Comparison Looking at buying new tractor, LS vs Kubota

[Mike476]

I though Gary's analysis of the engineering of the drawbar was that is was designed to break before doing any damage to the tractor housing. In other words, repair or replace a fairly inexpensive part before damaging a very expensive part. Sounds like good engineering to me.

James K0UA

From what I've read, that's it in a nut shell. :thumbsup:

 

[SPYDERLK]

No, to all those making an excuse for the tractor drawbar failing. Proper design includes adequacy for function. We are not talking about about a failure due to jerking, but one that happened when the tractor was used to pull as hard as its traction allowed. That is what the drawbar is made to do. When you cant do that it is underdesigned.
larry

 

[houstonscott]

No, to all those making an excuse for the tractor drawbar failing. Proper design includes adequacy for function. We are not talking about about a failure due to jerking, but one that happened when the tractor was used to pull as hard as its traction allowed. That is what the drawbar is made to do. When you cant do that it is underdesigned.
larry

So in your assessment that model is over powered.

HS

 

[SPYDERLK]

nnnooono.

 

[MtnViewRanch]

No, to all those making an excuse for the tractor drawbar failing. Proper design includes adequacy for function. We are not talking about about a failure due to jerking, but one that happened when the tractor was used to pull as hard as its traction allowed. That is what the drawbar is made to do. When you cant do that it is underdesigned.
larry

I agree with Larry, BUT did Gary jerk on the truck to get it out. Pretty tough not to when something is really stuck. My feeling is that the failure was from abuse, not intentional, but from abuse non the less.

Larry, have you looked at the new draw bar system on the newer 7520s (now older) and 8560s. No where as strong as what ours are. They raised the draw bar up to increase ground clearance and by doing that took away a lot of the strength IMO.

A tractor, any tractor should be able to withstand any and all non moving pressure exerted by it's own weight.

 

[SPYDERLK]

BUT did Gary jerk on the truck to get it out. Pretty tough not to when something is really stuck. My feeling is that the failure was from abuse, not intentional, but from abuse non the less.

Larry, have you looked at the new draw bar system on the newer 7520s (now older) and 8560s. No where as strong as what ours are. They raised the draw bar up to increase ground clearance and by doing that took away a lot of the strength IMO.

A tractor, any tractor should be able to withstand any and all non moving pressure exerted by it's own weight.

I too am concerned based on the description of the newer design. I just didnt see a way to do a good fastening higher up - and I figure you lose the important length and perhaps swing adjustments originally provided. They were too low tho.
iiiiiiiI didnt read any abuse into the drawbar failure other than that occurring naturally via traction hop. Some small level of jerking always occurs in a pull, but the difference between that and a running start is huge. The former should comfortably fit within the design margin of the tractor. If it doesnt youre under a burden of always having to work tentatively.
larry

 

[MtnViewRanch]

I too am concerned based on the description of the newer design. I just didnt see a way to do a good fastening higher up - and I figure you lose the important length and perhaps swing adjustments originally provided. They were too low tho.
iiiiiiiI didnt read any abuse into the drawbar failure other than that occurring naturally via traction hop. Some small level of jerking always occurs in a pull, but the difference between that and a running start is huge. The former should comfortably fit within the design margin of the tractor. If it doesnt youre under a burden of always having to work tentatively.
larry

You can only imagine how low mine is with the R4s. I have actually figured a way to raise it up about 3", with little to no strength loss. Just need the time to do it.

As far as the breakage on the LS, I still feel that it was either some sort of unintentional abuse or a faulty part. The LS tractors are pretty beefy machines.

 

[xtn]

A tractor, any tractor should be able to withstand any and all non moving pressure exerted by it's own weight.

I agree. However it should be noted that any decent tractor has the capability - under cooperating conditions - to exert way more force than its own weight.

 

[MtnViewRanch]

I agree. However it should be noted that any decent tractor has the capability - under cooperating conditions - to exert way more force than its own weight.

This is true, but the manufacturer has no way of knowing how severe the operater will push the capacity, so I'm sure that there is a safety factor figured in, but just how far does one go? 2-1, 3-1, 4-1? Momentum can do a lot of damage. In the Nebraska tests, I don't think that you will find any tractor that will dead pull it's own weight. So just how strong does something need to be built? :confused3:

 

[northpolefolks]

Give someone a block of steel and it shouldn't break, but if you drop it off a cliff it will leave a mark on itself.

No tractor in this class is designed to pull against 40K pounds, let alone bounce around when doing it.

The weak point caved and saved alot of money. Too mouch strength there and you start tearing up tires, trannys ect. I will choose the draw bar weak link any day. I highly doubt that "normal" usage includes pulling on loaded dump trucks.

If we were seeing dozens of these failures I would be concerned. But were not.

I was just out at the LS dealer and like he said "if you need a commercial wrecker get one, no mid size utility tractor is made to replace that".