Hi I'm new to the forum and bought a new L4600 with regular stick transmission. When I put the tractor in 4WD it seems like the brakes are on when I push in the clutch and let it roll. I was just wondering if this is normal or is this excessive drag that should be looked at? I am burning A LOT more fuel when the 4WD is engaged. Thanks...
4wd drag?
- Thread starter Smith14
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76_Bronco
Member
Equipment
B7200 4WD w/FEL, 4' disc, 4' Brush Hog, 14" Plow, 4' Blade, JD 246 2 row Planter
It sounds more like your putting it in low. Check your labels, and is the H/L selector next to the 4WD selector?
I usually keep it in High 1st gear when I run it in 4WD. When it is in 2WD and I push in the clutch the tractor rolls freely but when I am in 4WD and push in the clutch the tractor stops pretty abruptly.
76_Bronco
Member
Equipment
B7200 4WD w/FEL, 4' disc, 4' Brush Hog, 14" Plow, 4' Blade, JD 246 2 row Planter
That is strange, you wouldn't think it would roll any differently in 2wd or 4wd with the clutch pressed in. Sounds like a good time to put it up on jack stands and and check the front alxe. I hope it's nothing major.
Is it new as in factory new or just new to you?
Is there any bind front to rear otherwise? as in steering bind?
Is there any bind front to rear otherwise? as in steering bind?
gpreuss
New member
Lifetime Member
Equipment
L3200DT w/FEL, K650 Backhoe, 5' Rotary, 40" Howard Rotavator, 6' Rhino blade
The drag ratio is typically around 1.5. On the L3200/3800 Kubota says it is 1.56. They say 1.57 for the L4600. The tire ratio, front to back, should be just a bit smaller, usually 2-5%. This gets quite confusing, comparing turf to industrial to ag tires - you can use rolling circumference or diameter to make the comparison, but they may give different results. The diameter ratio of my R4s is 1.5. I'm think the percentage is more important than if the tire ratio is bigger or smaller than the gear ratio - one way the front is pulling the back, the other way the back is pushing the front.
On concrete, 4wd is a bear to push the tractor by hand in neutral - you are trying to skid the front or rear tires about an inch per revolution. With a loader attached (additional weight on the front tires) this is no mean feat. In 2wd, it is more like pushing a car in neutral. The drag ratio has nothing to do with the engine, clutch or transmission.
In most dirt I don't hear any particular strain when in 4wd vs 2wd, and the tractor tends to roll easily down hill, etc.
If the tractor is used, or the tires are worn check the diameters. Get the proper drag ratio from the dealer - he has it in a book we don't get. They don't have special gearing for the tire type, so it is highly unlikely that you have the wrong gears in the tractor.
The parts manual specifies the number of teeth for every gear in the tractor. You can figure the ratio yourself by counting tooth ratios front and back from the 4wd gear. It is a bit tedious, but when you come out about 1.5 you are most likely correct. I got 1.5526 on my L3200.
On concrete, 4wd is a bear to push the tractor by hand in neutral - you are trying to skid the front or rear tires about an inch per revolution. With a loader attached (additional weight on the front tires) this is no mean feat. In 2wd, it is more like pushing a car in neutral. The drag ratio has nothing to do with the engine, clutch or transmission.
In most dirt I don't hear any particular strain when in 4wd vs 2wd, and the tractor tends to roll easily down hill, etc.
If the tractor is used, or the tires are worn check the diameters. Get the proper drag ratio from the dealer - he has it in a book we don't get. They don't have special gearing for the tire type, so it is highly unlikely that you have the wrong gears in the tractor.
The parts manual specifies the number of teeth for every gear in the tractor. You can figure the ratio yourself by counting tooth ratios front and back from the 4wd gear. It is a bit tedious, but when you come out about 1.5 you are most likely correct. I got 1.5526 on my L3200.
It is factory new with 109 hrs.
No other bind, it shifts in and out of 4WD easily.
I believe you hit it right on. I am using R4 tires. The rear is watered down and not the factory height so I can see now how that would be working the tractor against itself. I can live with the difference since I am mostly working in soft soil and such. I happen to notice it on hard ground and got concerned. So to correct it I would have to experiment with the rear tire height? thanks for everyone's reply. Great info!
I can feel a slight 'drag' in 4wd on my L3800 when clutch is pressed and letting it roll. But not an abrupt slow down. That said, I only use 4wd when needed, both our rigs stay in 2wd 80-85% of the time. You might want to have it check out, being new and assuming it's still under warranty.
The reason I asked was stated above, I wondered if anyone did anything to effect the tires/ratios.
Being in FL I suppose you are operating on sand?
Why have you not added ballast to the front?
How soft are the rears?
Somewhere is a happy medium, you don't want the front so soft that you will roll the tire off using the loader......but I would fill the front with ballast also and reduce the pressure to cause a little more equilibrium.
OP has already stated that he is running low pressure.
For example, guys who 4x on the beach will carry a compressor with them, when they get to the sand they will drop their tire pressures from 50lbs to 5-8lbs. On sand you want to float your tires.
This is the second post today where someone is not reading or comprehending the OP.
OP, if you are running your rears soft you may have altered your RC by 6-8". IOWs if your rear RC is 140" inflated you may actually be at 134", thus a significant change in ratios to the front. Over time you may do damage.
What are the benefits of adding ballast to the front? Would I just add water like I did the rear? If I add air to the rear tires and it raises them, will that reduce the drag and bring the ratio closer to ideal?
If it were me........
I am unfamiliar with your tractor but the rules apply to all 4wd.
Whatever you do to the rear you'll want to do to the front.
If the factory pressure at the rear is 60lbs and the front is 40lbs and I wanted to reduce pressures to achieve better traction on sand, I would run 45lbs and say 28 lbs in the front.......you can play with psi to achieve a balance. You want maximum traction without adversely effecting ratios or the relationship of front to rear.
Again, since I don't know the tires sizes and the amount of ballast your fronts will accept......you may be able to add other 80 to 100lbs of weight to each of the front tires to gain better traction at the front. I realize you can accomplish this by loading your FEL with weight but why not increase traction all the time and balance front to rear?
I have never heard the term "watered down" used when air pressure in a tire is lowered? I assumed he meant he had water in the rears?
I have fluid in my rear tires and none in the fronts. I am not experiencing what the OP is???
I just put more air in the rear tires then gave it a drive. That was definitely the problem. In 4WD it coast much more easily now when I push in the clutch.
Changing the air pressure in the tires, and fluid doesn't change that because the tires still have air in the top, will change the diameter of the tire. This in turn will adjust your ratio.
Park on level cement, fill air to recommended levels, leave loader and implement slightly raised putting all weight on tires.
Find a spot directly centered to the axle and measure the distance between your 'spot' and the ground. Lower rear pressure and measure. Then, calculate the ratio between the diameter of the front and rear tires, then lower the front pressure the appropriate percentage to achieve the proper height.
or....just run the correct pressures like everyone else
On a side note, have you checked that the tires are the proper sizes?
Find a spot directly centered to the axle and measure the distance between your 'spot' and the ground. Lower rear pressure and measure. Then, calculate the ratio between the diameter of the front and rear tires, then lower the front pressure the appropriate percentage to achieve the proper height.
or....just run the correct pressures like everyone else
On a side note, have you checked that the tires are the proper sizes?
I believe the tire size would be correct from the dealer but anything is possible. When I added air to the rear tires yesterday I tried coasting in 4WD with the clutch in and it worked much better than with the lower pressure. I think my problem was that I just did not have enough air in the rears thus changing the height of the tires and the ratio ti the front tire height.Park on level cement, fill air to recommended levels, leave loader and implement slightly raised putting all weight on tires.
Find a spot directly centered to the axle and measure the distance between your 'spot' and the ground. Lower rear pressure and measure. Then, calculate the ratio between the diameter of the front and rear tires, then lower the front pressure the appropriate percentage to achieve the proper height.
or....just run the correct pressures like everyone else
On a side note, have you checked that the tires are the proper sizes?