Can anyone explain to me why I have never seen an F-450 or F-650 with out a dually rear axle, but I have seen a few F-550 with four? I've only seen this in tradition pick-up style chassis (never a utility body). I'm aware the additional tires is to increase the payload capacity over the axle, I fin it odd that I've never seen a 450 with less than 4 tires on the rear axle when I've seen 550s with only two.

450 550 650 ect come with a DRW axle from ford

Because of what they are rated to tow at if it was a SRW there tow rating would be less

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95 Ranger XLT 4x2 2.3 I4 5 speed 206,000 *dead*
96 Ranger XLT 4x4 4.0 V6 5 speed 173,000 *alive*
D35 front, 8.8 rear, 3.73 gears, limited slip rear diff

I understand all of that.

Are you telling me the 550s I saw with SRW axles were an axle swap done by the vehicle owner and did not come that way stock?

proly wasn't a real f550
cuz yes 550s do not come from ford with a SRW option

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95 Ranger XLT 4x2 2.3 I4 5 speed 206,000 *dead*
96 Ranger XLT 4x4 4.0 V6 5 speed 173,000 *alive*
D35 front, 8.8 rear, 3.73 gears, limited slip rear diff

It's called a super single. One big rim/tire to replace two. The single claims better mpg and some other minor advantages, but on a f450, 550, 650 I'll bet the change was just for looks.

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Why does everyone think prerunners just jump stuff?

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