Massey 2500 Forklift Instant Reverse Transmission

Went today to look at Mf 2500 forklift. Lift is in great shape and The 3 cylinder diesel Perkins starts and runs like a top. Hydraulics for lift mast work good as well as steering.
The problem is the transmission. When pressing either the forward or the reverse pedal the clutch pack doesn't engage until high engine rpm's are reached causing severe jerking. The problem is much worse in reverse than in forward but still even in forward it is not right. I suspect pump trouble and after reaching higher rpm the pump delivers enough pressure to shift the clutch pack but the torque converter is already somewhat locked and causes the rough shift.
Any thoughts on what might be causing the rough shifts? After it shifts it does not slip and has good power. It was about 35 deg.f this morning while I test drove but even after 15-20 minutes of operating it got no better. Oil level is full in transmission and looks clean and bright with no burnt smell. Would like to buy this unit but this transmission has me spooked. I have heard that parts are hard to get and expensive. I have tons of experience working on the old 6 and eight speed transmissions in ag tractors but have never been into one of these.
Should I run?
Thanks for any advice.

When mine did that it was ALWAYS the shift control spool linkage. When they shift right partially pushing either pedal shifts the spool valve for that direction, then further pedal travel gives more throttle. What's probably happening is the spool valve is shifting in late, that will always make them jerk. It should shift FIRST then throttle up. It won't be pump trouble unless it slips with the pedal to the floor. It's just like an automatic transmission, it MUST be at idle during the forward or reverse shift. Idle too high? It's going to jerk. Lube all the linkage well and I'll bet it comes out of it, mine always did unless something is not set right linkage wise.

Lift has been sitting unused for the last several years in a barn. Could very well be the linkages are needing lubed. It just seems strange that you can depress the pedal and engine revs to about 1200 rpm. You can hold the pedal steady at that rpm and then maybe 5 seconds later the clutch pack engages and at that rpm you get a severe jerk. It is worse in reverse than forward. The torque converter is definitely good as when it does go in gear the wheels will spin on dirt. This also makes me think the clutch packs are engaging well. Man I hope it is a simple linkage binding problem. This lift is in great shape otherwise. No leaks and has new tires on front. Sheetmetal is perfect, all lights intact, gauges working and tight steering.

The forward-reverse shift linkage should have a grease fitting in the center, may need a shot. That lever does not move very far either way, so when it does stick, then suddenly move it will jerk like crazy. It MUST shift first before the engine is sped up, like an automatic car or truck. If you dropped them into drive at half throttle they jerk too. Also the auto transmission oil level is it's own, NOT with the separate differential oil which has a dipstick. Type A-Dexron oil is what mine had in the transmission.

Where do you check the torque converter and clutchpack fluid level which is separate from transmission? Is there a dipstick?

If I recall mine had a level plug on the transmission side, same side the brake pedals are on.

Dieseltech, thanks so much for sharing your knowledge and experiences. I still can not find in the parts book a separate reservoir or check plug for the instant reverse oil. I am sure it is quite obvious and that I am missing something due to my ignorance. Keep reading about some type of bushing that gets worn that can cause shifting issues as well. It must be the pivot bushing that is installed into the transmission housing for the linkage pivot shaft. I have read that the unit must be split to repair/replace this bushing. Splitting this forklift does not look easy. Ag tractors are not bad but this lift with frame rails and other parts looks to be a pain. Any body else had experience with this bushing?

Oor MF40 loader has only one dipstick and that there are two compartments and oils is news to me. Guess I'll be looking at the manual again anytime soon. Pretty sure it's TDH fluid in it. Been years.