NISSAN XTERRA’S MYSTERIOUS LEAK COULD HAVE YOU HOWLING
I have a 2004 Nissan XTerra with a standard transmission. There is a pretty substantial leak that is dark in color. It looks like oil, but my oil level isn’t dropping.
The leak is under the engine on the passenger side. Since the oil level isn’t dropping, what could it be? My power steering level is fine. Thanks. – Jeff
If it’s really dark, it could be a 2016 Preston Vineyards Petite Syrah, Jeff. But more likely, the leak is coming from your front differential.
Differentials allow the left and right wheels to rotate at different speeds, which they have to do when you’re turning, or you’ll drag your outside wheel all the way through the turn. You have two differentials on this XTerra, because it has four- wheel drive; one on the front axle and one in the rear. And guess where the front differential sits? Under the engine, just to the passenger side of the oil pan. Bingo!
Unfortunately, it’s hard to check the oil level in the differential, because it doesn’t have a dipstick. We check it by removing the plug on the outside of the housing, sticking a finger in there ( the original dipstick!) and seeing if our finger comes out with oil on it. My guess is yours won’t, Jeff. So you’ll save a little money on soap, and you can put that toward your new differential.
Actually, you might be OK. It depends on how low the oil level has gotten and how long you’ve been driving it this way. If you already hear a howling sound when you drive – if you keep looking in the rearview mirror, wondering why the state police are after you -- then the differential is shot, and you’ll have to replace it. But if it’s not making noise yet, you can have your mechanic find the leak and fix it. It’s most likely leaking from the pinion seal, which is right next to the oil pan. Although it could be one of the axle seals, too. Replacing the seals is actually a relatively easy job. It doesn’t require removing the differential, and it’ll probably cost you in the neighborhood of $ 250.
On the other hand, if it starts howling, you’ll need to find yourself a good, used differential, and you’ll be looking at three to five times that price. So stop reading and go get it taken care of now, Jeff.
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