Gearbox Oil Change

[Terbus_driver]

So I just did a gearbox oil drain and fill on the 4wd wagon and now I can barely select gears.

I used 80-90W Oil as per the handbook
It took about 3.9 litres, filled until it started to come out then put the plug in.

What have I done wrong here?
It was a little bit hard to find reverse before his but nothing compared to what it is now.

[dlb]

changing the oil shouldn't have done anything on its own. if you had problems getting into reverse before, it could be possible that your clutch just happened to give up at the same time you replaced the gear oil. WITH NOTHING IN FRONT OF YOU, you could start the car in first, then let the clutch out suddenly, and see if it stalls right away. if it stalls, your clutch is ok. if it doesn't stall or takes a while to, the clutch is worn out.

[Terbus_driver]

Even with the car turned off I cannot get into gears. It's like something is jamming the movement. But 80w90 isn't that thick and the temperatures here at the moment are above 10 degrees Celcius

[dlb]

ambient temp was my next question. huh. is it stuck in a gear or neutral?

[Terbus_driver]

in neutral i am fairly sure. if i really force it i can get it into 4th.

[dlb]

if you put it in 4th and start the engine, can you feather the gas and get the car moving? does that change anything at all? can you stall it out by letting the clutch out suddenly in 4th? i want to try to confirm that the clutch is definitely not the issue.

[Terbus_driver]

Just went to try this and now I can't even get the gear lever to move at all. I'm unsure whether it is in a gear or not now. I could try pushing it.
The 4wd selector appears to work fine though.

[dlb]

the 4wd shifter should work fine as long as there is no tension on the rear driveline so that doesn't indicate much.

there are quite a few things that could cause it to be stuck in gear. do a search on here for 'stuck in gear' or something like that. xirdneh has taken apart quite a few transmissions and found different causes. here is one.

viewtopic.php?f=2&t=9971

but i think he has run into a few other causes.

did you shift gears while it was dry of gear oil? did anything unusual happen when you parked the car, or since then?

[Terbus_driver]

With the help of a friend, we might have figured out how I managed to bugger this up so badly.

So... if you look in the workshop manual, it says there are 3 filler plugs for the 4wd gearbox. 1 on the right-rear (transfer case), another on the left-middle and a 3rd at the front-left.

What I failed to realise was that the middle one was on the left, not the right. I undid a bolt that was about the right position for the middle filler plug but on the right hand side. My friend suspects this was a "check plug".

So, the car was in gear, possibly first when I pulled this plug out, I didn't change the position of the gearstick while it was out but somehow it has become unaligned when I put the bolt back in.

Will jack the car back up tomorrow and pull this plug out again and see what I can see in there and attempt to align it. I am not very familiar with the internal workings of a gearbox.

[dlb]

that's really curious. i don't have any t4 transmission experience beyond replacing the gear oil and some seals so i don't know anything about the plug you're talking about. hopefully xirdneh or gottolovem will see this and chime in, as they both have some t4 trans experience and might be more help.

btw, did you keep the rear drain plug unscrewed 8 turns while refilling the trans? that's not a cause of your current problem but the FSM is adamant that it is important.

[drege]

hmm, when I was disassembling a tranny with a eaten input idler gear I notices many of these such plugs that when they came out have springs keeping ball bearings in place, I believe most were associated with the shift shafts.
But there was other stuff that these "plug" things were doing aside from shift shafts - look closely on the ground where ya'll did this for springs, bearings or steel cylinders about 6mm by 12mm long, a subwoofer magnet could help if it was a dirt or gravel lot.

Another possibility is gear slam, but unless you drove between the fluid change and the failure I don't think this is the case.

[xirdneh]

sounds like you pulled the reverse pin
the plug has a pin about 1/2" in diameter and the pin is an inch long or so
inside the tranny the pin slips into a "U" shaped fitting that is attached to one of the shift shafts
you will have to get that "U" back in the right posistion before installing the plug/pin
might not be easy to do

[Gottolovem]

Xirdneh is the one with the most tranny knowledge around here.
Can you get a good photo posted of the plug/pin you used to fill with?
That will tell us for sure if you used the reverse pin in question.

[Terbus_driver]

Bang on the money there xirdneh.

So I jumped back under the car today, pulled the pin out and it was as you described. Oil started to come out too which was filled with metal fillings.... not good. I had a fiddle around with the gear stick until the pin went back in with ease. All the gears appeared to work too now. So I dropped it down and tried to reverse out of the parking spot.... absolutely nothing upon releasing the clutch. Pushed it back and went for a drive, all the other gears work fine though. I guess I stripped all the teeth off it or something when I put the pin in wrong the first time and reversed back.

[Gottolovem]

You would have heard HORRIBLE grinding for quite some time to wear away all the teeth.
If you can figure it out and need a replacement part I know i'll have it so will xirdneh.
watch his videos you will learn alot