Instructables
Most people ignore transmission fluids. Even worse most people only talk about the importance of flushing an automatic transmission. If you have a manual transmission automobile, don't neglect that gearbox. Old oil can have metal shavings in it as well as sludge build up. Just as with motor oil, and oil change is cheap insurance. This instructable I'll show you just how simple this process is.

Step 1: Gather your tools.

Gather the tools and materials you will need for this job.

You will need:

- Jack and Axle stands or tire ramps to get your car off the ground
- Set of wrenches and ratchet set (depending on your vehicle.)
- Torque wrench
- oil drain bucket of some type
- Fluid pump
- rags
- WD - 40 or a penetrating oil
- Gear oil (most likely 75-90 or 80-90, check your owners manual)
 
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isaacwilk3 months ago

is using a gas torch safe around oil?

gearboxes1 year ago
I have a few problems with this instructable.
1/ Oil draining and filling must be done on the level so ramps aren't enough and must have jacks at the other end.
2/ Modern oils are vehicle specific and the wrong oil can cause expensive damage to a gearbox. (If you put EP oil into the illustrated Nissan you will not get 2nd gear on a cold morning)
3/ On some front wheel drive gearboxes the bung that looks like a filler bung is only a level bung. If you get it wrong you're putting no oil into some of the gearbox.

Having said that changing gearbox oil is a great idea. I owned a transmission shop foe 40 years, most of my work came from poor maintenance.
JCK7 years ago
These are pretty good instructions I just think you left out a few details that may help. Make sure you have the correct fluid for your trans. the owners manual is not the best place to find out pull the fill plug and stick your finger in there to be sure. Some manual trans. take 10w30 motor oil some take dextron auto trans fluid some take hypoid oil. It can be different in the same year, what is in there is correct regardless what the store/manual says. The fluid should be changed while hot or at very least warm It's not very safe or fun but it is the best way to get all of the grit out. It also makes the plugs easer to remove. If you have a plug that wont come out wire brush all around the plug before you use the penetrating oil or torch helps the oil wick in the threads and reduces the risk of setting the trans on fire. I also change the fluid in the rear end at the same time because nobody ever thinks about the rear fluid until it fails or starts making noise.
glad2bjstme JCK2 years ago
what do you mean by rear fluid? I am new to the car repair thing.
He's referring to the drive axle(s) in rear-wheel drive and four-wheel drive vehicles. The drive axle(s) have differentials in them and the fluid in these assemblies must also be changed periodically - typically at the same time as the transmission oil. In 4WD vehicles there is also a transfer case bolted to the rear of the transmission, and it, too, requires period oil changes.

If your vehicle has front-wheel drive, your drive axle and transmission are built as a single assembly known as a transaxle.
germanpickle (author)  JCK7 years ago
Never trust the oil that's in your vehicle as being the correct oil, unless you know the oil is factory original, or you know exactly what went in at the last change. Don't trust what a shop tells you or what you requested to be used, as all too often shops will cut corners. I'm sorry, but i couldn't disagree more. The manual was written for your vehicle and will mention what oil you should use for the driving style, and temperature you're driving in. In some cases there are a variety of transmissions for a specific vehicle. If you're not certain contact dealer, as they will know what goes in the car.
glad2bjstme2 years ago
I have not tried to change my gear oil yet but Thank you for instructing on this subject very helpful. So do I really need a torque wrench?
Hugh Jorgan3 years ago
Cheers Matey, a brilliant step by step set of instructions for those of us who havent been blessed in the brain department.
I am now going to nip out to my garage and change my gearbox oil. I wasnt confident enough to tackle it myself prior to your instructions, so once again CHEERS !
lilroud3 years ago
I changed mine in my 91 Geo prizm about a month ago.... it was a 24mm socket for the fill an drain... my fill was boogered up and the socket didnt work... I used PB buster and that stuff is amazing, it is magnetically charged and can actually work its way up hill..... i let it soak for about 15 minutes and only had to use one hand and some good vice grips to break it free
I have a 1997 jeep wrangler 5 spd.  I know where and how..... but I just cant figure out how to get the oil into the filler hole.   I tried a siphon tupe but that just ended up being fubar.  I saw some mention of pumps.. I wasn't able to find one at the parts store -- suggestions there?

Also -- I agree it is important to do as I just bought this tranny brand new after 160k mi (oops) I torture the poor girl.  But I had a 1989 VW that I drove very very hard for 380k mi -- never replaced the clutch never touched the fluid, what did her in was a moose in Maine. -- so you never know
If your local parts store does not stock them then find a different parts store! Go to the counter and ask for a gear oil / lube pump! it looks like a over sized hand lotion pump with a small hose attached They are running around $12 on Ebay depending on the requirement of your car you will need 1 to 3 Qts of either 80-90w gear oil (lube) or 120W I recommend you have 2 sets of old clothes a sheet of painters plastic and keep young children out of the area because of a PG rating on your project! :> once you have the fluid drained & have replaced the drain plug it is just a matter of pumping the new lube in to the tranny do not worry about overfilling the tranny once it starts coming out the fill hole it is full. hopefully you put plastic under the car before you started makes clean up easier! also cover the drivers seat because you will want to move the car for clean up. Now for the reason I said 2 sets of old clothes one set you will throw away. The other set will get you in the house and to the shower. Nothing in your car smells worst than gear lube! If you can work with the wear a pair of vinyl gloves (Saves time in cleaning under your nails)!
2 stroke 4 years ago
thats anice truck id love to get that for my first ride
JCK4 years ago
I got my gear oil pump @ pep boys they screw on to the quart bottles. If you are using ATF get a small spout that screws onto your oil bottle and put a vacuum/fuel hose on it and squeeze it in. or a really long hose and hold the bottle above the trans. level.
Robertez5 years ago
The drain plug on this Nissan pickup fits a 1/2 inch drive ratchet not 3/4 inch drive. The filler plug as stated was removed with a 17mm wrench. Loosening the filler plug first is a very smart move. Let’s say you removed the drain plug and the filler plug is stuck. Well now you have an empty gear box and no way to fill it. Wire brush the filler plug before removal to reduce the possibility of contamination. Just changed tranny oil on my 91 Nissan pickup with your help! This site ROCKS!
yaguarete795 years ago
Hello, I found it very helpful because everybody just speak about "automatic transmissions" blah blah. I have a 1985 Nissan Pick up truck (yeah, a relish, I guess) and wasn't sure if I could change the trasmission fluid. Now that I know it's not only possible, but necessary, I'd like you to help me by telling me where can I find the refill cap? I mean, usually every refill cap is easy to locate when you open the hood. But in this particular case.... I cannot locate it. Can you please help me with this? It would be very appreciated. Thank you in advance!
ya my friend has one of thoughts and its trany is all burnt up i had to drive it today
is it a manual? if so than you can just take the shifter out and fill it there. that is if you know how muck your tranny needs. my 2 ton 465 only took a gal. and a half but this is a heavy transmission.
germanpickle in your instructions for manual transmision oil change you mention gear oil are you talking about trans. fluid my owners manual recommends mercon ATF fluid for my 1996 ford mustang manual transmission
most manual and auto tranys after the mid 80's use dextron mercon instead of gear oil.
Very good, human
wtf the robots name has a line through it
Derin Derin5 years ago
He is somehow banned
Derin6 years ago
isnt there a filler cap under the hood? the hood is the place of all fill caps
hondagofast7 years ago
When there are metal shavings in your oil, that means something is wrong with your transmission.
germanpickle (author)  hondagofast7 years ago
Whereas your comment holds merit, it's not always true. For example. A transmission that has been abused (IE Shifted hard,grinding gears etc.) you will find slight metal shavings. This is from when the gears rub together. causing bits to come off. Lets remember I'm also referring to vehicles with higher mileage. the truck in this photo has almost driven the equivalent distance as the distance from earth to the moon. Although it's a sign of heavy wear it doesn't mean that there is a problem..... yet. Furthermore, on motorcycles, the clutch is bathed in the same oil that lubricated the motor and transmission. The steel clutch plates wear which in turn puts more shavings into the oil. One of the reasons why it's so important to change your motorcycle oil more often than in a car, and always do a filter (which I do on a car each change too.)
My family's old 92' Honda Accord has gone 235,372 miles and there aren't any metal shaving in the transmission fluid, and my sister drive it for a few months, destroying the clutch in the process.
a. Manual transmissions use oil, not transmission fluid. b. The clutch is not housed in the transmission.
Hondas with manual transmission use regular engine oil.
flee20106 years ago
I was told that I shouldn't change my manual fluid because I had no clue how long it had been since changed. (the car has 215k miles on it)They said that the metal in the fluild might actually be acting as good friction by now. And if I changed it it would shock the system and it would be hard to get the transmission in gear. I ignored this warning and took it somewhere else and got the proper gear oil put in. Well it turns out they may be right. The tranny felt alot smoother between gears, but it seemed I had to try harder to get it in the gear. I hope it will get better, but exercise caution. As long as you have changed the fluid every 50k miles or so, the guy said you should have no problems when putting new fluid in.
nice antenna
germanpickle (author)  lookatmygrlyfont7 years ago
My antenna was stolen, and this one was on the $0.99 rack in the Surplus section of Princess Auto. I was going to get the Folgers coffee can exhaust to go with it, but decided against it at the last second. ;-)
Well done, helped me to get started and do it right.
engrmurad7 years ago
engine and transmissionthe question one is whats about price & other is, ifthere is no drain plug, you have to drop the pan and let out the fluid. One of my cars had a drain plug, but although the manual said the transmission had a 7 quart capacity, only 3 quarts drained out of the plug. The car had a second part of the case that held fluid, and a hump between it and the drain pan. Getting access to the second area would have required removing the engine and transmission.
However you may buying a pump and not being able to get any fluid out the automatic transmission dipstick tube.
shadetree7 years ago
THANKS FOR THE INFORMATION. IT WAS VERY, VERY HELPFUL. I WOULDN'T HAVE KNOWN WHERE TO START IF IT WEREN'T FOR YOU GUYS. THIS SITE IS THE BEST!
Gnaw7 years ago
Well done. Great photos, instructions and many helpful suggestions. Thank you
qolque7 years ago
Thanks Germanpickle, good info. I lost an auto tranny ('93 Chevy truck)to not servicing through ignorance, and was told manual shift didn't need the flushing. I may be able to prevent a similar loss on my 98 Jetta. Thanks Wulf for the fluid warning. Good to know before I start.
Wulf8 years ago
Be aware that manual transmission fluid just stinks as hell, it's nothing like the engine oil. Get industrial gloves, lots of old newspapers to cover the ground and of course, rags.
But later on I also had to replace the alternator (twice), replace the fuel pump and filter, the emergency brake line was corroded so it too was replaced, and replace the head gaskets (all the way at the bottom of the engine). I've done alot to my SUV in the past year considering that I only just bought it in Nov. (I think), but then again it's a 1993. Now my brake lines have a hole in them somewhere, so I had to back it down our hill using the emergency brake (good thing I made sure that it was tight) and what little bit of regular brakes I had left. I'm happy that I have a medium sized SUV, cause I can actually get underneath it without having to jack it up. So many problems, so little time..... As I said before, excellent instructable.
Good job, I just changed the transmission fluid and filter in my Explorer about 4 months ago (it's a 4x4 automatic). I also changed the engine oil (and filter), upgraded all my spark plugs to the Bosch +4, changed the air filter, replaced the rear shocks, and the front and back brake pads (I like to get everything done at the same time, unless it doesn't need it). Hey, I also have those fog lights (except they have black housing), but I placed them a little closer to the middle.