Differences between the F350 and F450

[Tim_T]

I’ll post this in the truck camper discussion forum since that’s my focus right now, but maybe it belongs in the tow vehicles forum.

Yesterday I brought home a 2025 F350 DRW with the 7.3L gas engine to replace a 2023 F450. This post describes differences between my new F350 and the F450 I previously had. Again, this is comparing MY new truck and MY old truck. This is not an exhaustive list. It is the stuff I have found that might affect our future with a truck camper and a 5th wheel.

Jump to the table below or read on.

My F350 and F450 are optioned similarly – Crew cab, 8’ bed, 4x4, dual rear wheel, Lariat Ultimate,14k GVWR, soft tonneau cover, spray in bed liner, 5th wheel hitch prep, 250 amp alternator. The F350 was ordered with the camper package. The F450 was not, because at that time we were towing our 5th wheel and had not yet considered a truck camper.

Articles and videos all over the internet will tell you about the wide track front suspension on the F450 (resulting in much improved turning radius, bigger brake disks, bigger wheels and commercial tires, 4.3 axle, and the reduced payload on the F450. The greater towing capacity of the F450. Since that is covered so well elsewhere, I’ll discuss other aspects.

My comments on the material on the table:
Payload… A little math based on payload numbers in the Ford body builders layout book implies that the 6.7L engine and all the stuff associated with it weighs about 700 pounds more than the 7.3L engine and associated stuff. An F450 is about 500 pounds heavier than the equivalent diesel DRW F350. Dropping from an F450 to a gas F350 bought me about 1200 pounds of payload.

I believe the Ford payload rating is GVWR – truck weight, where the truck weight includes a full fuel tank + 150 pound driver. They probably assume full DEF for a diesel. Doing the math on my F350 CAT scale numbers, that’s 14000 GVWR – 7860 scaled weight = 6140. Considering that with my winter clothes, I’m about 190 pounds, that would match up to a rated payload of 6180. That’s close enough to the 6193 shown on the payload sticker on my truck considering that the cat scale reports in 20 pound increments.


The rear GAWR is the same for F350 and F450. But the F350 rear end weighs less, leaving 6340 pounds between scale weight and GAWR vs 5860 for my F450

The F450 Front GAWR is 400 pounds higher than the axle I received on the F350 with the options I chose (camper package, gas engine). However, the front end of my F350 weighs about 900 pounds less than my F450 front end.


Springs- The rear spring code on the sticker on the doorframe is the same for my F350 as the F450. I believe that means the same spring. They look the same as the old ones. The front spring code is different between my F350 and the F450. I assume that is a softer spring for the lower GAWR.


Sway bars- the F450 sway bars are much larger than the ones on the F350. I may have an aftermarket sway bar or two in my future.
Hitch receiver- While not as common as 2”, ball mounts for a 2.5” are more common than 3”.

Towing capacities – The 6.7L truck tows a lot more than the gas truck. Diesel F350’s tow a little less than Diesel F450’s. The 27500 GCWR of my new truck is plenty to pull my 22000 combined weight with our 5th wheel or the 13000-13500 pounds I expect with the loaded slide in truck camper.

We switched to the F350 because the truck camper we are getting would have put us well over GVWR on the F450 once we packed it for travel. For me, exceeding GVWR is not negotiable. Others will point out that the F450 is a stronger truck derated for insurance and registration reasons and can handle more.

We will pick up the camper Monday and put the truck to the test driving 400 miles home from the dealership.

[Dave Pelletier]

Good post and you seem to have a great handle on all the differences. Interestingly enough, my 2022 diesel F350 DRW (XLT Premium, 4x4, bedliner, 5th wheel prep, camper package) has a stickered payload of 5,453 lbs or 727 lbs less than your gas truck which aligns with your 700-ish lbs difference between gas and diesel though your truck sounds like it has a few more options.

As you point out, the F450's mandated 14,000 lbs GVWR is what causes it's comparatively low payload and it's a stouter truck than an F350 DRW. I went with the F350 DRW over the F450 because the 350 was already more capable than I needed for my purposes and I preferred the 17" LT tires/better ride and the 3.55 gears vs. the 4.30's.

I think the F350 DRW gasser is a great choice for a slide in truck camper as the 7.3 has all the power you need for that kind of load and you have more payload vs. the diesel. I have a 2023 F350 7.3 as well. A large 5th wheel may have you wishing for your diesel but should be fine with a 14,000 -ish lb 5er which is what it sounds like you have.

So, what truck camper are you getting?

Dave

[Tim_T]

We purchased a Host cascade. The photo is the morning after driving home to Michigan from the dealer in Sheboygan WI.

We visited the Cat scale before and after picking up the camper, and the weight is 4420lbs including propane and a gallon or two of pink antifreeze.
That leaves me about 1500 pounds for water, clothing, dishes, food, dogs, folding chairs, etc.

[Dave Pelletier]

sounds good; nice rig

dave

[Taildragger]

I wonder what is your experience with the 7.3L Godzilla engine. There is some controversy related to MPG's using 87 octane regular fuel vs 91/93 octane premium fuel with that engine

FORD fine print states the 7.3L Max. 430 horsepower and 485 lb.-ft. of torque based on PREMIUM fuel. All this time I assumed the 430 HP 7.3L HP/torque ratings were with regular 87 octane. Wonder how much is given up using 87 LL

The question is……will using regular 87 LL save you more than any noticeable difference paying for premium?

[Stircrazy1]

Originally Posted by Taildragger

I wonder what is your experience with the 7.3L Godzilla engine. There is some controversy related to MPG's using 87 octane regular fuel vs 91/93 octane premium fuel with that engine

FORD fine print states the 7.3L Max. 430 horsepower and 485 lb.-ft. of torque based on PREMIUM fuel. All this time I assumed the 430 HP 7.3L HP/torque ratings were with regular 87 octane. Wonder how much is given up using 87 LL

The question is……will using regular 87 LL save you more than any noticeable difference paying for premium?

the problem is unless your getting the revs up most of the time premium fuel won't make much of a difference aside from costing you more. so if your not running 5500rpm towing up a constant hill or only using part throttle you will never get to those conditions.

the best way to see is to do a big trip loaded up where you use a couple tanks of gas. then while empty tun a couple tanks of premium to get it all premium in the fuel tank then do that same trip again driving the same way with premium fuel.

I did this with my little turbo car where premium will make even more difference and for my driving style going to work and back (120mile round trip over 8 days) premium didn't benefit me at all.

[Tim_T]

Taildragger,
My History with the 7.3L:
I had a 2020 F350 SRW CCLB 4x4 with the 7.3L engine. I replaced it with the 2023 F450. And have now replaced again with the 2025 DRW F350. All 3 trucks were optioned as close to identical as I could.

The SRW gasser ran about 8-9mpg pulling our 5th wheel, 13ish locally unloaded, and 15ish unloaded on the highway. It was a great all-around truck and a pleasant if uneconomical daily driver. I switched to the DRW for more payload, diesel for range per tank and no high rpm, F450 for turning radius.

The F450 diesel did about 10 towing the 5th wheel, 16ish unloaded on the highway unloaded. This truck was used little other than trips with the trailer.

The new F350 dually is too new to have reliable numbers. I got about 8.5-9 mpg bringing the camper home Monday night, but that was 3 degrees F, windy, and we got stuck in traffic in Chicago. None of those is good for fuel economy. I expect this truck will primarily live in the garage when not hooked to the camper or trailer.


Premium vs regular fuel performance?
In general, you will get higher hp and torque numbers with premium fuel. If the computer detects knock (much less than you would hear) it reduces spark advance. Premium fuel means less knock, and slightly higher performance.

If I was spending a lot of time at 4000-5500 RPM trying to squeeze those last few horses out of the engine, I might consider the expensive gas. This isn’t a dragster.

I drive about 64mph towing or hauling. On the flats I’m in 8th, 9th, or 10th gear (1500-2000 rpm). Maybe premium fuel would allow the engine to make a few more ftlb of torque and stay in 10th gear a little more and might squeeze another tenth or two of MPG. I doubt that fuel economy difference would pay for premium. Premium might help pulling a mountain, or back off the throttle and take your time.

Purchasing the new truck was a compromise. We switched to the gas truck because we needed more payload in a truck that can haul the slide-in and can tow our trailer. I prefer towing with the diesel, but it is too heavy to allow us to carry our camper within GVWR.