My transmission when I was whining unusually loud whenever I was in second gear, I also noticed some leakage coming from my transmission. IF YOU EVER HEAR ANY NOISE COMING FROM EITHER THE ENGINE COMPARTMENT OR DRIVETRAIN THAT IS NOT NORMAL, STOP IMMEDIATELY. Figure out what's wrong before you drive on it much further.
Note: unlike my tune-up thread, this one doesn't have as many pictures, my hands were pretty full.
How to: Add more transmission oil to your 5-speed manual transmission.
Difficulty: 2 wrenches out of five. Although this project doesn't require any special skills above operating a wrench, it does require some special equipment.
Grime factor: 2 rags out of five. There is some oil spillage involved, but my hands were clean enough I didn't really need too much hand cleaner.
Completion time: 10~15 minutes. The process itself doesn't take too long, but you have to do some slow pumping, and that chews up time.
Tools and parts needed:
Rags. I used two.
A buddy can come in handy to help you refill your siphon pump.
a level parking spot or a means to level out your vehicle.
anywhere from 1~4 quarts 80W100+ manual transmission oil, depending on whether you are doing a change or fill (I used two, I was in pretty bad condition)
Siphon pump for getting oil into transmission, costs about $5. (Pictured left, sprayer fluid on right is for scale. This is a 1 pint siphon pump)
Means to loosen the transmission nut, I have a modified 3/8" wrench piece, machined down to fit. I will refer to this as "t-fit"
Wrench to fit your t-fit (not pictured).
Ability to operate wrench
Ability to operate siphon pump
Here is a picture of the bolt you will loosen, I took my jeep to the car wash (user-operated quarter kind) and cleaned off my underbody with some tire cleaner and then the power washer, followed by a rag wiping.
To begin, locate the FILL bolt for your transmission. One will be lower on the transmission and was the first one I found. THIS IS NOT THE ONE YOU WANT. If you loosen this one, it will empty out your transmission fluid. The bolt you are after to fill your transmission is higher up, about 2/3 of the way up the tranny (transmission) and I found mine located right above the tranny support strut, as pictured below.
It should be about an inch in diameter. Use your t-fit wrench on this to loosen it. It is a right hand bolt (righty tighty, lefty loosy), but is pretty tight and can take some muscle to loosen. Because of the way it is molded, your t-fit wrench could pop out, some pressure to the back of the wrench to keep it in place may be necessary. The bolt is about one inch long with a pretty fine thread, but once you have it broken loose, you should be able to loosen it by hand. You may want to keep your t-fit wrench on there to give you some grip, it can get pretty slippery.
Once remove the bolt (go ahead and take it all the way out, but be careful not to lose the washer that is on it.), reach inside the hole you just removed the bolt from. Be careful, the threads here can be sharp, so try not to turn your finger too much. Even though you can't fit your finger in there all the way, you should be able to feel if there is any oil on the parts in there (there should be) and if the oil is anywhere near the top. If you have been hearing any whining, it isn't.
Take the top off your transmission fluid (even though some of them come with that ketchup-style squirt top) and stick your siphon pump in, go ahead and go all the way to the bottom to make sure you pull as much fluid as possible. SLOWLY pull the fluid into the siphon. Pulling slow insures that you won't pull air, or if you pull air you won't pull as much. Once your pump is about an inch from being fully extended, pull it out of the oil and turn the tube so it is upright. Wipe it off as soon as possible (from the siphon itself towards the end of the tube) to minimize mess. Place the siphon tube into the fill-hole in the transmission. Push the tube in about as far as you can (the goal is to get beyond that inch of threads in there, remember those?) and slowly push the siphon back in, filling up your transmission. Repeat this process until your transmission starts to drip oil down the outside. You may not see it immediately. I didn't notice mine was dripping until some landed on my elbow, after it had already pooled on my support strut. Once it is full, replace the bolt, making sure to wipe any debris off the bolt as possible. As with all bolts and nuts, start the bolt by hand, tightening it as far as possible before using a wrench. The part may be slick, wiping everything off as much as possible helps. Tighten this bolt about as far as you can go, should be about 40 ft-lbs of force (or about as tight as you can go).
Congratulations! You have successfully added transmission fluid. Give everything a good look over to make sure that all of the parts have been put back in place. Go ahead and start it up and drive around a bit, noting any noises. If you are still hearing unusual noises, have someone who knows what they are doing (preferably a certified mechanic) take a look at your transmission.
As with all my guides, I appreciate any critiquing.