trap1968

Hello everyone. I am new here but have really used this forum many times and it is a great help to me.

I have a 92 4runner 3.0 V6 4x4 with AT.

My transmission OD light flashed on and off and slowly started to slip as my speed sensor failed. I replaced it with a used (but with absolutely perfect gear) and it worked GREAT...for 1400 miles. My speedo started to not function and worked only sometimes. Finally today, it dropped to zero going down the interstate which it had never done before. The OD light stated flashing and I noticed a very, vary slight hard shift going into second gear, Otherwise shifts and runs great except the OD light flashing. I know that the slipping is going to come soon as the sensor starts to fail. (My tranny was slipping badly and OD light flashing horrible before and when I put new sensor in my tranny was 100%)

So when I got home, I started to take the newly installed speed sensor out and it was VERY VERY HOT. I waited 15 minutes and it was still ridiculously hot. I took the sensor out and it was concave and appeared almost melted with the teeth almost gone. Exactly the way the old one looked.

I know that when I replace it it is going to do the same thing and I wonder if anyone has had this problem. I know the tranny issues are the speed sensor but should the tranny be that hot to the touch? Is the heat causing the problem? I know that people talk about replacing the gear only but I do not see any way to do this. It appears "pressed" on the shaft.

Any help would be greatly appreciated. I would not worry about it and use my GPS for the speedo but the shifting issues and slipping caused by the sensor will eventually cause me greater issues so I want to figure out why the gear is getting melted.

Also, the replacement was OEM and the plastic is the same material and melted in the same way.

After it gets soft (which is my theory) it slowly grinds down until it hits a spot and then wears out that spot flat and is stuck forever.

Also, today was very hot day.

Thanks again and thanks to everyone on this forum. It is an awesome resource!!!

trap1968

I really wish someone would try to help me. Even a guess would be great

Thanks so much

aztoyman

I never had a V6 T-case apart but I have had the melted gear on a mechanical speedo drive gear on a 4 cyl case.

It was on a T-case I had bought and I found the damage when I was building it for duals. I don't know how it happened but, the steel driving gear in the case had the teeth all rounded off like something had rubbed against them.

The plastic gear looked what you are describing. If I had put another plastic gear in it would have got chewed up again. I had to find another steel drive gear.

Not sure if this helps. You said even a guess. Is it getting proper lube?