ed
the drive motor seems to engage more fully when there is addition load ( whether tilt or lift) on the hydraulics, lowering the lift seems to have no effect ( just bleeding hyd not powering) there is a little hissing sound that disappears when the hyd are used and seems to coincide with increased motor "grab"
i have not noticed any affect of steering on the drive, but need to investigate further. ( i am trying to avoid turning at high speeds for obvious reasons)

it is fully serviceable at this point, and i am happy to show improvement after cleaning linkage.

is it common to have reverse set to a higher max speed than forward?

if you are positive that the tilt may have something to do with it, then you may actually have a broken axle and bent axle housing, with the way the axle is sheared allowing it to keep turning in rev but when the pressure is on the axle housing tiling, it causes the axle to slip. in 35 years looking at forklifts, I think I have only seen this 1 or 2 times.
if you get the wheels in the air (watching carefully for anything odd while getting it in the air, like one side of the mast or axle twisting), and take off the park brake, do both sides drive wheels turn the same by hand in both directions?

well i cleaned and lubed the linkage. and it seems a bit better , though nothing seemed to be moving more than i did before.
i am not getting a whole lot of action on the left brake on the motor disengage (linked w the handbrake)

reverse seems much better but i still get a noticeable increase in engine engagement when i move the tilt for or aft while going forward.
i will explore and clean further
thanks ed

ed
thanks again, i will check out the steering and look at the linkage at the pedals and will post my results hopefully thursday ( i have a long day out of the shop tomorrow)

my bad, I didn't recognize that it was the motor that was acting strange heck without my coffee, I thought it was an electric forklift.
, and no, as far as I know there is no "centripical" or centrifugal clutch on these. BUT there is an "inching control" in the transmission, as well as "solenoid actuated modulation" valves that electrically control pressures in the transmission for direction (holding pressure to the clutch-packs). I think you may find the cable that operates when you depress on the left most brake pedal (and doesn't move when you press the right pedal) may be sticking or out of adjustment, or other parts of the same control (the spool might be sticking as it returns into the transmission valve body)

Also there is a "priority" valve that keeps the proper amount of hydraulic pressure on the steering system. does steering do anything to the symptoms you mentioned?

thanks for the quick reply ed
i am not sure i understand.
i will look at the linkage, but when i press the accelerator, the motor revs but acts its like the clutch is slipping ( there is no clutch pedal) is there a centripical clutch like on my son's honda 50?

due to slop in the hydraulic levers, the linkage is engaging (or failing to engage and close the related switch