why aluminum?

[oldboyscout]

I'm still trying to decide between a Kubota B2920 and L2800. Irealized that besides the "component bolted to frame" of the B's and the traditional solid casting of the L,
the B's have aluminum rear ends.
What is the purpose of that?
Usually one would use aluminum for lightness, but in a tractor that's counterproductive

 

[dfkrug]

That's a good question. At least with the smaller tractors, like
Kubota's Bs, there are competitor machines (e.g. JD 2xxx) that use
cast aluminum in structural areas.

OTOH, Deere is the only company I know that uses cast Al in major
structural areas (rear axle housing and gearbox) for tractors in
Kubota's L class (2500-3500#).

I went into this at length during my repair of broken Al castings in my
JD4300 project, and I have asked JD directly about this. No answers.

 

[teg]

...Usually one would use aluminum for lightness, but in a tractor that's counterproductive...

Unless you want to mow the yard weekly with it...

What are your main use going to be... You can always add more weight.

 

[RoyJackson]

Main thing is low cost of manufacture.
My 4400 has those aluminum castings...and yes, I'd prefer cast iron or cast steel. But there's a heck of a lot of these Deere machines around that have never had a problem.

 

[oldboyscout]

I would have expected the aluminum to be more expensive!

 

[pat32rf]

While the cost of raw aluminium may be more, the cost of casting, machining and TRANSPORTING the aluminium castings, both before and after assembly is probably less. Plus, as has been mentioned, you can always add weight....
I just wish they had thought of the corrosion on those steel brake levers going thru the aluminium casting and used bronze inserts somehow....

 

[oldboyscout]

Oh Geez....now I want the L2800 instead.....

 

[dfkrug]

Main thing is low cost of manufacture.

I am not so sure of that. Modern cast steels may require higher
temps to cast, but are very machinable. Material cost is much lower
for steel, of course.

I can't see the transport costs being a significant difference since
container and trucking costs are volume-based, except for extremely
dense cargo.

What stands out is that other makers of this class of tractor do NOT
use Al.

 

[oldboyscout]

Are there known instances of unusual wear or damage to an Aluminum tractor due to heavy use (not abuse)?

 

[dfkrug]

Are there known instances of unusual wear or damage to an Aluminum tractor due to heavy use (not abuse)?

It is hard to say. What constitutes abuse? Some would say rental
service is abuse, by definition. Sometimes, perhaps.

Anyway, both of my JD4300s have had broken axle housings when they
were in rental service. One I fixed, and the other got a new housing
installed by Deere.