Hello, I have a 99 Mazda B3000 2WD, I know that it is basically a Ford Ranger becuase it is built by Ford, so Im asking you all for some help with this problem I had yesterday. I was driving along the expressway about 65mph and the speedo needle dropped to 0mph then popped up to 70mph then back to 20mph then to 50mph, basically it went crazy. Then the ABS light came on and stayed on. The truck still drove fine then I pulled over and cut the truck off to see if it would reset, but it did not. So I tried to continue driving home and then the auto transmission would not shift out of first, it seems like it locked up or something. So I had to call AAA to come and tow me home 60 miles. My truck only has 52,000 miles on it. I have babied that truck since I purchased it. It was running perfect when this happened, I never had one problem with it until yesterday, no transmission slippage or anything like that. The only thing I have ever carried on the back is my motorcycle only 6 times. The bike weighs 450 pounds so that shouldnt have messed up my transmission...I dont think. So I called a friend this morning who is a mechanic and he said it may be a malfunctioning speed sensor.....is that true? Has anyone had the same problem? If so where do I purchase a speed sensor because my local Autozone, Advanced Auto and Pep Boys do not sell them. Would someone please help.....I dont know much about these trucks, but I am pretty mechanically inclined and I dont want to get ripped off at the dealer for a speed sensor replacement that I possibly could do myself.:( :( :(

If it is like the 98+ Explorers, I would say that you need a new RABS sensor. It functions as a speed sensor, and took over the functions of the VSS in earlier model years. Again, that's what I would guess if it was an Explorer, but maybe the Mazda is the same way?

I have babied that truck since I purchased it.
There's your problem. Happens all the time. J/K LOL
Wish I could help, instead of being a smart ass.