Hard to select Reverse & 5th gear

[the_old_diver]

1997 Sharan TDI AHU engine 212k miles. Manual gearbox.

Driving along in the lashing rain on a single track road in the Highlands yesterday the car got increasingly difficult to get into 5th gear. Within 20 or 30 changes it changed from being "normal" to almost impossible. In the supermarket car park it turned out that reverse was also almost unavailable without slamming the gear lever hard to the right. Over the past few days I have been through more deep puddles than usual, and I was put into a soft verge 60 miles ago where the car graunched along the edge of the tarmac, bit I can't see any damage.

Reading what threads I have found, it seems possible that the gearbox oil / transmission fluid is low. I'd like to check it since it has been overlooked in the 15 months I have been running the car. I have just called my local factor and their computer says to get their MV-ATF fluid - at £7.41 / litre. I have been out onto the front lawn in the rain and dark to look underneath, and all I can see is a single hex plug in the forward face of the gearbox, which I have managed to photograph. Photo taken from front of car, camera under bumper next to nearside wheel. The liquid around the plug is wd40, applied in anticipation. Is the yellow arrowed plug a drain, a filler, or something completely else.

Thanks in advance for an answer about the plug and any other advice! OD

[the_old_diver]

Well I spent £14 on 2 litres of red juice, decided that the plug in the photo had to be the fill and drain, removed it, and then saw perfectly clean red juice dribbling out of it. Gave it an extra squirt for good luck and replaced plug. Over a few days selection has become better but not perfect.

I can't even see the gear selector mechanism - think I'll invent an cctv camera on a bendy rod for exploring these impossible locations. OD

[zollaf]

the plug in the photo is indeed the filler/level plug. the drain plug is further back, near the cv joint, but is the same size allen fitting. it may be worth draining the box and refilling it to see if that makes it any better. the selector is cable operated and you can just gain access by removing the fuel filter and the plastic around the battery. there is a single rod that goes down into the selector with a seal at the top, and the lever is attatched to the end of this rod, that the cable at the front attatches to. below the seal is a bearing that has a habit of seizing. it would be worth squirting some wd40 through the seal, using the tube. push a small screwdriver past the seal to make a gap. when this bearing goes you cant move the gearstick left or right, so end up only with 3rd and 4th, but if its starting to seize it may stop the selector going over to 5th properly.

[the_old_diver]

Thanks Zollaf,
I'll give that a try tomorrow. :-)