I have a 1995 Dodge Dakota 4 cyc, 2 wheel drive, no A/C.
I replaced the front brake pads which were worn but not to the rivets. No brake lines were removed, fittings loosened or any other source where air could enter the system. Yet after the simple replacement, the brake pedal was very low and has not returned to a normal height. I adjusted the rear brake shoes until they drug the drums to where the rear wheels are nearly stopped yet the brake pedal is still low.
The pedal is solid not spongey.
There are only 2 possible reasons why you may have a low brake pedal. Air in the system or excessive travel between linning & rotor/drum.
With that being said, how was the pedal prior to the pads replacement. If it was the same. Then probally you might have a leak in your hydraulic system (ie; brake lines, master cylinder, wheel cylinder, etc, etc, etc. There is also a possibility that there maybe air trapped in the ABS system. Try bleeding the system & go from there. Start with the rear wheels first then the fronts. Also, if your rotors have been resurfaced too many times, they may be too thin. If so, replace them. Visually inspect all the brake lines, master cylinder, ABS unit & importantly the wheel cylinders(inside the drum) for moisture as it may be an indication of a leak.
Hope this helps. Good luck!