If you're having oil dripping onto your floor on the driver's side, looking like it's coming from the dash, then your oil seals on the speedometer driven gear have failed and it's literally pumping oil through your speedo cable and into your speedo. This was happening to me for a couple months before I finally tackled the repair. In my case, an FJ62, the fix was simple. Drain the tcase, pull the driven gear and its sleeve out (the metal sleeve it rides in is held in place by a small blate bolted to the tcase), replace the O-ring on the outside of the sleeve and then replace the oil seal inside the sleeve. At some point the seal inside my sleeve had fallen out and was missing completely. The new one also slipped right into place with no resistance. Absolutely no force was required to push it into place. This seemed odd, as I would've expected at least a snug fit for a new oil seal. I checked it with my vernier caliper's depth gauge and sure enough it was all the way in (22mm from the outer end of the metal sleeve) and seated. I lubricated it and the O-ring with gear oil and reinstalled. Piece of cake.
Cleanup of the mess, however, was a major chore. While my speedo cable was detached, I pulled the cable itself out and pulled apart my dash. I flushed about half a can of B-12 Chemtool down the speedo cable housing to rinse out the oil and contaminated graphite grease that I had lubed the cable with a few years ago. Since I was taking time to do other stuff that evening, I left it hanging loose overnight so all the Chemtool could evaporate out. I first pulled my lower air duct assembly so I could clean it out, and it was pretty gross. I completely disassembled it and soaked it in a 5gal bucket with about 75/25 water and Purple Power overnight.
While that was going I pulled the speedo off of my instrument panel and got the crazy idea to pull it apart and see if any oil had gotten inside. Oh it was worse that I suspected it would be.
Oil had definitely gotten into the housing.
This doesn't look encouraging...
Dude, damn.
It took two cans of plastic-safe electrical contact cleaner to get all the grease and oil out of the mechanism. I was still careful to avoid the digits and the face of the speedo since I didn't want to damage the paint/printing on them.
Cleanup of the mess, however, was a major chore. While my speedo cable was detached, I pulled the cable itself out and pulled apart my dash. I flushed about half a can of B-12 Chemtool down the speedo cable housing to rinse out the oil and contaminated graphite grease that I had lubed the cable with a few years ago. Since I was taking time to do other stuff that evening, I left it hanging loose overnight so all the Chemtool could evaporate out. I first pulled my lower air duct assembly so I could clean it out, and it was pretty gross. I completely disassembled it and soaked it in a 5gal bucket with about 75/25 water and Purple Power overnight.
While that was going I pulled the speedo off of my instrument panel and got the crazy idea to pull it apart and see if any oil had gotten inside. Oh it was worse that I suspected it would be.
Oil had definitely gotten into the housing.
This doesn't look encouraging...
Dude, damn.
It took two cans of plastic-safe electrical contact cleaner to get all the grease and oil out of the mechanism. I was still careful to avoid the digits and the face of the speedo since I didn't want to damage the paint/printing on them.