350 w/ 4.30s. I’m looking forward to our first big road trip. Good luck with your new truck, it looks great.

 

This past weekend I just towed for the fist and last time with my 2017 f350 6.2l. I traded in my 17 for a brand new 19 diesel. I also have the 337 and going up a 6% grade as I was cresting the hill it downshifted into first gear. After it crested that hill at 15 mph it started making funny noises. Not playing around anymore. Now I cant tow my trailer till I get 1000 miles on the new one. I took the 2020 337 to Lake Chelan state park in Washington state.

 

Wrong thread...damn mobile

 

Now I am getting more interested in upgrading my F350 2017 6.2 w/ 4.30 to a 2020 7.3 w/ 4.30 and 10 speed. We tow a GD 337RLS about 20 times during the year and I use it as my daily driver, so I just couldn't justify going diesel. Will have to wait to see more stock her in the NE.

 

I love McMinnville, used to go up there every month for meetings...when I worked for Evergreen Intl Airlines. I'm sure the town is different now, with EIA going out of business.