Approx two years ago my 140,000+ mile T100 began making a slight clicking noise (non-regular or repetitive and sounds like a marble in the dryer). I inquired of some local mechanics and the Toyota dealership and they said that I wasn't running in 4WD enough. This seemed odd because I get in 20-30 miles/month of off pavement driving and the first thing I do upon going through the gate is shift into 4WD. I started making sure that any time I was off pavement I shifted into 4WD. This seemed to take care of the problem for a while. Some months ago it returned and could be stopped for short periods of time by shifting into 4WD momentarily and then back out.
Now it is constant. It makes the noise while the vehicle is in gear and traveling. If I shift into Neutral the noise continues. Here's where it gets really interesting. If I shift into neutral and increase engine RPMs the noise increases in frequency as well. When the vehicle slows below approx 10 MPH the noise stops and cannot be made to start again until the truck is in motion again.
My intention is to drop the transmission pan this weekend to see if any parts fall out unless someone has a better Idea.
Thanks,
Alan
Now it is constant. It makes the noise while the vehicle is in gear and traveling. If I shift into Neutral the noise continues. Here's where it gets really interesting. If I shift into neutral and increase engine RPMs the noise increases in frequency as well. When the vehicle slows below approx 10 MPH the noise stops and cannot be made to start again until the truck is in motion again.
My intention is to drop the transmission pan this weekend to see if any parts fall out unless someone has a better Idea.
Thanks,
Alan