Tires Worry about tires

[Anonymous Poster]

Although the addition of weight to the rear of the tractor (via weights, ballast or an accessory) will help to stabalize the tractor, it will increase the effective load on the front tires, thereby making the flattening problem worse. This effect will diminish, once sufficient rear weight has been added to the point where the rear no longer lifts. (Think about it; As weight is added at the rear to bring it down, that weight is being bore by the fulcrum point, i.e. your front tires.) So, as noted by others, first check your air pressure, if that's not the problem, you're overloading the tires' design capability. If that's the case, it's time to start thinking about new tires.

 

[MChalkley]

What part of WV is Princeton in? I live in eastern VA (a long ways from WV) but get over into the western part fairly often.

Mark

 

[Djwalker]

I agree with the comments about counterweights. Also, you need to increase your front tire pressure for heavy loader work. Kubota recommends up to 30-35 psi. I typically use about 30 psi all the time in front since I use my loader alot. You'll never squish the tires flat with that pressure.

Dave

 

[Bird]

Princeton is in the very southern tip; straight north up I-77 above Wytheville, VA.

Bird

 

[W5FL]

NO NO NO - Adding weight to the rear will NOT increase the weight on the front tires! (unless the tractor was already standing on it's nose)

A tractor needs to be set up properly to use a loader at anywhere near the load limit capabilities specified by the manufacturer. Get all the weight you can on the rear wheels. Wheel weights or ballast in the tires. This ADDS significantly to the stability of the tractor. You still need weight on the three point hitch. Kubota recommends a rear implement such as a box blade weighing 850# on my tractor and I have 1200# water/antifreeze (non toxic) in the rear tires.

If you consider the rear axle fixed (and that is a pretty good assumption if I am going to be on the tractor), the weight in the bucket is transferred almost entirely to the front tires with no counterweight on the tractor. In this case the front tires need to be rated to take the weight on the front of the tractor plus the weight in the bucket (assuming the tractor frame is rigid). A counterweight relieves part of this load. The distance to the counter weight (implement on the rear) is approximately 5 ft and the distance to the bucket from the front axle is approximately 4 ft. 500# on the counterweight balances out 600# on the bucket (unfortunately the sea saw example only works just as the tractor goes nose down and that is not a proper configuration using a loader). The weight on the front tires is significantly less and the additional weight is now on the rear tires and is easily handled by the larger tires.

There is a reason that you have never seen a manufacturer (not a loader company) advertise a loader on a 2WD tractor. The 4WD tractor tires carry a much larger load and have significantly better traction under full bucket conditions.

 

[MChalkley]

See my earlier post on this topic. Adding weight to the rear of the tractor does not increase the weight on the front tires, unless you haven't added enough. As soon as you get enough weight on the back (ballast in the tires is a good start for traction but 3-point hitch weight works better for loader work) that the tires don't come off the ground (and if you don't have at least this much weight, you should lower the bucket to the ground and either walk away or get more weight), every additional pound in the back decreases the load on the front tires.

Maybe that's what you were saying, but it didn't come across that way to me.

 

[W5FL]

Mark, I was actually replying to the post by zfrk01.

Stability of a tractor is defined by me as having all four tires planted firmly on the ground (and no change of winding up on two or less of them). /w3tcompact/icons/smile.gif

A ballast weight (on the three point) absolutely subtracts from the weight on the front tires when using a loader by transferring more than the ballast weight to the rear wheels which decreases the load on the front wheels. When the load is picked up by the bucket considerably more than 100% of the bucket weight is applied to the front wheels due to the bucket load being in front of the front axle. Since more than 100% of the weight in the bucket is always going to be applied to the front wheels, the function of the ballast weight is to both lighten the weight on the front wheels AND to transfer that weight to the rear wheels to keep them firmly on the ground.

More weight in or on the rear wheels increases the stability of the tractor AND make it possible to pick up larger loads than would be possibe with ballast weight alone. My Kubota loader manual says both may not be required "When mounting a heavy rear implement, liquid in the tire MAY not be required." The John Deere manual says you have to have both to get the full rated capabity from the loader.

The bottom line is that front tractor tires have to support a lot of weight when using a front end loader at or near capacity and most tractors are not capable of lifting the breakout weight of the loader without adding considerable additional weight to the tractor.

 

[MChalkley]

Wen, so was I. /w3tcompact/icons/smile.gif

 

[Daniel]

alan l, on my 2710 the rear tires are filled with cal.cloride and I use box blade for counterbalance. sure would not mind some wheel weights too at times. just this week alone, while on vacation, have put 30 hours on it of strictly stump removal work. use bucket for smaller stumps and chains off bucket for large ones. at 40 hours had swaped the turfs for R-4's via my dealer. much,much better for the loader work. stiffer tires plus no punctures as before with the front turfs. rear ballast is extremely important with this type of work. safety first!

 

[Anonymous Poster]

In fact, if the rear tires are lifting off the ground, adding rear weight will indeed increase loading at the front tires. I would draw a vector diagram but we don't have the capability here. A simple analogy would be to picture a simple equal-length fulcrum beam with 10lbs on one side and 8lbs on the other. In this configuration, the 10lb side will go down (of course). At this point, there is 16LBS down force at the fulcrum point(assuming a zero mass fulcrum). Slowly adding weight to the 8lb side will eventually return the system to equilibrum (i.e both sides floating). Now, the fulcrum loading is 20lbs (2lbs more than the balanced condition). In that the tractor's front tires serve as the fulcrum point, the analogy is the same. Physics doesn't differentiate between the two!