Im not following you, it states the 250 axles are 1.50"dia with 35 splines vs the 350srw being 1.57" with 37 spline. Really arent big numbers, but i suspect that is how the payload rating on the 350 is about 1k lbs higher.
Other than that the tubes, housing and ring/pinion are the same.
The drw 350 is a bigger axle as it is a dana 80, what is suprising is that the 350drw and 450 use the same axles.
The axle shafts in a full-float rear axle, which the Sterling 10.50" and Dana 80 both are, do not have anything to do with the axle's ability to carry weight. The weight the axle carries is all carried on the housing, bearings and hubs. All the axle shafts do is transfer torque from the ring gear carrier to the hubs. So larger diameter axle shafts have more to do with the axle's GCWR or input torque rating, rather than the GAWR.
The F350SRW's increased GVWR and RGAWR is the result of higher rated springs, as well as higher rated wheels and tires.
As far as the Dana 80, it is currently used in the F350DRW pickup and cab/chassis trucks, as well as the F450 pickup. It is not used in F450 or F550 cab/chassis trucks. Those trucks get the heavier Dana S110 axle.
Yea i have seen that but have read that its been checked and that larger axle is really for the drw trucks
Yes, I have read that too. Basically that the axles with 37 splines is in the wrong column and should be under the DRW heading. I asked our parts guy at the dealer and he said same part number for 250/350 rear axles. Doesn't matter to me either way...
Not sure either, but I would find it hard to believe that the F350SRW's Ford 10.50" axle uses shafts with a different spline count than the F250, using the same model axle.
you seem to be the superduty axle expert
Are there any differences between 2011250 and 350 axles?
Fords documentation shows they are but i have read that they were really the same and different only on the drw
I do not know the answer to that question, but I suspect they are the same.
Yes, it is entirely true that the DRW uses a completely different axle (Dana 80), than the F250/350SRW (Ford 10.50").
I would put some weights on the front bumper and not worry about it.
2005 Chev 5.3 Supercharged 395HP 425 T hp. Two wheels on front, 2 on back. one seat, tint windows. front and rear bumpers, headlights, windows. Door on each side. Heater, floor mats, 6 Reese candy bars, junk behind seats, some dirt. Pulls so hard.
F250 and f350 wheels/tires are the same, depending on what options you have, mine has the fx4 package with the 20" wheels and "e" rate michelins. These are the same as the f350 on the lot had.
SPrings are definetly different in the rear.
Fortunatly i was wrong about the axle shaft sizes as someone pointed out the pdf from ford has the dia/spline count in the wrong columns.
Supercharged....not sure if you were trying to be funny, but i will pass on hanging more weight on the front of my truck...being a diesel its already heavy enough!
Very true that you can order a new F250 with the optional wheels and tires, equal to the F350. Has been true for some years.
Both trucks come standard in the XL trim level with 17" steel wheels. The F350 has only a slightly higher RGAWR with 17" wheels, versus the F250. I think it's about 6400 lbs or something, I forget. When ordered with 18" or 20" wheels, the F350 has a much higher RGAWR, 7000 lbs, than the F250's 6100 lb RGAWR. The extra 900 lbs is a huge difference, even though, in reality, the F250 has most of the same parts, except for the springs.
Don't mind Supercharged. He is famous for saying nothing anyone can make sense of. Though his counterweight idea actually isn't a bad one...
SW isn't metal. It takes brakes, power and the resulting weight of those things to improve towing capacity. It takes stiffer frames to control the stress put on by heavy loads.
I always have to smile inside when I effortlessly pass some pretty little 1/2 ton truck struggling to maintain momentum and keep from swaying all over the road on our local mountain pass.
Probably just need a SW update.
Software is the key to ability to use materials much more wisely.
Hence, far fewer amounts of metal (or material) is needed to do the same job, and correspondingly, less brakes, power, and weight during both the design and actual use phase.
Frames / structures can be made stronger, stiffer, and yet be lighter from the design stage.
Welcome to the late 20th Century.
Active software management of stress and loads is the next big revolution in auto and truck building.
With active management, parts can be built to fatigue life of specific numbers of cycles rather than be overbuilt, and the cycles counted.
You will visit this technology every time you board a late model aircraft.
All large commercial aircraft is built to a set number of takeoff landing cycles and hours.
Use it up, and it is scrapped.
This kind of design techniques will be applied to all high volume vehicles within 20 years.
A plausible guess is vehicles can be made 30% lighter over the next 20 years and do the same job, carry the same load, or the load can be increased 30% (easily) for the same weight and form factor. 40% without trying much.
For a preview, take a look at the 6.7 Ford CGI block and ask yourself how they shaved so much weight, but yet made it so much stronger.
That engine employed active management of stress at a far more advanced level than previous engines.
It has been my experience that over the years...say since the 1960's...designs and correspondingly the amount of material used in the manufacture of vehicles has focused more on how much material can be pared away in the design and manufacture of many items...in order to save on the cost of manufacture.
I think computer assisted design can be a wonderful tool, but like any tool it depends on who is using it and what their goal happens to be.
I have felt that in far too many cases, CAD has been used to determine what the minimum strength for a component can be...rather than determining what the maximum strength a component may need to be for it's role.
I'm not saying this is the absolute case...as I am not privy to meetings by higher echelon staff at different manufacturing businesses.
When it comes to vehicle stresses designed by CAD...a GM advertisement comes to mind where the Ford and the Chevy one ton pickups are compared.
In one test, in the film...you can see the chassis undergoing twisting stresses and in one pickup's case....there is a pop...and a dent appears in the body of the truck box....seemingly as a result.
I wonder if some more strength and resistance needed to be designed into this box design to prevent the pop and resulting dent.
I sometimes wonder, that in the manufacture of any item.....bean counters and engineers engage in debate over customer needs, strength requirements to fulfill those needs and the and the never ending attempt to balance cost/profit margins.....and if CAD is used as a perhaps, a more precise tool to rationalize lighter construction.
However marketing also get's involved and marketing needs to be able to promote advantages over the competitor, in order to sell the product.
So here we have 3 factions...engineers....bean counters....marketers.
Marketing means sales (money) and bean counters mean paring costs (money), while engineers focus on developing the product
Three factions...two of the three with a similar focus...who will carry the day ?
When I discuss CAD as a more precise tool...I don't automatically mean more accurate, as my understanding of computer aided design is that the computer program needs to have good, accurate input...in order to have good, accurate design.
When determining design parameters...who is involved in developing these design parameters ?
Just engineering staff...or other manufacturing factions ? How are all the goals of these factions accommodated ?
I dunno ?
Just some thoughts.
* This post was
edited 04/19/12 12:54pm by Lessmore *