Speed Sensor Out Of Wack?

[etnies86]

I put my camper on the back and the flat deck with all the toys this weekend and hit the highway. About a half hr into it I noticed I was only going 70 so I gave it some gas and I couldnt get it to 100 km/h so I called my buddy who was folllowing me and asked him how fast he was going he said 115.
After coming to a complete stop it was fine again.
Got home from the weekend unloaded everything and took a drive noticed it was out again I was doing 60km/h on the highway and gaining on everyones ***.
I pulled over and restarted the truck it was fine again
Just wondering if anybody knows whats going on
Also I noticed after unloading the trailer I put the truck in gear and it was sort of shaky like a bad injector?
I walked on it and it went away its been fine ever sense.

[NYC F-350]

You might has a bad VSS sensor. That is the ABS/speed sensor sitting on top of the rear differential.
If you haven't changed your rear diff fluid recently, now might be the time to do that. This would give you the opportunity to inspect the 'sun gear' that the speed sensor "reads."

You should probably start by checking the plug on the sensor. Just make sure its plugged in all the way and the wiring looks good.

You can also remove the sensor and clean the gunk off the end of it. Just wipe it clean and see if that helps any.

[etnies86]

I will give that a try and yes just changed the fluids in the rear end 4 weeks ago

[NYC F-350]

Could you have either bent the sungear or whacked it somehow and broke a few teeth off of it? That would explain your issues as well.

[etnies86]

All the wires and x