Titan drive shaft vs Ford

[kj22250]

I crawled under my truck the other day and noticed how big the diameter of the drive shaft is. I bet it is 4-5 inches wide. So then I looked at my dad's '03 F-250 Powerstroke drive shaft and it's probably 2-3 inches in diameter, the typical size. I'm sure both are hollow but you would think the heavy duty Ford would be bigger. Can anyone explain this?


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'05 KC SE 4x4 Red Brawn

[drags1998]

First of all,WHO said the FORD is MORE HEAVY DUTY!!!!!!! haha!! Sorry I could'nt help myself!!! This is one case where size dosent matter!!!!

[Ape0r]

There are a lot more variables than just overall diameter. You don't know how much, if any, is bored out of the middle of either driveshaft, and you do not know what materials are in each driveshaft. The bottom line is that as long as the shaft is strong enough to resist bending or breaking, then it should be as thin and light as possible, so as to increase overall payload capacity.

[kj22250]

That's interesting, I'm sure there are many complicated engineering implications going on here, but by looks I prefer Nissan's.

[smoothTitan]

the silverados are the same way, looks just like the titans

[Titan4x4Aggie]

my guess: ford's is steel (stronger, stiffer and heavier, but harder and less likely to fail from fatigue) whereas nissan's is aluminum (weaker and not as stiff but lighter. also softer and more likely to dent, and later can fatigue since aluminum does not have a fatigue limit.)

with a larger diameter, the wall thickness is reduced (increasing the likelyhood of a dented / bent driveshaft) since with a larger diameter, the shear force of the drive-torque is reduced, thereby allowing for a smaller wall thickness of the shaft.

pro's and con's to each design.

[mikegronholz]

HMMM ... seeing as how I believe I am the only one to change driveshafts on the Titan so far ... I will lend my $0.02

The titan drive shaft is a hollow 5" aluminum shaft that narrows to 4" at the transmission.

When we had mine recut for the lift, there was a decision to be made ... 5" hollow aluminum, or 3" hollow steel ? I went with steel for a few reasons:

Strength: Steel will bend long after aluminum will (not that I would ever get to that point anyway)
Strength again: Ding the shaft some how (rock or whatever), the aluminum will give and now you have to re-balance the driveshaft ... steel will bounce off of it

That is about it. Now aluminum definitely has some pros over steel:

Weight: weighs WAY less (about 1/2 in this application)
Looks: Will not rust (my steel is coated in POR 15 so no worries, but you get the idea)
Looks again: Nissan was going for "big and bad" ... 5" over 3" is a massive difference
Rotational Mass: The more the mass, the more energy it takes to move = less rwhp/rwtq (mine is negligable at best)

I think that about gets it ... now, as for me, if I could do it over again, I'd pick steel all day long. Look at the rock crawlwrs out there ... they pick steel for a reason.

And for those really wondering what the factory shaft looks like disassembled ... here you go ...