2-speed vs. double reduction

[linesplice]

Can someone please explain to me what the difference between a two speed rear axle and a double reduction rear axle is? I'm terribly confused.

 

[mangus580]

A 2 speed axle has 2 different gear ratios you can choose from with a selector switch.

A double reduction is just that, a 'double reduction'. It has essentially 2 gear reductions between the input and the output. This method only has one over all ratio though, between the input and the output.

Hope this makes sense...

 

[Flatlander]

The pinion drives an intermediate gear which drives the big bull gear, so two reductions...

 

[linesplice]

I see. So, given the two reductions, does this automatically indicate a higher numerical output gear ratio? Why have a double reduction at all if you can simply change a normal gear ratio?

 

[rizzo]

http://www.freepatentsonline.com/6886655.html

using double reduction you can reduce the size or your gears. below is a pic of rockwell 5 ton gears. you can see the size difference. imagine if they wern't double reduction gears.

having the the gear reduction box on top of the axle also helps the driveline angles and keep the seals and rest of the driveline up out of the water and mud

I don't know why rockwell did the double reduction, but those are advantages that I see.

 

[Trango]

Intuitively, I'd say this was done for driveshaft clearance as well as the aforementioned ground clearance.