How To: Front Differential Oil Change 2nd Generation Tacoma

Hey Everyone

Long time viewer, first time poster, you know the drill. I've used just about every technical how-to sticky in this forum. They've all been excellent and gave me confidence to complete maintenance on my truck. This is my attempt to give back. I welcome any comments or suggestions, hopefully, it can help some people out.

2nd Generation Toyota Tacoma Front Differential Oil Change
(Completed on a 2008 TRD Off Road 7/27/2013)

100,000 miles is just around the corner and my front differential oil has never been changed. Time to remedy!

Time Required:
Took me about two hours going slow, taking pictures, enjoying working on the truck, etc. If you stay focused and have a fluid pump, no longer than 45 minutes.

Supplies:
-2 Liters of

$26 75W-90 Synthetic Gear Lube - 1 Quart (Pack of 2)

75W-90 Gear Oil
-Differential Plug Gaskets (Optional - see discussion below)

Tools:
-10 mm Hex Bit Socket
-12 mm Socket
-2 inch Extension
-5 inch Extension (Optional)
-Fluid Pump (Optional - work around shown later)
-Torque Wrench (Optional)



Steps:
1. Set the parking brake and make sure you have enough oil and all the tools. This is the area where will be working on today (note the skid plate proximity to drain plug):


2. First dis-assembly step is to remove the engine skid/guard plate blocking access to the front differential drain plug. Four 12mm bolts hold this plate to the frame.

Now with the skid plate removed:


3. Open the top fill plug first! Always want to make sure that we will be able to fill this thing up. The 10mm Hex Bit should be used here. Then open the drain plug on the bottom with appropriate catch bin. WATCH FOR THE PLUG METALLIC GASKETS! One of them stuck to the differential and one of them came off with the plug.

I opted to not get new differential plug gaskets. I have some experience with sealing vacuum chambers utilizing sacrificial soft metal gaskets and knife edge ports. Given the limited pressure environment and the condition of the current gaskets, I feel confident they will retain differential fluid without any issues. I examined both gaskets and did notice the fill plug had a distinct grove in it made by the last installation. I flipped this gasket over during installation to expose the flat side to the sealing ridge. For the drain gasket, no ridge was evident so I maintained the orientation of the gasket. These gaskets are important as they are the method for retaining fluid, if the surfaces look smooth and you've had no leakage issues in the past I would keep the current set. Be sure to clean the magnet on the drain plug well before reinstalling.
Details of the gasket and open differential:


4. Replace the lower drain plug. I couldn't find a torque specification (someone here probably knows!) so I torqued to match the rear differential (36 ft-lbs) or just really torque it down, we're dealing with a steel case (maybe cast iron???) and steel bolts with a limited clearance for a moment arm!

5. If at this point you realize you forgot to get a fluid pump or your old pump has kicked the bucket you can use the following work around to fill up the differential. If you have a fluid pump, well skip this and fill it up! I removed drivers front wheel to expose the fill plug (pictured below). I had an old fluid hose lying around that actually made it from the fill plug to the front spring from which I could pour the oil into the hose.

While not recommended, if you do find yourself in the unfortunate spot of no fluid pump, taking off the front drivers wheel grants more access to the fill plug than from below. I also managed to jam the oil jug directly in there, so you don't even need a hose.

6. Fill till oil runs out of the fill hole, wait for 20 minutes and top it off (I like to allow some time for the fluid to settle into all the nooks and crannies). Torque down that fill hole and you should be all buttoned up.


7. Replace the engine skid plate. Before I reattached mine I cleaned the contact surfaces off so I wouldn't get any weird noises from trapped dirt and rocks between the plate and frame.

Enjoy the feeling of working on your truck!


Really a pretty simple maintenance operation, especially if you've got the fluid pump (I sound like a broken record). Hopefully, this will help someone out!

Zach