# Super Duty(s) Comparison



## Pelican (Nov 16, 2001)

I've mentioned a number of times that the same front axle is used amongst the F-250, 350 and 550s, and have been met with skepticism, so here I offer how I came to this conclusion.

In prepping my F-550 for the body company, I noticed a number of the components looked very similar to my F-350 SRW, so I did a detailed side by side comparison, and included my buddy's F-250 pickup. All are PowerStroke 4x4 models.

Frame: Both the 350 & 550 have the same frame rails, the same stampings in all the same places. I don't have calipers to measure the gauge, but they appear similar to the eye. I can't comment on the F-250, my trucks are both cab & chassis models, I only have F-250 pickups, a foot shorter, to compare to.

Front axle: Both my 550 and my 350, plus my buddy's 250 pickup have the same casting numbers on the housings. The steering components are all identical, except the passenger side tie rod end on my 550 is stamped F-450 for some reason. I have seen comments that the internals are different, I believe this is limited to the gears, 4.88s in the 550, 3.73 or 4.10s in the 250 & 350.

Transfer case: All identical.

Transmission: My 550 and the 250 have identical 6-speed trannies, my 350 has the auto.

Rear axle: Here's where things take a different road. while the 250 and 350 share the same axles, the 550's is almost twice the size of the other trucks'. The spring shackles are either cast or forged on the 550, while the 250 and 350's are stamped steel. The spring stack is bigger on the 550 too, but the springs on the 250 & 350 appear identical. The 350 has bigger spacer blocks, giving it 2" more clearance.

Wheels & tires: Another obvious difference. The 550 carries 19.5" wheels and tires while the 250 & 350 carry 235/85/16 & 265/75/16 tires respectively. The 250's tires can easily be upgraded to those of the 350 or better. I've come across G rated 235/85/16s that exceed the rating of the 350's larger tire, but the tread is not conducive to plowing.

Brakes: The 250 & 350 share the same components again, while the 550's are visibly much larger.

The point: I've seen a number of threads where concern is expressed at overloading the front axle, but here we see that the same components are used on a truck with a GVWR 7600 lbs heavier than the 350's. While you may exceed the manufacturer's maximum front axle weight *rating*, the *physical* capacity is much greater, the tires are the limiting factor. If you upgrade the tires, it is my feeling that you can safely mount any plow to either truck.


----------



## chtucker (Sep 6, 2002)

http://forums.thedieselstop.com/ubb...imit=100&Old=allposts&Main=474991&Search=true

http://forums.thedieselstop.com/ubb...d=allposts&Main=471856&Search=true#Post471858

I don't disagree with your observations... but there are people out there with dana 50s, Both of mine unfortunately.


----------



## Brickman (Jun 17, 2002)

From the Code give on one of the links above I have a Dana 50 in my F 250. Damn. Here all this time I thought I had a 60. 

Does any body know the code for determining what axle is in the rear.


----------



## chtucker (Sep 6, 2002)

They are the same in the 250 350 SRW (maybe duals too) 10.5" sterling (ford made) in the 99 and newer Superdutys... the pre 99 (97 if you want to get serious, because there wasn't a 98 250HD or 350HD) had the 10.25" sterling. Both very similar and can utilize some of the same internals (lockers and such)


----------



## Hoopsfan (Aug 15, 2002)

*Pelican*

Great info, but any idea why Ford won't warranty the diesel F350 CC with a plow? I have no doubt the truck would handle it. Being new to Ford, maybe I'm missing something.


----------



## Pelican (Nov 16, 2001)

I've been trying to figure out their reasoning, it doesn't make sense to me. I understand that a crew cab would be heavier, but a plow would still keep the truck under GVWR. I'm willing to bet the safety police and attorneys have something to do with it.


----------



## Nailit1954 (Mar 6, 2002)

Pelican
From reading the post lately you seem to me saying that the F350 psd is the best value? I believe you own both F350 and F550 , what is your opinion?


----------



## Pelican (Nov 16, 2001)

Nailit, it would depend on your requirements. In my opinion, the F-250 with the Dana 60 front axle is the best value, there is virtually no difference between it and the F-350 SRW other than ground clearance, which is accomplished through the use of 2" higher spacer blocks.

My 550 cost $4000 over my 350, and basically the only differences are rear axle, brakes and wheels/tires. I was expecting a bit more for the premium.

I'm not saying you should load up a 350 to 17,500 (though I often did with my '97), I don't think the rear axle can handle it. It does seem, however, that the front axles of the 250 & 350 should be able to carry the same loads as the 550, although the tires are not up to the job.

One thing I forgot to mention above: All three trucks use the same number and size of wheel studs to secure the wheels.


----------



## Nailit1954 (Mar 6, 2002)

Pelican

Points well taken! Thanks for the reply.I 'm very happy with my 97 F350 psd 4x4 dump with a boss 9'2 v plow that is my daily driver. I't used in my construction buisness,(suits me fine.) Between dump runs with roofing etc.and plowing in winter time, it works for me!
ps. I like the old style body for plowing,more square any thoughts


----------



## Pelican (Nov 16, 2001)

Believe it or not, I think my '97 was more comfortable than the Super Dutys. My seat bolsters rub me in the thigh, and the shift lever on the 6 speed rubs my leg in reverse and low. It also seems like the seat is too far from the door, I usually lean on the door to look out the window while plowing, and this is uncomfortable.

I do appreciate the conveniences in the new trucks however. My old trucks were XLs, I sprung for XLTs with the Super Dutys.

The only real trouble my '97 gave me was spitting out three teeth on the rear ring gear, I'm still trying to figure out what caused it. I know how to drive heavy trucks, (I've grossed as much as 125,000, dump trailer) and never horsed the truck. I serviced it regularly too. I got the 550 so I wouldn't have to put a V box in and out anymore, and to increase capacity.


----------



## Brickman (Jun 17, 2002)

Chev/ Dodge butt whupper.


----------



## Pelican (Nov 16, 2001)

What a sleeper! Do you pull 5th wheel trailers?


----------



## Brickman (Jun 17, 2002)

> Do you pull 5th wheel trailers?


99% is this trailer with 3 or 4 cars. I am working on other things to haul. Trailers, compact Kubotas, etc.


----------



## Guest (Oct 8, 2002)

Brickman,

You need to level that thing out  

Nice rig!

Just put some new modified injectors in mine Fri. All I can say is 

Greg


----------



## Brickman (Jun 17, 2002)

> _Originally posted by Dockboy _
> *Brickman,
> 
> You need to level that thing out
> ...


Level out what? the truck? It sits like that because of the air bags. Add trailer and 4 cars and it sits nice and level. I have the on board air compressor on order. So I can dump the air when I am empty, and then pump it up for a load with out having to look for another air source. Air gauge and switch in the cab, sweet.

 on the injectors. I love Go fast toys, dang I wish they wouldn't make em so $$$$$$$$$. Right now I got a 75HP chip on it, propane to put on. The next thing as soon as I can afford it will be gauges for pyro and boost, and 4 inch exhaust. Not sure yet which order they will happen.


----------



## Guest (Oct 8, 2002)

Brickman,

An egt gauge is a must towing what you do with a chip

When my truck was stock with a 54hp chip, I could get to 1300 degrees towing 10k lbs. with no problem. Having the gauges lets you know when to feather the throttle on those long uphill pulls. Otherwise it can be Bye-Bye turbo :realmad: Don't know if you have a 6-speed or auto? If it's an auto, get a tranny temp too! You would be amazed at what is happening when you can see it!

My 4" exhaust lowered my egt's by a good 200 degrees 

I'm getting my chip(flip chip) retuned for the new injectors. I could hit 1600 degrees pre-turbo in extreme(130hp) without blinking an eye But boy is it FUN!!!

Greg


----------



## szorno (Jan 3, 2002)

*axle question*

Hey Pelican,
If I am understanding you correctly, your F250 SD with psd and your F350 SD srw have the same frame, front and rear axle, just different springs in the rear? If that is true, then I can relax my search for an F350 SRW used, and just go for a 250 and add air bags and E rating tires. (save mucho dollars) I have a 350 gal mag chloride tank I need to put in the back and 8 ft plow for front. That requires a GVW of about 9500. 
Your thoughts???

(rig currently on 86 chevy 350 with 12K gvw)


----------



## Brickman (Jun 17, 2002)

Dockboy I got my propane on finally. The green beast becomes even meaner. As the Didges and Crapamaxes fade into the smoke of the exhaust.  Waiting to see what happens with the hauling, I am expecting it to be bad azz there too.


----------



## Guest (Oct 28, 2002)

Brickman,

  

I've driven some trucks with the "pane"! Pretty awsome!!!

I've been concentrating on getting as much HP as I can on #2 alone. Just put a BIG set of injectors in. Unbelievable power! We still have to work on tweeking the idle a little though. I have a Race-Technology meter(similar to a G-tech only much better and more accurate) and did some 1/4 mile comparisons:

Stock, 4" exaust, Tymar air intake
16.94 @ 80.8 mph

Stock, 78hp Diablo chip, 4" exhaust and Tymar
16.19 @ 87.2 mph

BIG injectors, Wastegate disconnected, No chip, exhaust and Tymar
14.82 @ 93.4 mph

 

Greg


----------



## Brickman (Jun 17, 2002)

I had a 78 HP Diablo chip. The first one I got. That had a neck snapping power burst. The Bully Dog chip I got now and the propane kick in the power and go from there with out the burst. My chip dealer says that is better, easier on the power train.


----------



## Guest (Oct 28, 2002)

Which propane kit did you get???

Greg


----------



## Brickman (Jun 17, 2002)

Bully Dog. 80 HP and 250 lbs of torque.

www.bullydog.com


----------



## Pelican (Nov 16, 2001)

szorno, you have it correct. I can't recommend that you exceed the manufacturer's weight ratings  , but the components are the same (assuming you have the Dana 60 up front) between the 2 trucks. Beware the DOT will not acknowlege the improvements you've made, and will still reference the door sticker for GVWR.


----------



## Mike 97 SS (Aug 11, 2002)

Dockboy, you crack me up, you have a 4x4 snowplow work truck, and you got it doin 14s in the 1/4 mile, LOLLL   :waving: Mike


----------



## Brickman (Jun 17, 2002)

> _Originally posted by Mike 97 SS _
> *Dockboy, you crack me up, you have a 4x4 snowplow work truck, and you got it doin 14s in the 1/4 mile, LOLLL   :waving: Mike *


Poor boys can't afford two, so gotta make do with one for work and play.


----------



## Rob (May 15, 2001)

Pelican,
Can you go to the DOT and have the weight rating up'd ? Quiate a few years ago, a buddy got pulled over for being overweight. (he had an F100, and put 2 skids of cedar chips on it !!) Anyway, he got pulled over, weighed and ticketed. He was able to go to the DMV and have his GVW increased. He didn't even have to show proof any work was done to the truck. So, he showed the new weight sticker and got out of the fine. That was quite a few years ago, so maybe that isn't done anymore, but I was wondering if the DOT will recognize any of your mods if you go through the system.


----------



## Pelican (Nov 16, 2001)

I think the laws may vary from state to state, here in NY you must have any mods certified by a registered shop to make any change in GVWR, this according to NY DMV. Trouble is, I haven't been able to find a shop who will assume the liability of making these modifications.

I talked with a guy up in Canada, according to him, they can register their trucks for any weight they wish, over GVWR or not. They pay by the pound for registering, but face heavy fines if they are overweight, the guy I spoke with had a 11,000 GVWR truch registered for 16,000
Wish things were that way here.

When I used to drive trailer, Conn. was one of the toughest states as far as DOT was concerned. I'd be surprised if the same laws you describe remain today.


----------



## Brickman (Jun 17, 2002)

Pelican that is the way DOT is around here. Add the truck capacity, and trailer to come up with a DO NOT EXCEED weight. My truck is registered for 29800 which the two combined. They don't seem to care that Ford says 20000 GCWR. That is WY any way. Another state might hassle me.
It sure sounds like CT DOT is bad if they are hassling the guys in their pickups and 350 - 550 trucks hauling sand and grass clippings. You would never see that here or in CO. Atleast I have not seen it or heard of it.


----------



## plowking35 (Dec 21, 1999)

In fact some days in CT all they target is the below CDL type trucks. I have at times seen 50 or more light duty trucks pulled over at an inspection location.
Dino


----------



## Guest (Oct 28, 2002)

Mike,

A guy has got to have some fun 

You ought to see the faces on the kids with rice burners when you pull along side with a truck full of wheelbarrels, concrete forms, towing a mixer and then leave them in black cloud of diesel fumes. It's great 

Greg


----------



## chtucker (Sep 6, 2002)

The whole area is archaic... (Oh and I grew up there, Wilton to be precise)

Lets see:

Can't drive my pickup on the parkway (NY) unless it has a topper
Not supposed to drive my Excursion on the Parkway (>8500GVW)
If you want to drive you cargo van on the Parkway, just put in some "parkway windows" 

I much prefer the west! I can drive any off road vehicle on the street as long as I am headed out to go off roading (snow mobile, atv, dirt bike)
Never have and never will register my skidsteer and drive it everywhere (don't even own a trailer)
NEVER have seen a pickup pulled over for a weight violation. 
I don't even think it is legal, but no one stops you if you run a tandem, For example: Excursion, 20 airstream, 10' flatbed trailer with 3 atvs

The west pretty much lives up to its reputation of self-responsibility. As long as I don't hurt anyone, I don't have any problems. if I hurt myself, its my own dumb fault. 

Howard


----------



## Mike 97 SS (Aug 11, 2002)

Hey Dockboy, does this look like the ricers facial expression ---> , or is it this one ---> LOL Mike


----------



## Brickman (Jun 17, 2002)

> _Originally posted by Mike 97 SS _
> *Hey Dockboy, does this look like the ricers facial expression ---> , or is it this one ---> LOL Mike *


I got the one, the face is red, and there are TWO fingers in the air. But Rooster would can me if I put it up.  
Much as I like to rag on ricers I know the ones in the Fast and Furious movie would kill my truck.


----------



## KatWalk (Oct 12, 2002)

*Daul rear wheels*

I currently have a 97 GMC 3500 4x4 dually gasser. I wanted to know that when I buy my new ford, do you all think that the f350 4x4 diesel dually will do the same job as the f450 or 550. I don't do any long hauling. I am talking about hauling 2 pallets of stone, 3-4ton of crushed stone. If I put 3 ton of crushed stone in the GMC......forget about it . Squats like a girl. Everything is local and similar to chtucker I rarely see DOT with smaller trucks. Can I save some money with the f350?? Thanks. Ryan


----------



## chtucker (Sep 6, 2002)

NO.

The 450s and 550s have larger rear axles than the 350s. Two pallets of stone and you will need the higher rated axle, bigger brakes and higher rated tires.


----------



## Pelican (Nov 16, 2001)

KatWalk,

Legally? No.

Will the truck handle it? Mine did. I had a '97 F-350 dump that I regularly carried 4 tons of item 4 in. I would also transport 3 pallets of Unilock bricks regularly, at 3000 lbs. per pallet. I had the truck for 5 years with no problems except just before I sold it. The rear ring gear spit out 3 teeth for some reason, I think it may have been due to a new driver. If you're experienced with hauling heavy loads (no jack rabbit starts) you should be OK. It does take its toll on the truck over time though and tires wear out quickly.

The price difference is about $4000, and your fuel milage is cut by 25% due to the lower gearing with the 550.


----------



## KatWalk (Oct 12, 2002)

*Just the two I wanted to hear from*

Thanks guys.....I know the legal end of it but wasn't positive about the technical end. I had an 88 superduty dually 460 gas that would carry 4 ton of stone and the 97 gmc at the same time!!! Payload wise, I don't think that I have a choice except going with the ford. I was planning on the auto trans. Any how, thanks for the input. Ryan


----------



## John DiMartino (Jan 22, 2000)

Pelican,thank you for all the good info youve posted on the 99 and newer SD's.It is very useful to me,since I am looking for a used one next yr.If you have the time,can you see if the steering boxes are the same,and the master cylinder is the same.If they are you could basically make an F550 outo f a F250,buy swapping in the F550 axle,and 19.5 tires.Also you said the front axle was the same,but are the brakes/rotors the same on the front end of the Dana 60 F250/350 as the 550?I would think the 550's would be bigger.If they are the same the swap is even easier.I am impressed if the frames are the same,in every aspect. Dockboy how do those new injectors run?,how much do they smoke . I am fabbing up twin turbos this yr,good thing is I'll pick up about 40-50hp,should drop 300+ EGTS,may lose some smoke though.Mikes 97SS,you should see guys when i beat them with my work truck,Ive had guys slamming their dashboards in disgust,just cant believe they are getting beat in there new Camaro SS by a 7000 truck.Imports are even more fun. The Dodge/Cummins are wicked out of the hole with 4.10 gears and 25PSI launches .Havent had anyone stick with me on the street out of hole yet.


----------



## Mike 97 SS (Aug 11, 2002)

I'll run ya!  :waving: Mike


----------



## CT18fireman (Nov 30, 2000)

John the axle is the same but the 550 carries much larger rotors and calipers. I will measure them for you when I get a chance, unless Pelican beats me to it. The steering boxes are identical. The master cylinder looks the same but a friend told me the piston may be larger to handle the bigger brakes. Make sense. I cannot read a part # on either master. Might take a call to Ford to see if there is a difference.

The rear axle and as well as springs all around are the main difference as Pelican has stated. I know that the addition of 550 fronts to my 350 made a big difference. I was going to add them to the rear but being a pickup wanted to keep some ride quality. 

Going from a 350 to a 550 you really can't tell much difference except that one is a dual wheeled dump. They ride and handle similiarlly, even when loaded.


----------



## JohnnyU (Nov 21, 2002)

Is there no difference in frames? I would think that an F550 would need a stronger, or differently designed, frame than the much lower gvwr F250/350.


----------



## Pelican (Nov 16, 2001)

Yes, the frames are identical to the eye, and by the tape measure. I don't have a micrometer, maybe CTfireman does and can measure the gauge of each frame rail. This is the only part I'm not certain of.

John, if the frame rails do turn out to be the same, then yes, I believe all the other parts will bolt on. Just make sure the 250 you're using has the Dana 60 instead of the 50. You'll need to change the gears in front to the 4.88s in the rear, or from what I've heard, 4.10s are available in aftermarket for the rear axle. I think the 250 will have 3.73s.

If you're going 4x4, then I think 4.10s would be plenty low enough for normal use, then you've got low range left for some real grunt. The 4.88s in my truck make the motor spin at 2200 at 55, and dropped fuel milage from 12 mpg in my F-350 dump to 9 mpg with my 550.

Katwalk, I'd stay away from the auto if you're going to haul a lot of heavy loads, especially if the region you are in has a lot of hills. If I had to pull a long hill with my load with my '94 F-350 auto, I'd stop and shift to low range to ease the burden on the tranny. Even so, it blew at 3 days over warranty, and cost $2200 to fix! I sold it as soon as it was repaired.


----------



## Brickman (Jun 17, 2002)

John D. my PSD with 75 HP chip and 80 HP shot of propane is still pulling so hard at 100 MPH that it scares me. No joke.


----------



## CT18fireman (Nov 30, 2000)

Frames are the same thickness material. No obvious signs of reenforcement anywhere on the frame rails.

I would think the fron brakes could easily be upgraded to the larger rotors and calipers. I may look into doing this for my 350 anyways. It would mean purchasing the larger wheels though. The rear axle is the only major difference that I see.


----------



## KatWalk (Oct 12, 2002)

*PELICAN, You are the Best!!!!!*

Thanks for the continued input....not only on my question but for everybody. I want you to know that I am running one truck true ******* stylin'......91' Chevy 2500 2WD beefed up to a one ton suspension(old lumber yard delivery truck). Truck had a $600 body work and paint special.....no tailgate and bed remained the original color. Red bed....everything else is white. 161k on truck. Read on please!!!! Airflo 1.7yd. sander mounted on 2"x10" frame to allow enough clearance for the long chute designed for a dump body!!!! Sander controls rest on the seat next to me and I wired them to the dome light in the cab. Less than impressive t the normal folk!!!!!! thanks again for your help. Ryan


----------



## Shady Brook (Sep 8, 2001)

I have just been pouring over this stuff myself. 

This is from the Ford Diesel site from one of the Studs. The Frame is thicker on a 550. If you go to the site you can check differences on 450's as well. 



"F-350 DRW chassis cab vs. F-550 chassis cab, both with regular cab 4x2, 140.8" wheelbase, 60" cab-to-axle, PSD, and std payload pkg.

The cab, engine and tranny are the same. The front suspension is similar but different on 4x4s, and a lot different on 4x2s (F-350 4x2 has coil springs and twin I-Beam front suspension while F-550 has leaf springs with monobeam front suspension. The big difference is tires&wheels, brakes, differential (rear axle), rear springs, and - yes - frame.

GVWR 12,500, 17,500

max front GAWR 4,550, 6,000
front axle 4,850, 6,000
front springs 4,550, 6,000

rear GAWR 9,750,13,500
rear axle 9,750, 13,500 (Dana 80 vs. Dana S135)
rear springs 9,750, 13,500
rear spring pad thickness: 3.89 vs. 6.66"

brake rotor front 13.03", 14.53"
brake rotor rear 12.83", 15.55"

frame section modulus 8.7 vs. 10.1 (No options for F-350. For F-550, the frame gets much heavier - up to 19.3 - with longer wheelbase or 19k GVWR pkg.

wheels 16x6k vs. 19.5x6k

---------------

If 4x4, then the F-350 front suspension is closer but not the same:

max front GAWR 5,200, 5,600
front axle 5,200, 6,000 (both are Dana 60 so the outside case is the same)
front springs 5,200, 5,600
front spring thickness: 1.18" vs. 1.25""


----------



## Pelican (Nov 16, 2001)

*2002 vs. 2003*

That looks like something Smokey would post...

I had my 350 in to the dealer today for a seatbelt recall and took a look at the 550 dumps he had out front. He had one '02 and two '03s. MSRP on the '02 chassis was 38,900 while the '03 was 41,200. They were all XLs with Powerstrokes. The '02 was the 7.3, the '03s had the new 6.0 All had automatics, but the '03 version carried a $1600 price tag while it was included with the '02.

All other options were the same, quite a price hike for the new trucks!


----------



## Shady Brook (Sep 8, 2001)

Good eye Pelican! That was Smokey.

The 6.0 and new Trans is supposed to be awsome. Worse yet, I think there are rebates for the 7.3 powered units, but not for the 6.0. So really it could be more like a $4,000 difference.

I would love the 6.0, but fear being a Guine pig.

Jay


----------



## Pelican (Nov 16, 2001)

Shady Brook, if you haven't seen this thread , take a look. I drove a prototype over the summer with the new engine/tranny combo and it was pretty impressive.


----------



## Brickman (Jun 17, 2002)

> _Originally posted by Pelican _
> *Shady Brook, if you haven't seen this thread , take a look. I drove a prototype over the summer with the new engine/tranny combo and it was pretty impressive. *


Very true. I drove one my self and WOW!

I wouldn't mind having a 6.0 but am not ready to be a tester.


----------



## Shady Brook (Sep 8, 2001)

It does sound mighty fine. I am afraid to test one, I am sure I could be swayed to do something stupid. Maybe if I can weight a year or so to get any bugs worked out.

Jay


----------

