Ballast Kubota M7040 front tire ballast

[fleminj2pa]

I recently purchased the tractor pictured below and in order to comfortably handle the 3 pt no-till drill also shown, we had to add approximately 800 lbs. of suitcase weights and brackets along with 400 lbs. of liquid ballast to the front tires only. Prior to adding the weight, attaching to and lifting the drill would bring the front tires up 8-10" on level ground. We first added the suitcase weights and that helped substantially but even then two men could stand on the back of the drill and bounce the front tires. So, we added 20 gal. of rim guard to each front tire and that solved the problem. I used the drill to plant 8 acres of food plot forage on 1.25 miles of gas line in mountainous terrain the very next day and I had absolutely no problems.

However, it's been suggested on another thread that adding liquid ballast to the fronts on the M7040 could lead to problems with the steering, further on down the road. As a tire dealer, we have been ballasting tires for many years and we have never encountered such a problem but I was curious to learn if anyone else had experienced any issues in this regard?

 

[texasjohn]

I've only heard of people having problems with a FEL heavily loaded with low air pressure in front tires and rolling tires off of the rim. Most smaller tractors have small front tires which, if loaded, leaves little air for cushion and reserve in case of a small leak. A larger tire such as you have can hold enough weight to make a small difference, as you report. Smaller tires are not able to hold enough weight to make any real ballast difference.

I know that my Kubota manual says to not put ballast into the front tires. I don't know what yours says. I always carry max tire sir pressure in my front tires because of my heavy FEL loads. Never rolled tires off of rim, but under load the tire certainly squats a lot.

 

[RedNeckRacin]

Does kubota sell a larger front weight bracket? I think JD has two different size ones starting around that size of machine? If your not running a loader and the 3pt will pick up the weight, I don't see any harm in loading the tires. That tractor will never notice the weight difference.

 

[Dave M7040]

The M7040 owner's manual says not to ballast front tires due to effect on steering.
I think a lot of people consider weight in the tires to be the same as weight on a front rack or FEL but they are forgetting the greatly increased gyroscopic forces that come from the extra weight rotating within the tires.
Dave M7040

 

[fleminj2pa]

The M7040 owner's manual says not to ballast front tires due to effect on steering.
I think a lot of people consider weight in the tires to be the same as weight on a front rack or FEL but they are forgetting the greatly increased gyroscopic forces that come from the extra weight rotating within the tires.
Dave M7040

I saw this in the manual and I hear what you're saying but I'm still trying to get my head wrapped around that concept. I'll go back to the issue of inadequate fill level and the associated sloshing that goes with that. We put in 20 gal. of rim guard in each tire, which is all you can get in and still allow room for air pressure. That fills them about to the level of the valve at top dead center. I was watching for any indication of wheel hop or irregular characteristics while operating the tractor the next day and it was smooth as could be...even while operating on the blacktop road at 15 mph.

I think it's interesting that the dealer never once cautioned against adding rim guard. In fact, we discussed it with the setup technician and his only comment was to either fill the rears to the same relative level or leave them unballasted entirely...the issue being trailering weight constraints.

The fact is, as a tire dealer who services ag tires, we've been ballasting tires for years and we routinely fill fronts if requested to do so and to the best of my knowledge there have been no related issues reported, thus far. I'm hoping to hear from someone who has had their front tires filled for some time, with or without related problems.

 

[TomSeller]

That is one downside to taller front tires. The gyro forces are much greater because of the larger radius.

 

[Dave M7040]

Please try this simple experiment. Get the front tire off a bicycle and hold both ends of the axle. Sit in a swivel chair. Have someone spin the tire/wheel as fast as they can. Now try to turn the front wheel like you are steering it. You will find that the swivel chair will rotate and you will be aware of a strong force through your hands.
The heavier and faster the wheel spins the greater the force effect you will experience.
Loading the rotating front wheel with rimguard increases the rotating weight and thus the forces that resist the steering. Gyro's, which is what your front wheel wheel is, want to remain unmoved i.e. don't want to be turned to either side which is why they are incorporated into compasses in airplanes, missiles and ships. The power steering can overcome these forces but only to a limited level and then it will not be strong enough and you will not be able to turn.
Dave m7040

 

[RedNeckRacin]

I think you guys are being overly cautious. The manufacturer is looking out for the general users of the tractors and not specific instances. People have hacked tractors to pieces and once they are out of warranty, its your choice. If the tractor has enough grunt to pick up the seeder and not enough weight to keep it on the ground after adding the max front weights, what options do you really have? If you had a loader, I'd say go find a pile of damp clay and see if that would keep things down but since there isn't one, I don't think that's an option.

 

[skyhook]

Please try this simple experiment. Get the front tire off a bicycle and hold both ends of the axle. Sit in a swivel chair. Have someone spin the tire/wheel as fast as they can. Now try to turn the front wheel like you are steering it. You will find that the swivel chair will rotate and you will be aware of a strong force through your hands.
The heavier and faster the wheel spins the greater the force effect you will experience.
Loading the rotating front wheel with rimguard increases the rotating weight and thus the forces that resist the steering. Gyro's, which is what your front wheel wheel is, want to remain unmoved i.e. don't want to be turned to either side which is why they are incorporated into compasses in airplanes, missiles and ships. The power steering can overcome these forces but only to a limited level and then it will not be strong enough and you will not be able to turn.
Dave m7040

Good point, but I wonder if it would apply to a 16" tractor tire,
remember, these don't turn as fast.

 

[Dave M7040]

Why do you think Kubota puts the caution in their owners' manuals?
Dave M7040

 

[fleminj2pa]

Why do you think Kubota puts the caution in their owners' manuals?
Dave M7040

I don't know why they put it in there but I'm going to find out. What I do know is that in this day and age, a lot of disclaimers are put out by manufacturers because some hack lawyer somewhere sued them over something idiotic and won. In many cases, they don't have to thing to do with common sense or practical application. Why can't you buy a decent gasoline can these days? Same reason....

"The heavier and faster the wheel spins the greater the force effect you will experience..." Top speed on this tractor in high/high is 18.4 MPH...I ran it at 15 mph with absolutely no evidence of any of these theoretical problems. Maybe those next 3.4 mph would make a difference but I doubt it. However, I don't know that for sure so I'm going to keep researching this until I do.

 

[TomSeller]

What I do know is that in this day and age, a lot of disclaimers are put out by manufacturers because some hack lawyer somewhere sued them over something idiotic and won..

What if Kubota did not put that clause in there and someone was transporting their tractor with front tires filled at 18.4 mph around a curve and lost control because it overcame the power steering and slammed into a school bus full of TBN member's kids killing or maiming them all? I bet these "hack" lawyers would be getting lots of calls from TBN members intending legal action against Kubota because they filled the front tires without it being recommended claiming "it didn't say not to". People like to say these lawsuits are frivolous but when they themselves stand to benefit, they lawyer up almost every time.

I prefer to use tools within the manufacture's recommendations.

 

[fleminj2pa]

What if Kubota did not put that clause in there and someone was transporting their tractor with front tires filled at 18.4 mph around a curve and lost control because it overcame the power steering and slammed into a school bus full of TBN member's kids killing or maiming them all? I bet these "hack" lawyers would be getting lots of calls from TBN members.

What I'm looking for...who I'm looking for, is someone who actually filled their tires and as a result lost control. Hypothetical theory notwithstanding, we've been in the tractor tire business since 1955 and have filled thousands of tires over the years. Not once have we ever had any customer come back to us and describe any of these conditions or symptoms. I'll tell you what has happened...on ocassion someone has talked one of our techs into short filling a tire below the 85% full recommendation because they didn't want to pay for a full, proper fill and then they took it out and ran it down the road at top speed and the tractor took to hopping like a jackrabbit. There's your "sloshing" effect for you. As far as gyroscopic effect...we're not talking about a Mazeratti here, we're talking about a tractor that spends most of it's time going 5-10 mph. I ran it at 15 mph and experienced no such symptoms. We can talk about ground speed vs. revolutions per mile or any other abstract theory out there but all I'm interested in hearing about are real world, hands on experiences of a problematic nature. So far, I haven't heard anyone say, "I filled my tires to the valve at top dead center and this is the bad thing that happened to me."

As far as Kubota is concerned, I plan to see if I can get someone from Kubota to tell me why they put this disclaimer in their Owner's Manual. I doubt that will happen. In the over litigated society we live in today, manufacturers of just about anything are faced with a nightmarish world of "what if's"...what if some stupid *** takes our product and does this brain dead thing? Well, OK, I guess we better put a disclaimer on it to cover our butts. I'll be sure to report back if I learn anything of a real and significant nature...and I'll be extra careful to avoid schoolbuses.

 

[bruceatlam]

"I'll be sure to report back if I learn anything of a real and significant nature...and I'll be extra careful to avoid schoolbuses."

Particularly those full of TBN members kids --------------- !!!!!!!!!!

 

[fleminj2pa]

Once again, if anyone has a real world, first hand experience to share that would shed light on this issue, I'm all ears. I don't want to be rude, but the rest of this conjecture, theory and abstract BS is a useless waste of time. I'm afraid I see this discusson turning ridiculous when it starts to go to killing and maiming a schoolbus full of kids...TBN member kids or otherwise. Next, we'll be discussing the political ramifications of liquid ballast in front tractor tires. Geez!

 

[FTG-05]

I have the same warning in my Kubota owner's manual and I filled my front tires with RV AF and WW fluid. I've see no ill effects or apparent loss of control or steering or both. I haven't tried to run any races with my tractor but I do run it down one mile gravel road when moving recycled concrete and I've seen no problems with front loaded tires.

Good luck!

 

[big bubba]

so is it safety liability or potential mechanical failure? i'm all ears...don't know myself... should have gone beyond physics 101 yrs ago...

 

[whis]

As long as you are moving when turning I don't see a problem, no different than something real heavy in front bucket

 

[TomSeller]

I think you would have to be turning while at high speed which most people don't do on a tractor.

 

[big bubba]

I think you would have to be turning while at high speed which most people don't do on a tractor.

would agree with you on that (in terms of safety) good pt. mechanical? not sure