Original jd450. HLR transmission with 4 speed ranges. Tranny works fine for about 1/2 hour until everything heats up. Then gradually worsening, it some times doesn't move when shifting gears. Sometimes just "nothing", sometimes a little strain as if clutch is slipping. Shifting repeatedly will eventually result in Tranny "taking hold" and move again. After 45 minutes or so, just have to park it. Let it cool completely down, then next day same thing. Works good for 30 to 45 minutes, then same thing as above. Dittos for left steering clutch. Hard to pull, but works ok for 30 to 45 minutes, then gradually becomes useless. Any ideas are greatly appreciated Stacy
Start with the two part clutch adjustment, then it's on to checking reverser pressures. The left steering clutch, doesn't release, steering brake doesn't take hold, or the left track doesn't want to drive?
both sides pull fine. Right steering clutch and brake work fine. left steering clutch is hard to pull back, but clutch and brake work semi-ok when cold. When hot, the steering 'brake' does not seem to hold hardly at all, even with stick pulled all way back (but the left steering clutch does disengage properly)
I know this is an old post but did you ever find the solution? I’m having exact same issue.
450 straight HLR pressure is 140-150 psi at 1800 rpm ,oil temp 150 deg F. Check it cold and then hot. I bet there is a significant pressue drop when hot and not in spec.
My money is on the clutch adjustment. More on the hydraulic adjustment than the mechanical adjustment. Jeff, do you have a pressure gauge?
Has the fluid and filters been changed yet? Old clogged filters/bad fluid is another possibility. Ran into the same problem on a 550. Would run perfect for 30-45 min and then would start slipping and eventually just not move. I would let it cool down and then it would run good.
Thanks for the replies. I changed all filters. Cleaned the pickup strainer. And I changed the larger spool valve in the hlr selector manifold. All to no change pushes strong cold and barely at all when hot
I’m getting a manual in the morning.
Mg I do have gauges but I have no knowledge of the procedures for diagnosing the problem
How did the fluid look that was in the filters?? Did you change fluid also? What hydraulic fluid do you have in it?
I flushed the system with diesel fuel and replace hitrans wolf head oil.