Ok, so I'm considering a new King Ranch Super Duty (4x4, CC, SWB or LWB, 6.4 auto)... primarily for towing the 5'er which weighs in right around 11.5k loaded. The Ford towing supplement lists the same max 5'er weight figures for F-250's as it does for SRW F-350's (15,200lbs)... yet a trailer that heavy (with a 15-25% pin weight) would exceed what they list as the max cargo weight and GVWR of an F-250 by quite a bit.

Any idea what gives? (and yes, I'm aware that options, gear, people, etc., in the truck reduce the numbers even more)

Also, can somebody tell me what mechanical/equipment differences there are (if any) between a 250 and a 350 besides the rear leaf springs, given the same configuration -- (e.g., 4x4, CC, LWB, 6.4 auto)?

Thanks in advance for your comments!

 

The springs on the F-250 and the F-350 SRW are the same.

There are 2 differences (besides badging).

First, the F-250 has a 2 inch (nominal) lift block between the rear axle and the rear leaf springs. The F-350 SRW has 4 inch (nominal) blocks.

Second, the F-350 SRW uses a different rear axle shaft with a higher spline count. This is why the F-350 has a higher rating for cargo. Max trailer pulling weight, however, is the same.

While an F-250 can pull 15,200 you still have to watch your pin weight on the 5th wheel so as not to exceed your cargo weight.

 

Now is there a difference between an F250 SRW and a F250 SRW with the snow plow prep package in terms of coils in the front?

 

All depends on what other suspension options are chosen (if any).

 

Yes snow plow package is different springs up front, that is all.

 

I was looking at one of each sitting side by side today (brand new '08's, a 250 and a 350 SRW) and the rear springs werent the same... the 350 had an additional leaf. Is there some sort of option that add's one?

 

If its a leaf above the main pack, then its the overload spring. The ?snow plow prep package? will add one on a 250 or 350.

 

That extra spring on top of the leaf springs may be part of the "camper package" option.
I believe the snow plow prep option give the truck 2 up on the front springs and camper pkg is a 1 up on the rating

 

I thought F250's were 3/4 ton trucks and F350's were 1 tons. Maybe I'm wrong.

 

That's the generally accepted definition, but it really doesn't mean anything anymore. You can now get an F-150 outfitted to tow what used to be exclusive "1 ton truck" loads 30 years ago.

 

For 6 months I have been meaning to ask about the difference between F250 and F350 too. In my case it is because I was concerned about an F350 riding like a log wagon with no load in the bed or trailer hooked on.

Sounds like all things being equal I should not shy away from a suitably equipped F350 for fear of a rough ride when 95% of the time it is not towing or hauling anything, correct ?

What about changing the 4" lift block for the 2" ones to lower the rear of the truck so I don't have to worry about a cap not clearing the top of the garage door, is that tough to do or expensive ?

Thanks for the information, I'm really digging this forum !

 

In some cases, combined with a diesel, and other things that raise the front-axle load, you may wind up with a Dana Super 60 axle in front too...

 

From what i have been told (and seen) the 350's come with the helper springs. The 250's have to have certain equipment added in order to get the helper springs (camper pkg, severe service pkg, etc).

I also thought the spring ratings were different from 250 to 350. They may look the same but they have a higher rating. Somebody like FTE parts guy should be able to verify if it is the same or different part number to replace the springs. When I test drove trucks I noticed a difference in ride quality too which also makes me think there is a difference in spring rates.

I dont have the factual data, and I am not trying to argue the previous points made, but I have always been advised that the springs are different, not just the blocks. I understand the logic in heavier axles but I dont know how that relates to payload in the bed. If the only difference is the block then wouldnt they have the same payload? Just one truck would sit 2 inches higher than the other?

 

here is some info I found on the sales side from Ford, might help a little. if I get a little more time I'll look up the F350 and post that also.

Ed




CAMPER PACKAGE (471)
Availability:
• Optional on all F-250 Pickups
Not available with:
• 20" Wheels and Tires, Pickup Box Delete (66D), Stabilizer Package
(63B) or Heavy Service Suspension Package (67H)
Includes:
• Extra heavy service front springs 4x2 (2 Up upgrade above the spring
computer selected as a consequence of options chosen. Not incl. if
maximum springs have been computer selected as standard
equipment)
• Heavy service front springs (4x4) (1 Up upgrade above the spring
computer selected as a consequence of options chosen. Not incl. if
maximum springs have been computer selected as standard

HEAVY SERVICE PACKAGE FOR PICKUP BOX DELETE (63R)
Availability:
• Optional on XL and XLT
Not available with:
• 20" Wheels and Tires, Stabilizer Package (63B), Snow Plow Prep
Package (473) or Heavy Service Suspension Package (67H)
Requires:
• Pickup Box Delete (66D)
Includes:
• Heavy service front springs (200 lbs. Upgrade above the spring
computer selected as a consequence of options chosen. Not incl. if
maximum springs have been computer selected as standard
equipment).
• Rear stabilizer bar
• Rear auxiliary springs
NOTE: Salesperson's Source book or Ford RV Trailer Towing Guide
should be consulted for specific trailer towing or camper limits and
corresponding req. equipment, axle ratios and model availability


HEAVY SERVICE SUSPENSION PACKAGE (67H)
Usage:
• Recommended only on vehicles which will permanently utilize
aftermarket equipment such as heavy duty winches, brush guards or
other apparatus which loads the front axle to the specified Gross Axle
Weight Rating (GAWR)
Availability:
• Optional on all F-250 Pickups
Not available with:
• Snow Plow Package (473), Camper Package (471) , Stabilizer Package
(63B) or Heavy Service Package for Pickup Box Delete (63R)
Includes:
• Heavy service front springs (1 up upgrade above the spring computer
selected as a consequence of options chosen. Not incl. if maximum
springs have been computer selected as standard equipment)
NOTE 1: May result in deterioration of ride quality.
NOTE 2: Vehicle ride height will increase w/the addition of this
package.

SNOW PLOW PREP PACKAGE (473)
Availability:
• Optional on all F-250 Pickups
Not available with:
• Heavy Service Suspension Package (67H)
Requires:
• 4x4
Includes:
• Computer selected springs for snowplow application.
• Extra Heavy Duty Alternator (67D) w/Power Stroke® diesel engine
• Unique fan clutch w/Power Stroke® diesel engine for improved cooling
Options Available:
• Dual Alternator (67A) (Diesel only)
NOTE 1: Restrictions apply; see Supplemental Reference or Body
Builders Layout Book for details
STABILIZER PACKAGE (63B)
Availability:
• Optional on all F-250 Pickups
Not available with:
• Camper Package (471) or Heavy Service Suspension Package (67H)
Includes:
• Heavy service front springs
• Rear stabilizer bar

 

No, swapping the blocks is an easy job. If you live near Wisconsin, I'll ecen swap my F-250 blocks for your F-350 blocks! I'll even help you install them.