You need balast or you will trash your front axle!!!! really?

[gladehound]

Im not sure you actually said it, but wrong would be any implication that counterweight would spare the front axle if you were really using a TL anywhere near its limit. If babying it; like just carrying stuf around in the bucket, you could find counterweight that would lessen the load on the front axle under specific circumstance, but those weights are trivial compared to the front weights you will encounter with those same counterweights in push/lift scenarios.

,,,,,I cannot believe there was ever any doubt that weight behind the rear axle lightens the front under static/light/predictable conditions. [Incredulous Icon]

Thanks more making sure we all get it even though nobody said anything to the contrary. :laughing: This thread has become more fun than I ever imagined it would

 

[gladehound]

Few things that need to be mentioned here:

1: Gladehound (plus any others that might be in this thinking) Having loaded tires while very useful for adding weight/traction that then means you can carry/lift more with the loader DOES mean that when you carry/lift more you are also subjecting your front axle to more weight/stress thereby potentially increasing the chances of axle failure sooner. Why is this so? Look at that great diagram posted earlier (Koua just posted it again post number 94) by adding weight to the rear tires you're only effecting the front fulcrum which allows the tractor to lift more without the rear end coming off the ground. (Potentially if you can get enough weight into your tires you could max the lift capacity of the loader and still keep the rears on the ground. Sorry I'm too lazy to draw this out but hopefully if you look at that diagram you'll understand.) So if the front axle is the only fulcrum affected then when using the loader it gets the additional weight applied down thru it.

...So that is an additional reason why when using the loader the best place to have additional weight is behind the tractor - a counterweight on the 3pth. I hope this helps as I noted by your posting and your picture that you don't use a real counterweight that's hung behind the tractor far enough to be of much effect.
You're asking about damage or potential damage to the front axle - yes you're making your tractor useful by weighting your tires but you're not helping your front axle. use a counterweight and you'll both make your tractor useful and add to the longevity of your front axle.

...now I had a couple other points but I forgot what those were. lol! Till next time if I remember.

E.

I agree with your post. No explanation needed for my sake. I am not and never was among those "in this thinking" (if there are actually any in that thinking).

However, for my uses, there is a lot of down side to a 3pt counterweight. It decreases maneuverability, impacts steering, decreases bucket down force for digging, and decreasing ability to push snow in float mode without the front coming off the ground.

Not using a 3pt weight is a trade off. And as you realize, I could add even more weight to the front end in a dynamic situation using a 3pt weight in addition to what I already have for ballast and indeed I have done just that! I once picked the whole rear off the ground with my 8 foot blade on the 3pt while trying to remove a stump. Not one wheel, both! This happened because I was maxing out my lift while backing up. Probably had about 10,000 pounds on the front axle at that moment.

This discussion has been good as it has gotten me to think more about babying my front axle, and there may have been a few who learned something about how these forces work in static or dynamic situations.

I'll probably take my ~500 pound bucket off when not using it just to slow the wear rate on my front axle. As far as my front axle is concerned, that's about the equivalent to adding a 2,000 pound weight box to the 3pt hitch.

 

[AxleHub]

If you still think movement is required, or that 4570's example showed movement or proved movement, then you're still not getting it and you're still wrong (or unable to admit you're wrong). I vote we move on and stop the nonsense. You derail way too many threads with these types of tangents.

It's OK to be wrong -- I am wrong all the time. But it's important to recognize when you're wrong and/or when others are right. I think that's maybe more important than being right in the first place.

I'm not sure why you think I didn't admit I was incorrect. I believed ground contact was a constant when it actually is a variable because ground pressure changes. And because of that I could not see movement of the lever happening. You claim movement isn't required.

But if I put 500 pounds on my scut 3pt hitch . . . With no other changes . . .I'll guarantee you that the lift pins are closer to the concrete slab than they were before the 500 pounds was added. Whether caused by tires squatting or front axle/tires less squatting . . Movement occurred . . Downward in back and upward in front.

4570's 2nd example showed me I was missing something . . Ground pressure changes not simple ground contact. But s219 you seem to be missing something also . . the fact that adding more weight creates a shift in the lever . . A movement. Can you deny there is not a measurable movement closer to the concrete when 500 pounds is added to a scut 3pt lift arms ? Or that ground pressure is not increased at the rear axle and decreased at the front axle?

But 4570's example is a "2 for 1" effort . . because not only did It demonstrate my original error . . but it also proved Glade's original point in his first post which is that on the short side of the lever it takes a huge weight change to makeba far smaller difference to the long leg of the lever (front axle).

Are you debating I didn't recognize my error when I stated it twice in the same post?

Or are you debating movement didn't take place as in my example in this post sbove?

Or that ground pressure didn't increase to the rear axle and decrease to the front axle as in my example in this post?

Or that glade was incorrect in his observation in his initial thread opening post?

Seems to me they all tie together . . but maybe I'm incorrect again. I'm certainly willing to listen.

 

[gladehound]

...Can you deny there is not a measurable movement closer to the concrete when 500 pounds is added to a scut 3pt lift arms ?....

Hi Axle. You are absolutely correct in your observation that the tires squat in the back and lift in the front when you add a big counterweight to the 3pt hitch.

However, even if you had uncompressible tires and every component of your tractor was completely ridged so that no geometry changed when you added weight to the 3pt, the results of adding counterweight to the hitch would be the same.

(sure, someone could dispute the affects of the geometry changes caused by the tire squat both those differences are so small that it's really not worth the conversation and it will just confuse a bunch of people)

If someone wants to take the time to demonstrate that the squat of the tires has little to no impact they could do the weight experiment with a model with pneumatic tires at low pressure and do the same experiment with something with steel wheels. Someone else can probably explain it better then I. I'm more of a doer than a teacher.

 

[AxleHub]

Glade, its my understanding that if the tires didn't squat and there was no "give" in the luft arms ir frame . . that ground pressure would rise on the rear axle and reduce on thw front axle and that would cause the fel to lift some and the 3pt hitch pins to lower some . . Creating a smaller movement than if each side of the lever was the same length. Thus it supports your initial concept that with a very short distance of rear axle to 3pt lift arm pins and a very long distance from rear axle to fel front . . it takes a big difference in rear ballast for a smaller change in in front axle pressure. I also assume the tip of the fel bucket front edge moves upward more than does the 3 pt. Pins move downward in measurement

 

[RedNeckRacin]

WE also need to differentiate between simply adding ballast and adding counter weight. Adding weight at the rear axle does increase the possibility of adding more weight on the front axle up to the point of the rear tires lifting or the hydraulic relief maxing out and the loader failing to lift more weight. HOWEVER, Adding counter weight (maybe this is more clear a name than simply saying ballast) behind the rear axle would also increase lifting capacity until the loader stalls out but you can add more counterweight to again take weight off the front axle after the loader fails to lift anymore weight due to the hydraulic restrictions.

Someone has referenced this vaguely in an earlier post but I don't remember exactly who said it after all these posts.

 

[gladehound]

WE also need to differentiate between simply adding ballast and adding counter weight. Adding weight at the rear axle does increase the possibility of adding more weight on the front axle up to the point of the rear tires lifting or the hydraulic relief maxing out and the loader failing to lift more weight. HOWEVER, Adding counter weight (maybe this is more clear a name than simply saying ballast) behind the rear axle would also increase lifting capacity until the loader stalls out but you can add more counterweight to again take weight off the front axle after the loader fails to lift anymore weight due to the hydraulic restrictions.

Someone has referenced this vaguely in an earlier post but I don't remember exactly who said it after all these posts.

Agreed. And nicely / simply stated.

 

[dirt ditch]

Several years ago John Deere had a downloadable Compact Utility Tractor Ballast Calculator excel spread sheet on their website. It gives front and rear axle weights with different attachments and loaders. The following calculations are of a John Deere 3320 using the spread sheet.

JD 3320 only. 42% front / 58% rear
View attachment 458223

JD 3320 with only 880 pound rear ballast box. 21% front / 79% rear
View attachment 458224

JD 3320 with only 300CX loader. 57% front / 43% rear
View attachment 458225

JD 3320 with 300CX loader & 880 pound ballast box. 36% front / 64% rear
View attachment 458226

 

[GolfAddict]

Several years ago John Deere had a downloadable Compact Utility Tractor Ballast Calculator excel spread sheet on their website. It gives front and rear axle weights with different attachments and loaders. The following calculations are of a John Deere 3320 using the spread sheet.

JD 3320 only. 42% front / 58% rear
View attachment 458223

JD 3320 with only 880 pound rear ballast box. 21% front / 79% rear
View attachment 458224

JD 3320 with only 300CX loader. 57% front / 43% rear
View attachment 458225

JD 3320 with 300CX loader & 880 pound ballast box. 36% front / 64% rear
View attachment 458226

Wow, it is more significant than I would have thought!

Of course, it's only because the rear tires squatted so much.

 

[LD1]

Rear ballast certainly takes weight off the front axle. But do you admit rear ballast also adds weight to the front axle (defined by: it enables you to load the front axle to much more than it would otherwise see)? Which gets us back to the OP's original post.
I think it's hard for people to wrap their head around (or communicate) this contradiction.

3pt balast takes some weight off the front axle when unloaded/lightly loaded....
BUT...
The added lift capacity that ballast gives the loader will likely result in a higher cumulative stress on the front axle as heavy loads can be regularly placed on the loader!

YEs, I understand, and is the same thing I repeat in about every one of these ballast threads come up.

I usually word it something like the followning:

Not only do you need enough ballast to keep the rear down, but you need enough to actually take weight off the front.

Adding ballast increases the load the front can have, up to the point of just enough ballast to keep the rear end down. THAT is the max the front will see. From that point forward, any additional counterweight works to unload the tractor.

Rough example.....3000# tractor with no weight might be able to lift 500# in the FEL then the rears lift....that puts 3500# on the front axle.

Add 500# counterweight and you might now be able to lift 1000# in the FEL before the rears lift. Now the 3000# tractor + 1000# load + 500# ballast = 4500# all on the front axle.

Add a 750# ballast allows you to "just" max out the loader at 1250# and rear tires just on the verge of lifting, so now 3000# + 1250# + 750# = 5000# on the front axle.

Continuing to add ballast from here isnt going to increase lift capacity any further. So lots put a 1500# weight on, 1250# FEL load. The extra 750# works to unload some weight off the tractor. Lets say its countering effect is 500#. So now you have 500# + 1500# = 2000# over the rear, and 3000+ 1250 - 500 counter effect = 3750# over the front.

I usually give some example like that. While unsafe, having no ballast or nothing in the tires is NOT going to overload the front axle. Just not enough tractor weight and lift capacity. If you use counterweight, use enough of it.

 

[npalen]

I'm getting a headache!

 

[LD1]

I'm not sure why you think I didn't admit I was incorrect.

Are you debating I didn't recognize my error when I stated it twice in the same post?

Because after about 4 posts you still DIDNT admit that you were incorrect or wrong. You simply answered "yes I understand" to my question. And continued to ramble about why you thinking the way you were (incorrectly), and made some long winded references as to what/how you have learned.

Like I said, A simple "yea, I understand now" or "I was wrong guys, thinks for straightening me out" would have been sufficient.

Glade, its my understanding that if the tires didn't squat and there was no "give" in the luft arms ir frame . . that ground pressure would rise on the rear axle and reduce on thw front axle and that would cause the fel to lift some and the 3pt hitch pins to lower some . . Creating a smaller movement than if each side of the lever was the same length. Thus it supports your initial concept that with a very short distance of rear axle to 3pt lift arm pins and a very long distance from rear axle to fel front . . it takes a big difference in rear ballast for a smaller change in in front axle pressure. I also assume the tip of the fel bucket front edge moves upward more than does the 3 pt. Pins move downward in measurement

It doesnt have to be rubber tires with squat. IT could have solid steel wheels that dont move a but and the principal of weight transfer still applies.

You load up one end with weight that is beyond the pivot point (axle) weight tranfers because you have created a lever, not because tires squat a little.

 

[Luke'sScreenName]

This may need to be refined but...

View attachment 458196

What? Doesn't everyone love graphs as much as I do? :confused3:

 

[ovrszd]

I'm getting a headache!

Me too.

Since my name has been mentioned several times I would love to jump into this fray. But I'm still trying to rebound from being called the dumbest human on this planet yesterday by Coyote Machine. So I'll just crawl back into my cave......

For my beliefs, see post #76 on page #8 made by Spyderlink.

 

[jenkinsph]

Very entertaining thread.

 

[CalG]

The simple reality: (well, not really simple ;-)

The entire mass of the tractor and any load, ballast and counter weight will be divided between front and rear axles, in some proportion between 0 and 100 %, and summing to 100%.

Any mass added to the tractor in front of the front axle will add load to the front axle in magnitude proportional to it's position and will include the weight transferred OFF the rear axle. And vice versa at the rear axle. The bucket of a FEL is a typical example of the former.

Any mass added to the tractor behind the front axle as far as the rear axle, will act to INCREASE the load carrying capacity of a FEL insofar as NOT lifting the rear wheels off the ground by loads attached ahead of the front axle is the concerned. Such added weight can be termed "BALLAST". This includes adding ballast to the tires etc. The total load carried by both axles will be INCREASED for all loadings of a FEL over the same conditions without the added weight. Note Well, That adding ballast to tires can only INCREASE any strain on the front axle due to loads in the FEL, or other front mounted equipment.

Any MASS added behind the plane of the rear axle will act to counter the weight or force carried on the front axle. This additional mass may be termed "counter balance", and includes 3pt implements, carry-alls and dedicated weight boxes etc. Such weight will add to the load carried on the rear axle by both the mass of the counterbalance AND the weight transferred off the front axle.
Simply, weight added behind the rear axle counter balances weight ahead of the rear axle. The front axle must be considered on it's own!

But don't forget:

All the weight carried by the tractor will be shared between the front and rear axles. (There truly is NO FREE LUNCH!)
If there is sufficient weight, mass, inertia, or momentum to tip the system about either axle, the entire load will be carried by the other axle. Wheelie due to sudden start off, high pull load, sudden STOP, even a bump or dip.

The "static" condition assumes an "acceleration" of one gravity. The dynamic situation, that is moving loads could easily approach 4-5 times that acceleration. (bump or dip) And thus the apparent load on either axle.

The extreme case of static loading the front axle with the combined weight of tractor, load, ballast and counter balance could be limited through hydraulic relief to some degree,(think break out force) but the dynamic loading will remain uncontrolled. So no guarantee there.

Finally, There is a thread on the forum elsewhere of a front axle failure without a fully understood cause. The poster described conditions of carrying loaded buckets of gravel in the FEL.
My sentiment would be that if sufficient counter balance were being carried to result in a front axle loading equal to an empty bucket, the failure would have been prevented . Of course I have no idea how rapidly the material transfer operation was being conducted, and can not know the G loads experienced.

Same as others, just different words. And most of it can be understood while the tractor is just standing in the yard. Even if the dynamic condition is likely the straw that breaks the camel's back. (So that 10% margin of the original post now becomes 50% due to inertia loads from things carried in the bucket.)

Oh well, stuff breaks...;-)

 

[4570Man]

What difference does tire squat make? I could remove the counter weight from my forklift ( way too much trouble since it weighs a couple of ton ) and pick up a 1 ton load on the forks. It should be able to lift this load without a counterweight and then weigh the front axel. Now I put the counterweight back on, lift the same 1 ton load and weigh the front axel again. At which test is there going to be less weight on the front axel? The forklift has small solid tires so tire squat will be extremely minimal.

 

[CalG]

What difference does tire squat make? I could remove the counter weight from my forklift ( way too much trouble since it weighs a couple of ton ) and pick up a 1 ton load on the forks. It should be able to lift this load without a counterweight and then weigh the front axel. Now I put the counterweight back on, lift the same 1 ton load and weigh the front axel again. At which test is there going to be less weight on the front axel? The forklift has small solid tires so tire squat will be extremely minimal.

Squat means "squat". ahh, err... nothing to this conversation....;-)

regarding your forklift, it's likely that adding the counterweight takes some load off the front axle and adds to the rear axle load.

 

[4570Man]

Squat means "squat". ahh, err... nothing to this conversation....;-) regarding your forklift, it's likely that adding the counterweight takes some load off the front axle and adds to the rear axle load.

It certainly does, but the counter weight is factory. In this situation the counter weight would make very little difference to the front axle since it rides very close to the rear axle. With no load on forks the rear axle is carrying nearly double what the front axle is. According to the chart on the side there is still 2,600 pounds on the rear axle with rated capacity on the forks and 15,000 pounds on the front axel with rated capacity on the forks. Now that how much that is when those solid wheels hit a bump.

 

[Snowback]

I think the key to making sure you don't trash your front axle is to use THIS much counter balance...