John Deere cable skidder 540G transmission

[Oxtick]

Transmission is the 8 forward and 4 reverse. No clutch (left pedal is the "inching pedal"). Up and down shifts as it should, except when down shifting from 5th to 4th. It almost stalls the engine with a hard "jerk". Have learned to almost come to a complete stop before shifting, for fear of breaking something ( when going from 5th to 4th).
John Deere dealer mechanic said transmission is shifting gear or clutch pacts when going from 4th to 5th. Otherwise no help.
Not sure if it is something I can repair or even where to start looking. Hoped someone else has had similar problem and what it took to fix.
Has been doing this since machine was bought....would not have bought had I known...live and learn.

[DennisK]

You might need to find an AG dealer/mech to check pressures. Get a Tech manual and build a set of manifold gauges, they connect to the right side of trans, C1, C2,C3, C4, Lube, and Sys pressure. sounds like one clutch is not releasing pressure. Pull the sump screen, brass is brakes, fine powdery is clutch packs, flakes are wet clutch.

[Oxtick]

Thanks Dennisk.
Will look into getting a Tech manual. Checking sump screen is a good idea.
May bite the bullet and have John Deere field service mechanic take a look. 

[Oxtick]

On Powershift Transmissions, like this one, should operator always let off accelerator before shifting ?