AUT0MATIC GEAR BOX - Mitsubishi Vehicle Parts & Accessories

if it is knocking in reverse gear , that is an indication that a tooth of the reverse gear or reverse gear idler is badly chipped or broken
it will require a box strip down and gear and bearing replacement
best stick with the same gear box as there may be too many difficulties to fit a different box

Manual remove filler plugs from the side of gear box and transfer case pump oil in until the oil runs out that's the correct level.

Is the gear box still good? In a lot of older tillers the gear boxes go bad. This is normally due to weeds getting wrapped around the tines and rubbing away at the seals in the end of the gear box. If you have to add oil (grease) then the seals are probably leaking. You should not have to open the gear box up, there should be a plug in it. The plug should be about half way between the bottom and top of the gear box. You should be able to fill the gear box up to that plug with a squeeze bottle. Please rate my answer so I am rewarded points for it.

Possible failure of the linkages, possible failure of the gear notches within the gear box assembly.
This need a closer look from the gear movement levers to the gear box. However if the gear box links are tight then the gear box needs an overhauling.

I take it this a manual gear box and the seal you refer to is the pinion output shaft seal? It sounds like your gear box has a severe fault, maybe a chewed up bearing and this is causing the output shaft to precess which will open up a small gap with with the seal allowing fluid to exit. When the seals were changed what did the transmission oil look like?. Was it opaque and murky - it should be clear and red. Drain the gear box and collect the fluid through a muslin cloth and then insert a finger in the drain plug hole and feel around the base of the gear box. If there is a thick layer of fine grey paste on the gear box bottom plate this is bad sign it is casing material. Does the muslin cloth contain any particulates of hard metal, theses are fragments of case hardened gear teeth. If so the gear box is done for and will need replacing. It might be possible to repair the box but the chances very much are that getting a good used one from a reputable breaker will be much cheaper. Always do the finger check on a gear box when drained of fluid - the stuff that sticks to your finger will tells you a lot about the general condition. A good gear box free of wear has no deposits.

Sounds like a piece of linkage came loose. If it were an internal tranny problem, doubtful that the stick would be loose. Examine all linkage for something very obvious.

buy manual, check capacities

Often the transmission will clunk when first starting up and shifting into 1st. gear. To help alleviate this, hold the clutch lever in for thirty seconds or so before making that first shift into gear. This should make shifting into first much quieter.
This situation occurs on most of the FJRs, even when new.

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