Cypher
# ./lock -diff
A few weeks ago I decided it was time to change the transfer case (T-case) fluid and starting doing a bunch of research here on Mud. I found lots of good info in lots of different threads so I thought I would document the work and put everything into one thread. It is definitely a super easy quick one job. The longest part of the process was waiting for the T-case to drain completely. From start to finish, I was done in 30 minutes including clean-up.
Most of the folks on Mud have replaced the fluid with full synthetic. The most popular seem to be Mobile1, Royal Purple, and Amsoil. A few have used the Amsoil Heavy Gear Oil as they tow on a regular basis. Choosing any of the well known name brands is a safe bet. A fluid hand pump will make the job much easier but the T-case can be done with the standard squeeze bottles. Some Cruiser owners have mentioned the synthetic fluid helps alleviate the gear whine that often comes from the T-case of Cruisers on a cold morning.
Here is what you need:
- 1.4 quarts of Gear Oil GL-5 75W-90
- Fill/Drain plug gaskets/washers which are a couple of bucks each from Toyota (part number: 90430-18008). These are not required and the old ones can be reused of they are still in good shape.
- Latex or similar protective gloves (if you have ever smelt old gear oil, you know that you DO NOT want to get this stuff on your hands)
- 24mm or 7/8in socket/wrench
- 12mm socket/wrench
- Paper or shop towels
- Drain pan (not pictured)
- Torque wrench (not pictured)
It is suggested to drive your Cruiser around a bit before the replacing the fluid. This will warm up the fluid and help in the process of draining the T-case. Park your truck on level ground to ensure proper drain and fill. As with anytime you are going to get under a vehicle, take all the required safety measures and precautions such as using wheel chocks and using the emergency brake. It is a good idea to clean of any loose dirt and grime from the fill and drain plugs before you start. It is important to not introduce any foreign material into the T-case.
If your Cruiser is equipped with the factory T-case skid (or aftermarket skid) remove this first with the 12mm socket for ease of draining. For those who may not be familiar with the T-Case, it is the the center gear box, on the driver's side of the transmission, that the front and rear drive shafts are connected to.
Remove the fill plug with a 24mm socket. This is important since you do not want to drain the T-case and then not be able to get the fill plug off (rule of thumb for all fluid changes).
Position your drain pan under the drain plug and slightly to the rear of the vehicle, the fluid comes out fast and will overshoot your pan if you are not ready for it. Remove the drain plug with a 24mm socket. Do not confuse the drain plug with the fill plug. Take note of the differences as indicated in the picture below (D = Drain Plug, F = Fill Plug).
Let the fluid completely drain from the T-case.
While the fluid is draining this is a good chance to clean up the drain plug. You will most likely notice a small amount of metal shavings on the magnet the drain plug is equipped with. A small amount of shavings is normal wear. If you have lots, it is recommended you get your T-case checked out.
Replace the drain plug with a new plug gasket. Again be sure the plug is clean before replacing. It is not a bad idea to ensure there is a little gear oil on the threads of the plug. Torque the drain plug to 27ft/lbs. It is extremely important to not over tighten the plugs! You will crack the T-case…
Fill the T-case with 1.4 quarts of fluid or until the fluid begins to come out of the fill location. If the vehicle is not parked on level ground, it is recommended that you at least ensure that you get 1.4 quarts into the T-case.
Replace the fill plug with a new plug gasket. Again be sure the plug is clean before replacing. It is not a bad idea to ensure there is a little gear oil on the threads of the plug. Torque the drain plug to 27ft/lbs. It is extremely important to not over tighten the plugs! You will crack the T-case…
Finally, replace your skid plate and you are done!
Now take your old gear oil to a location that can properly dispose it such as Autozone, Checkers, O’Riley, or the like and take pride in some DIY Cruiser maintenance. FYI, gear oil can be mixed with engine oil and recycled at the same time.
If I missed something or you have a good tip to add, post up!
Most of the folks on Mud have replaced the fluid with full synthetic. The most popular seem to be Mobile1, Royal Purple, and Amsoil. A few have used the Amsoil Heavy Gear Oil as they tow on a regular basis. Choosing any of the well known name brands is a safe bet. A fluid hand pump will make the job much easier but the T-case can be done with the standard squeeze bottles. Some Cruiser owners have mentioned the synthetic fluid helps alleviate the gear whine that often comes from the T-case of Cruisers on a cold morning.
Here is what you need:
- 1.4 quarts of Gear Oil GL-5 75W-90
- Fill/Drain plug gaskets/washers which are a couple of bucks each from Toyota (part number: 90430-18008). These are not required and the old ones can be reused of they are still in good shape.
- Latex or similar protective gloves (if you have ever smelt old gear oil, you know that you DO NOT want to get this stuff on your hands)
- 24mm or 7/8in socket/wrench
- 12mm socket/wrench
- Paper or shop towels
- Drain pan (not pictured)
- Torque wrench (not pictured)
It is suggested to drive your Cruiser around a bit before the replacing the fluid. This will warm up the fluid and help in the process of draining the T-case. Park your truck on level ground to ensure proper drain and fill. As with anytime you are going to get under a vehicle, take all the required safety measures and precautions such as using wheel chocks and using the emergency brake. It is a good idea to clean of any loose dirt and grime from the fill and drain plugs before you start. It is important to not introduce any foreign material into the T-case.
If your Cruiser is equipped with the factory T-case skid (or aftermarket skid) remove this first with the 12mm socket for ease of draining. For those who may not be familiar with the T-Case, it is the the center gear box, on the driver's side of the transmission, that the front and rear drive shafts are connected to.
Remove the fill plug with a 24mm socket. This is important since you do not want to drain the T-case and then not be able to get the fill plug off (rule of thumb for all fluid changes).
Position your drain pan under the drain plug and slightly to the rear of the vehicle, the fluid comes out fast and will overshoot your pan if you are not ready for it. Remove the drain plug with a 24mm socket. Do not confuse the drain plug with the fill plug. Take note of the differences as indicated in the picture below (D = Drain Plug, F = Fill Plug).
Let the fluid completely drain from the T-case.
While the fluid is draining this is a good chance to clean up the drain plug. You will most likely notice a small amount of metal shavings on the magnet the drain plug is equipped with. A small amount of shavings is normal wear. If you have lots, it is recommended you get your T-case checked out.
Replace the drain plug with a new plug gasket. Again be sure the plug is clean before replacing. It is not a bad idea to ensure there is a little gear oil on the threads of the plug. Torque the drain plug to 27ft/lbs. It is extremely important to not over tighten the plugs! You will crack the T-case…
Fill the T-case with 1.4 quarts of fluid or until the fluid begins to come out of the fill location. If the vehicle is not parked on level ground, it is recommended that you at least ensure that you get 1.4 quarts into the T-case.
Replace the fill plug with a new plug gasket. Again be sure the plug is clean before replacing. It is not a bad idea to ensure there is a little gear oil on the threads of the plug. Torque the drain plug to 27ft/lbs. It is extremely important to not over tighten the plugs! You will crack the T-case…
Finally, replace your skid plate and you are done!
Now take your old gear oil to a location that can properly dispose it such as Autozone, Checkers, O’Riley, or the like and take pride in some DIY Cruiser maintenance. FYI, gear oil can be mixed with engine oil and recycled at the same time.
If I missed something or you have a good tip to add, post up!
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