2000 Pathfinder has smells like gear oil

Hi everyone, I have a 2000 Nissan Pathfinder, manual transmission, 5 speed.

When I drive I get a sick smell of gear oil inside my car. I have had this problem before and the fix was to have the ‘vent tube’ on the transmission replaced because it had gotten bent or clogged or something of that sort. When the vent tube was replaced, the problem of the gear oil smell disappeared.

Now, I am having the same problem again. Same symptoms as before. No leaks in the transmission, no gear oil leaking anywhere, no cracks in the shifter boot, etc. I took the pathfinder to the dealer and they said the vent tube was fine, and that they could not find anything wrong. I think they just didn’t really check anything.

Has anyone ever heard of this type of problem before? I can have the vent tube replaced again and hope that it fixes the problem, but I thought I would ask this community first.

Any help you can offer is appreciated. Thanks, Ron

You have two boots on the shifter. The outer boot is really for looks, and has no real sealing benefit. There is another, heavy rubber seal underneath it and the console that seals the hole for the shifter to the interior. If this one has a rip, that will let fumes from the tranmission vent to leak into the cabin.

Hi, thanks for this information. Is there anyway for a novice like me to check this rather than having to take this into a shop? I can do basic stuff like take the console out, etc. But is this seal something that I would be able to see is cracked/broken ?

You should be able to. The outer boot is connected to the console, and the inner rubber seal should be screwed to the floorboard.