Hey guys, thanks for letting me join. I have given my 94 splash to my daughter. It's been a great truck for over 10 years that I've owned it. It's a 4x4 with a rebuilt trans that I got from ford around 8 years ago. Here's the problem that she's having with it... it will up shift and downshift for no reason when cruzing or increasing speed . I've replaced both speed sensors , in the rear and in the transfer add where the mechanical speedometer cable drives from. When it acts up the speedometer will drop to zero and bounce. Would the speedometer cable friction mess up the speed sensors reading??? I don't know which speed sensor controls the shift either??? Any help is appreciated the truck only has 275,000 miles so I know that doesn't have anything todo with it. Thanks for any help in advance.

 

HI and welcome, kind of sucks that you waited to join us until after you gave your Ranger away. LOL

Since your here better late than never.

With the problem you are having, does the OD light flash?

If the speedometer cable is dry rusted and binding this could cause the gear that drives the speedometer cable to strip out.

If this were my truck I would remove the speed sensor and gear from the transmission.

Inspect the gear to see if it is showing signs of stripping out.

Put your finger inside the hole where the gear gets inserted and feel the gear that drives
the speedometer sensor making sure it is still attached properly to the shaft.

If the plastic speedometer gear is stripped or not, remove the gauge cluster inside the truck pull the inner speedometer cable out with needle nose pliers.

Inspect the cable for damage if the cable is intact use white lithium grease from a tub not a can to repack the cable with grease.

To do this grab a handful of grease and squeeze the cable from the top with one hand the other pull the cable while squeezing.

Do this over and over until the cable is good and lubricated.

If your doing this correctly much of the grease that was in your hand will disappear into the cable.

Make sure to inspect the cable closely before lubricating it, just one frayed wire will slice your hand up.

If the cable looks damaged in any way replace the entire cable both the inner cable and the outer sleeve.

If you find the plastic gear has stripped out you will have plastic shavings inside the transmission.

If this is the case I would plan on servicing the fluid and filter.

From the little you have posted about this issue, The above is where I would start.

I do not know if the above will cure all your problems ( shifting and speedometer problems ) or not, however I always try and start by fixing the obvious known problem and hope
it cures the other symptoms.