F250 94 No speed marks

Good morning

I am new user of this forum and I go to you because I have a detail with my Ford F250 1994 truck.

About 2 weeks my truck stopped marking the speed, initially the needle moved quickly irregularly and then behaved well. From a few days here, nothing is marked. All other instruments work well on the board. At the same time that the velocimetro fails a focus on the board that says ABS.
Do you know what the problem can be and what should I do to solve it?
Cordial greetings to all and I appreciate in advance

It would be recommended that you look if the speed is marked by inductive sensor or by a serva, since if it were the latter, the case could have split and not detect speed signal the ABS would stop acting.

Hey friend, I had a similar problem with Ford F250 Mod 94 but this was Standard I don't know if yours is automatic and that has something to see or influence. Well, the following was done, the speed sensor is changed in the differential, he continued without marking the speed, so the wiring was checked, from the differential to the fuse box, they are located in a box on one side of the air filter, in that part I detect an internship cable, it is repaired and that was the fault, even that it can be the sensor sensor vs. Story serves you.