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How to Change Rear Differential Fluid 1996-2004 Nissan Pathfinder

Created on: 2018-07-09

How to change worn, dirty, or out of service life rear differential fluid on 00 Nissan Pathfinder

  1. step 1 :Draining the Rear Differential Fluid
    • Have a drain pan ready
    • Remove the fill plug with a 1/4 inch ratchet
    • Remove the drain plug with a 1/4 inch ratchet
    • Let the fluid drain
  2. step 2 :Replacing the Fill Plug
    • Clean the drain plug with brake parts cleaner
    • Place Teflon sealer to the drain plug
    • Clean the threads on the differential with a paper towel
    • Tighten the drain plug by hand
    • Tighten the drain plug without overtightening
  3. step 3 :Refilling the Fluid
    • Place the specified fluid into a fluid transfer pump
    • Pump the fluid into the rear differential until it runs out on the case
  4. step 4 :Replacing the Drain Plug
    • Clean the drain plug with brake parts cleaner
    • Place Teflon sealer to the fill plug
    • Clean the threads on the differential with a paper towel
    • Tighten the fill plug by hand
    • Tighten the fill plug without overtightening with a socket and ratchet
    • Clean the differential case with brake parts cleaner

Tools needed

  • Gear Oil

    Socket Extensions

    1/2 Inch Ratchet

    Pipe Thread Sealer

    Brake Parts Cleaner

    Fluid Transfer Pump

Hi, I’m Mike from 1A Auto. We’ve been selling auto parts for over 30 years!

So, we're going to do a service on the rear differential. We want to pull the fill plug out before we pull the drain plug out. We want to do that so that if we pull the drain plug out, and later you could not get the fill plug out, there's no way to get fluid back into the rear differential. So, we'll start by pulling the fill plug.

I'm going to use a half inch extension, and a half inch ratchet. We'll loosen this up. If there's any dirt in her, and that's preventing you from getting a good fit with your extension, you can take a straight head screwdriver and just scrape out the dirt. That'll help you get deeper in there and then be able to loosen it up, because you don't want to strip this. Pull out the fill plug.

Now that we know our fill plug came out, we can pull our drain plug. Same tool with the drain—we use our half inch extension and a ratchet. Pull the drain plug out. There is a little magnet on here. You can see how much metal is attached to it and this really isn't that bad. None of the flakes are really that big, so, this differential's doing pretty good. This is the magnet on the drain plug.

As you can see, there is just small fine metal on here. If you pull this out, and you saw big metal chunks on here, that would be an indication that the rear differential is starting to wear severely. There could be some damage in there, and that's one thing you want to check when you pull the drain plug out. But this one looks good. I'm going to use some break parts cleaner on this drain plug.

I'm going to clean it up and wipe it down with a rag. Get it cleaned up pretty good. Once that's clean, I'm going to use some pipe sealer, or some liquid Teflon sealer, and I'm going to spread that around. That will seal it a little bit better. I'm going to wipe down the drain hole with a rag. Get some of the oil out of the threads a little bit.

Then I'm going to install the drain plug. Tighten it up by hand first. Get this thread lined up, just like that. Then I'll take my extension and my ratchet. I'm going to tighten this up. It's going to keep getting tighter. It’s never going to snug down to the point of stopping, so once it gets pretty tight, then you can stop. Not too tight.

Now, we're going to add the rear gear oil. You want to use the approved gear oil for the vehicle. You can check the owner's manual. This vehicle has a rear limited slip. You want to make sure that if it does that, you get the appropriate fluid that already has the limited slip additive in it, or you're going to have to add the additive.

I had a buddy, one time, that was doing a rear differential service, and when he did it, he just put regular gear oil in. Did not put the additive in, and every time he'd go to a drive thru, to get a coffee or something.

When he'd go around the turn, the rear axle would just hop and it was because the rear end was locking up when it wasn't supposed to. So, you need to add that additive. We're just using the bottle and a hose on the end of the bottle of the differential fluid. There's other ways you could do this. You could use a suck gun or another fluid transfer method, but this is working for us.

Once the fluid is at the top, and it starts coming out, that's when you know it's full. This vehicle took about three quarts, maybe three and a half quarts, of gear oil. So, we filled our rear differential up so that the fluid's just coming out. I'm going to put my Teflon sealer on the fill plug.

We can reinstall the fill plug. Take my extension and my ratchet and I'll snug this down, the same with the drain plug. It's not going to snug down to stop, but it will start getting tighter and once you feel it start to get tighter, go a little bit more. That's pretty good right there. Take the brake parts cleaner and we'll clean this up. Wipe it down with a rag.

Thanks for watching. Visit us at 1AAuto.com for quality auto parts, fast and free shipping, and the best customer service in the industry.


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