JD 2520 Snapped Axle

[dfkrug]

BTW, I think most ferrous castings on tractors are cast iron, not cast steel.

Why do you say that, Roy? Can you site a source?

I have tried for years to get more info from tractor makers on the cast
ferrous alloys they use. There are lots of grades of cast iron out there
(grey, white, malleable, ductile), and cast steels, too. Pretty much if you
get the carbon below about 2%, you have steel. Above 2%, cast iron.

I can tell you from my experience that the cast iron/steel used in my JDs
is quite soft and machinable. And clearly cast, not forged.

As for small sub-2000#-class CUTs, like the OP's JD, a number of them
use cast aluminum for structural elements, but I have found no current
CUTs in the 3000#-class that use Al castings, except the JD 3x20s
and some of the JD budget units.
(I even brought my magnet with me to the World AG Expo last month.)

 

[glc24]

I don't think I abuse my equipment,

Well,IMHO,you would have to ask yourself why I had 4 major failures in 160 hours. The poor thing isn't even broken in yet.

Do you think I have a "lemon" and should seek remediation with my local dealer?

You're either asking your 2520 to do tasks it isn't designed to do,or you're a pretty rough operator,and no I don't believe you have a lemon.You really should know the machines limitations. Ain't hatin',just sayin'.

If the 3PT arms have been rubbing that bad from the get go, shouldn't that problem have been addressed 160 hours ago.
Sorry if I sound harsh,but that's the way I see it.

Greg

 

[Wacky]

Hmmm, what happened to the OP.

 

[RoyJackson]

Why do you say that, Roy? Can you site a source?

Actually, it's conjecture on my part...knowing manufacturers build to a cost. Cast iron is pretty cheap, comparatively speaking.

I worked at a foundry a couple years ago...all aluminum, BTW. Aluminum castings aren't particularly cheap, but quite cost effective in low volumes. Also very machinable (depending on the alloy). They're also quite strong, if properly designed (Navy uses a bunch of them) which is why I'm not overly worried about the aluminum castings on my 4400. Must admit though, I would prefer cast iron.

Since cast steel was brought up...that's normally used in high stress situations (rail car couplers, for example). Not cheap, but very tough and long lasting.

 

[PCABE5]

One question, if the rears reduction gearboxes were replace twice before why didn't JD replace those 3pt arms under warranty after the first and/or second break? Known problem.

Being that it was in 4wd I see no evidence in the attached photos that he was spinning the tires. But if he did spin and it grabbed something it might break but I doubt very much that this was the case with an open axle setup. Or are we assuming he had it in 4wd and the rear diff lock engaged.

IMO, he would have had to be in reverse in order for the 3pt arm to have broken the axle. Based on tread design, going forward the tread would rub and in reverse the tire could try to climb the arm if it grabbed it right. Going up the 3pt arm something will give, tire, arm or axle.

Also IMO when in 4wd the front drive shaft is the weakest link rather than the reduction gear boxes.

 

[JDdude]

I never liked the looks of this planetary drive myself..But I just ordered a 2520 today because of the screaming deal I got..They gave me retail for my trade and wholesale on their 2520..

My farmer buddies told me that all of the combines use this kind of drive system and that I will never have any issues for the way I plan on using this tractor..I agree..So I ordered it..

 

[slowzuki]

Its not planetary, its a spur gear design. Was popular years ago (50+) until one brand became known for theirs breaking frequently in their tractors and bulldozers. Just now it seems to be coming back.

 

[jonyyuma]

Did you ever stop to think, of what it would cost to make Forged steel items and associated machining costs? Think tractor parts are high now???Example: Crankshafts for certain types of engines..Wow....I worked in IH foundry for a short spell, they poured cast iron and Malleable parts for many Mfrs. at that spot.White iron and cast was the softest type.Aluminum is much simpler to work with and machine, plus the processing is much easier and fool-proof.Hence, many parts of your machine are cast poured and need to be treated with respect.

 

[JDdude]

Its not planetary, its a spur gear design. Was popular years ago (50+) until one brand became known for theirs breaking frequently in their tractors and bulldozers. Just now it seems to be coming back.

I just call it that kind..I know it is gears and not the 3 gear in a gear deal..I will find out if it holds up I guess..done deal for me..

 

[PapaPerk]

I just call it that kind..I know it is gears and not the 3 gear in a gear deal..I will find out if it holds up I guess..done deal for me..

LOL! That's like calling an apple a pear. Both are fruit... but that's about it! LOL

Plantentaries are very rugged. A spur gear set-up... not so much.