Unvenferth Spacers on a JD3730?

[vtsnowedin]

Backhoes are heavy... I couldn't find the weight specs for the 485 or 475 hoes but the 448 with a 24" bucket ranges from 1420lbs to 1460lbs depending upon the frame size of the mount - 3000 or 4000 series tractor.

The 447 hoe is 1,035lbs.

Now, if you use the JD ballast box with the Quick hitch and fill it with Portland cement you'll have 1,079lbs. hanging off the 3pt.

Or, if you'd like a bit more ballast and go with the ballast box extension - it'll be another 316lbs heavier - at 1,395lbs.

Backhoes are heavy - but, not dramatically more than a tried and true; ballast box!

AKfish

Yes of course but that was not what I was trying to get across.
My point is that every option you choose can add or remove load from the components of the tractor. If you add together axle extensions with a backhoe and hard usage these all add stress to the bearings and the castings that hold them. By themselves each is no problem or not much of one but they tend to multiply together not just add up and the result of that multiplication can approach the yield point of the bearings or the casting. Throw in the wild card of a lightweight aluminum casting and you might have a problem.

 

[greg_g]

The R4 rims are a 2-position rim. There is an "offset" change in position between the axle hub and the outside of the rim/tire.

The operative words in my post were "no meaningful offset". Inch and a half at best, and causes aggravation by moving the valve stem inside the rim. It's unnecessary work when you're in a hurry, to have to move the tractor 4 times just to get at all 4 valve stems.

....The accepted manner to operate a tractor backhoe -- at least by the training recommendations of the International Union of Operating Engineers --

does not include the aluminum rear ends on JD 2x20 and 3x20 series compact utility tractors. Please keep your apples out of our oranges.

//greg//

 

[greg_g]

Backhoes are heavy... I couldn't find the weight specs for the 485 or 475 hoes but the 448 with a 24" bucket ranges from 1420lbs to 1460lbs depending upon the frame size of the mount - 3000 or 4000 series tractor.

Please exclude 110TLB and 4x20 series (and larger) from the discussion. I don't have a clue why you can't accept the fact that we're talking about stresses on the aluminum rear ends on the 2x20 and 3x20 series only. John Deere willingly takes your money to install spacers on the cast iron 4x20 (and larger) series, but refuse to do so on the smaller aluminum CUTs.

//greg//

 

[AKfish]

Please exclude 110TLB and 4x20 series (and larger) from the discussion. I don't have a clue why you can't accept the fact that we're talking about stresses on the aluminum rear ends on the 2x20 and 3x20 series only. John Deere willingly takes your money to install spacers on the cast iron 4x20 (and larger) series, but refuse to do so on the smaller aluminum CUTs.

//greg//

The ballast box that I noted is the ballast box that is available for the 2000, 3000 and 4000 series machines.

There's only ONE model available from Deere... Maybe you can COMPREHEND that!

Many of the spacers that have been utilized by other's here on TBN are ONLY 2" extensions. That is EXACTLY the width of the SS extensions that I and other's have employed. Some have doubled them together for a total of 4".

So, 2 inches is all that is necessary for many uses.

John Deere will NOT take your money for any wheel extensions for 2000, 3000 OR 4000 machines - period! They do not offer them.

5000 series and greater...

My point -- and I believe that you made a similar distinction as well -- is "why would Deere offer a backhoe and/or a ballast box configuration that heavy if they had design concerns regarding the longevity of the tractor's rear transaxle"? The same question can be asked regarding the discussion of R1's versus R4's.

So... for user's of 2000 and 3000 machines that are concerned about "excessive loading" of the tractor's rear axles -- don't buy R1's and extend the rims out if you're going to use a ballast box... and most definitely DO NOT buy a backhoe!

Really...

Much ado about nothing -- IMHO.

AKfish

 

[hanson1999]

thanks akfish.... some people huh....

 

[greg_g]

John Deere will NOT take your money for any wheel extensions for 2000, 3000 OR 4000 machines - period! They do not offer them. 5000 series and greater...

Sorry, I can only be accurate as the dealers I've dealt work with. Where I bought my 3720, I was told clearly that they sell & install spacers for 4x20 and up. Matter of fact, I believe they even mentioned they were Unvenferth.

But I don't know where you got the idea that I'd have any argument with the JD ballast box, with or without reasonable spacers. And by reasonable, I mean spacers that don't widen the track beyond 68". The JD box is designed primarily as a counterweight to a full bucket up front, with a secondary benefit of increased rear traction. It only extends a foot behind the lift arms, has no moving parts to exert potentially damaging force on the axle housings, and - even when fitted with the extensions - weighs considerably less than say a JD485 backhoe. Matter of fact, I've got several three point implements that weigh quite a bit more than my ballast box. The backhoe and the ballast box represent two completely different sets of geometric force relative to the 2x20 and 3x20 rear axle housings.

//greg//

 

[AKfish]

But I don't know where you got the idea that I'd have any argument with the JD ballast box, with or without reasonable spacers. And by reasonable, I mean spacers that don't widen the track beyond 68". The JD box is designed primarily as a counterweight to a full bucket up front, with a secondary benefit of increased rear traction. It only extends a foot behind the lift arms, has no moving parts to exert potentially damaging force on the axle housings, and - even when fitted with the extensions - weighs considerably less than say a JD485 backhoe. Matter of fact, I've got several three point implements that weigh quite a bit more than my ballast box. The backhoe and the ballast box represent two completely different sets of geometric force relative to the 2x20 and 3x20 rear axle housings.

//greg//

Depending upon what type of material is used to fill the ballast box (with or without the extension) it DOES weigh NEARLY AS MUCH AS A JD485 backhoe! Within a 100 lbs! Please reread my previous post.

And, per my post regarding the Operating Engineers manual for correct operational procedures for a tractor-loader-backhoe the backhoe should be operated with all wheels elevated.

Therefore; - NO, NADA, NONE force is exerted upon the axles, bearings or differential of the tractor while using the backhoe. The torsional forces are transferred through the frame of the tractor to the front loader and/or rearward to the stabilizers.

My point - the mounted backhoe is little different than the mounted ballast box - when the tractor is used as a front loader machine or when the tractor is used as a backhoe.

AKfish

 

[Dan Hunter]

Trashing my own thread, I've always operated under the impression that aluminum and steel have the same strength per pound. I don't think JD is building the axle of aluminum to be light or reduce costs but to leverage the advanced in casting. I would think a properly engineered aluminum axle would be no less durable than a steel unit.

 

[greg_g]

Trashing my own thread, I've always operated under the impression that aluminum and steel have the same strength per pound. I don't think JD is building the axle of aluminum to be light or reduce costs but to leverage the advanced in casting. I would think a properly engineered aluminum axle would be no less durable than a steel unit.

Not the axle itself Dan, the weak point is the axle housing. The steel wheel exerts force on the steel axle which rotates through a steel wheel bearing which is pressed into a cast aluminum axle housing.


//greg//

 

[jimgerken]

There is no doubt in my mind that JD uses aluminum rather than steel to save money in casting and machining. We can only HOPE they did the FEA to have confidence the strength is adequate with safety margin. Short of having the data, I guess we could go with experience. For instance, let's go ahead and list every 2000 and 3000 series final drive gearbox that has broken, in our experience or even any one you've heard of. Please give specifics so we don't count one incident more than once. Specific circumstances would also be helpful, such as implement in use at the time, duty performed, speed, temp, spacers or not, etc.
I will start. I know of none, and don't believe I have read of one on this forum in the ten years I have read it. I know a guy who broke off an ear, the part that the 3-point draft arms mount to. JD warranteed it. No oil on the ground. I forgot the circumstances, but the guys user name is Ding2520.
Your turn.
Thanks.