GreggGDMomentum

The ford site shows rear axle capacities are lower on the F450 by 400 lbs (makes no sense) https://www.ford.com/commercial-truc...odels/f450-xl/

They also now rate the F450 at 40,000 GVW on the regular cab 4x2 (High output diesel). "5th Wheel / Gooseneck Towing - Maximum available Loaded Trailer Weight Ratings" This sounds like you say Trailer weight so 8K pin load at 20% (5er or GN). Where the F450 only shows a rear axle capacity of 9,900 lbs for the F450 and 10,300 for the F350.

The specifications sound a bit fishy to me. WHY, https://www.badgertruck.com/heavy-tr...lassification/ states class 3 trucks GVWR 14,000 lbs. 5,300 lb front axle (2wd) on a F350 and 10,300 lbs on the rear actually puts it in the class 4 category (14,001 to 16,000 lbs) if you axle it out and almost into the class 5 with the 4wd front axle giving it a GVWR of 15,900 lbs. Note the F450 is axled out at 15,500 lbs.

Marketing at its best. Either way, once you exceed the 26,000 lbs total load you really should be carrying a CDL in some states (some offer a higher normal class license for personal use over 26k).

Everything with Ford and marketing and towing capacities is a rabbit hole, welcome! 🤪 I heard also that the cab only model commercial version F450 it's a different frame like the 550 and can carry more weight. Probably just a way for Ford to hit a niche market for their F450 with a bed, possibly that particular customer have CDL's...
Another note, prior to the shortage of Super Duties the F450 was about the same price as a similar trim version as the F350 dually. Don't look at what the dealer is asking for them, look at the original MSRP sticker.

BTBRV out of Chorpus drove to Houston to look at a Chevy 4500 and the guy would not sell it to him based on the intended use of towing. He already had a F450 and was looking for another class 4 for comparison. He did a good video on the GM Class4 (up to Class 6) video with the salesman that he was talking to. Since GM is using the Freightliner chassis and cabs, the 4500, 500, and 6500 are all the same frame and cab, just different axles under them to get the class. Ford does not change the frame until the 550 class.

As for the cab only 450, I know several people who have purchased the C&C but added the bed later. MOST NOT ALL C&C have a different frame width but still same profile (GM and I think Dodge are parallel behind the cab on C&C vs tapered on the ones with a box bed). F550 is straight rail IIRC vs the F450 being offset (bed steps up from cab).

GM 4500 frame note bottom profile only changes top profile is FLAT:
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This is what I find on the F350 and F450 frame: Note the Z (double drop) in the frame.
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