High gear issue

DonoKubota

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Equipment
B2650
Mar 13, 2023
1
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1
Indiana
Hello, I have a B2650 hydro tractor with 20 hours on it and when I put it in high and rev up the rpm's the forward and reverse treadle pedal becomes extremely hard to press down in forward or reverse, any thoughts?
 

85Hokie

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BX-25D ,PTB. Under Armor, '90&'92-B7100HST's, '06 BX1850 FEL
Jul 13, 2013
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Let me understand you better.

The physical pressure on the pedal changes with the gear changing?
 

kubotafreak

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GRAND l6060, L3560, B6100, gr2100, tg 1860, g1800, g1900, g2160
Sep 20, 2018
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Have you checked the fluid level of the transmission lately? Assuming oem sudt2, so fluid type should not be an issue. What you describe is a byproduct of the hst. As the trans input speeds up you are shifting more inertial weight changing the volume of the driven pump(motor). You may try to use less rpm. I would also check to make sure the brake is disengaged, and it wouldn't hurt to change the hydraulic/hst filters early.
 
Last edited:

nbryan

Well-known member

Equipment
B2650 BH77 LA534 54" ssqa Forks B2782B BB1560 Woods M5-4 MaxxHaul 50039
Jan 3, 2019
1,161
705
113
Hadashville, Manitoba, Canada
Hello, I have a B2650 hydro tractor with 20 hours on it and when I put it in high and rev up the rpm's the forward and reverse treadle pedal becomes extremely hard to press down in forward or reverse, any thoughts?
My same tractor is the same. There's no way ALL the torque being asked of the HSD in H range and top rpm, at a stop or nearly so, can get applied to the drive train instantly or the wheels would need to spin. Thus the back pressure on the HST speed pedal - the resistance to flow backs up and exceeds your pedal pressure until you're moving up to speed. The very loud whine of the tranny also indicates too high a torque is being asked of the hst.
It's like, in any gear, you try and advance using the hst pedal while the parking brake is firmly set and rpm advanced. What happens?
The HST whines very loudly and the speed pedal pushes back. Same issue - hydrostatic motor can't turn the drivetrain so pressure builds back against the pedal.
I ALWAYS EASE INTO the hst pedal in H range. There's a "sweet" spot where the back pressure on the pedal and hst noise is monitored as I accelerate slowly. And if it turns out the load and/or road slope rise has me slowing to near speeds of M range at full HST pedal, I downshift to M.
 
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nbryan

Well-known member

Equipment
B2650 BH77 LA534 54" ssqa Forks B2782B BB1560 Woods M5-4 MaxxHaul 50039
Jan 3, 2019
1,161
705
113
Hadashville, Manitoba, Canada
Hello, I have a B2650 hydro tractor with 20 hours on it and when I put it in high and rev up the rpm's the forward and reverse treadle pedal becomes extremely hard to press down in forward or reverse, any thoughts?
Adding to my comment about my experience with pedal resistance under high torque loads, which I see as totally normal as mine has been driving like this for over 1100 hours, I need to add that with only 20 hours on your machine I would try and avoid pushing hard the hst tranny much at all for at least until thinmgs have broken in a bit more. Don't push it much until after the 50 hour initial service, and if it's important to get up to speed quickly in H range at least have the machine thoroughly warmed up first.
i can honestly say my 1100+ hour my 2017 B2650HSD engine, tranny, hydraulic pumps and controls all run smoother and quieter now than at 20 hours old.
MAINTAIN MAINTAIN MAINTAIN. USE KUBOTA HYDRO FLUID AND FILTERS.
I've gone to Rotella T6 5W-40 from the Kubota 10W-30 diesel engine oil and really like how it runs, year around - we get -30C-+30C as a normal yearly temp range. And use Lucas Ultra HD grease for everything.
 
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