Hey Guys! So my JD 510 Backhoe has an interesting issue. It has the 8 speed automatic transmission with neutral and park. When it is placed in Park, which is all the way down on the shifter and seen in this photo. It has become harder to shift out of park into gear. It is very stiff and difficult to move the shifter to neutral or a gear selection. If it is tough and I get it in a gear selection, it acts as though the parking brake is still on (which is automatic when I place it in park, I don't have a lever). This means that it won't move but you can feel it and hear it trying to move (RPM slows and sounds under stress like you are pushing against a wall that won't budge). After working the gear lever or moving the wheels with a backhoe push the lever will eventually slide right up into gear with no resistance (like it is supposed to). When it does this, all is fine, all gears work in both directions. I am guessing the parking brake is willfully disengaging at this time. So, I am thinking linkage isn't completely disengaging the parking brake but wanted to throw this out to everyone in case there is something special one of you knows that I don't. I do know that the axle, bearing, rear diff, pinion gears, etc are in beautiful shape and there is fresh fluid from JD in the machine. Any ideas? I may follow the linkage to see if there are any issues sometime today and post anything I find. Thanks guys!
Check your motor supports.Ron G
Motor supports? They look fine. Motor is bolted to the frame on both sides.
Ron means to check your motor mounts for excessive sag. There is usually a rubber element between the engine and frame. When this element shears or sags, it changes the engine/transmission relationship to the frame and controls. ... (gear shifter) I would suggest checking the linkage bushings. If they have too much wear, the shifter handle isn't moving the shift control into the correct spot.
Linkage to the parking brake, parking brake lining may be toast and causing a bind...
I figured that on the motor mounts. Got under it and it seems the motor is directly bolted to the frame on both sides with two large bolts per side. All appears pretty sound.
It went from heat like the surface of Mercury to Heavy rain today. I will get out there and check the linkage soon.
Did some digging in the repair manual. Found a "park lock" linkage location that I will check first.
My dad had a 510 and it would torque lock on all but flat ground when put in park. I think it uses a pawl like automotive trams. In a car. He finally blocked out the slot and used the stab. to park it.
It does have a pawl. Manual has some adjustments to try on it. Looking into it now. Thanks.
By the way guys... haven't played with the pawl just yet, but I ran the machine for 4 hours Sunday and never placed it in Park and just hit the brakes, dropped the stabilizers and went to work (as Repowerguy said his dad did). Didn't have any issues with the tranny or getting stuck in park. When it isn't 1000 degrees here in Charlotte NC I will give the pawl an adjustment per the manual and see if that makes a difference.