gearbox oil

takza · Post by **takza** » Fri Jul 13, 2007 4:36 am

If you look at the pics in the manuals...the LEVEL of the fill plugs is different...which is why you CHECK the level of the oil...with the car up on a rack..... at the middle plug.

The rear drain plug is loosened 7-8 tirnes to allow the oil to flow back onto the 4WD extension when filling. (there is an oil pump in this extension?)

I once drained only the front 2 and found an extra pint or so of oil at the back plug.

Easiest way is to get it up and level...drain all 3. Put all 3 back in except for the rear one a 7-8 turns loose. Then drop the back down...put 4.1 qts in the front fill?

I think it is better to just change the oil out fairly often...but watch for drips at the axles and at the 4WD shifter arm? The level can get low faster than you think.

sdoan · Post by **sdoan** » Fri Jul 13, 2007 8:18 am

it seems logical to me to remove the rearmost filler plug, remove the front drain plug, let the oil drain, put the drain plug back in, and the fill it up the the rear filler hole. Does that sound logical to anyone else? I just want 2 know why i cant do it that way ha.

I drained and refilled mine yesterday (1985 gearbox in 1983 Terc) and pulled all the plugs and filled from the extension housing. The 3 sections are connected but not so they drain completely. If you only drain from the front you won't get all the oil out of the trans and extension housing (rear most drain plug). For filling I left all the fill plugs out and filled from extension housing - for which the fill plug is on the opposite side of the other two fill plugs (it's opposite the speedo drive). As the oil started to run from the the fill plugs I put them in one at a time. From below the car the rear-most fill plug appears to be lower that the other two but it's an illusion - oil ran from the front two filler holes before running from the extension housing.

If you want all the old oil out, drain all three sections. To prevent air blockage when filling remove all the fill plugs when filling.

BTW I drained and refilled the rear differential at the same time and it was much dirtier than the trans oil, so maybe worth a check.

Hope this helps.

Shawn

Mac · Post by **Mac** » Sat Jul 14, 2007 2:50 am

the fluid all mixes with each other anyways, the owners manual said the transmission takes 4.2L (i beleive) and thats how much oil i put in. thats where my piece of mind comes from.

Chris · Post by **Chris** » Mon Jul 16, 2007 6:57 pm

According to the 1986 FSM.........

Drain oil from all 3 drain plugs.

For 4WD w/ manual transmission
To Fill:
Tighten front 2 drain plugs, leave rear drain plug loose by 7-8 turns.
"Add oil until it begins to run out of the filler holes" Note that it says HOLES.
"NOTE: Always fill from the transfer adaptor filler plug."

Capacity: 3.9 liters, 4.1 US quarts

Typrus · Post by **Typrus** » Mon Jul 16, 2007 7:04 pm

Whatever. Either way, my tranny has survived my abuse, full on oil, when I did it the way I did.
And thats that. Even if I did "screw up" it worked for me.

mightyterc · Post by **mightyterc** » Tue Jul 17, 2007 5:02 am

sorry if i sound like a deadbeat, but i still don't understand why you need to loosen the rear most drain plug! is it for air flow or something? Or is there just something really obvious that doesn't seem to be going through my thick skull?

sdoan · Post by **sdoan** » Tue Jul 17, 2007 12:28 pm

Tazka answered it...

The rear drain plug is loosened 7-8 tirnes to allow the oil to flow back onto the 4WD extension when filling. (there is an oil pump in this extension?)

mightyterc · Post by **mightyterc** » Thu Jul 19, 2007 3:42 am

cheers