What's the difference btwn a W250 and a W350 SRW front axle?

[Niki]

I just noticed this over the weekend, on the stickers under the hood, my W250 says 4500# front axle, my W350 SRW says 5000#, what's the difference? They both look the same to me, both are 3. 54, both are Dana 60F's...

 

[Steve Graham]

My best guess would be spring rate. All of the internal parts should interchange.



Steve