The best replacement for overdrive is distortion.

The best alternatives to overdrive are rated as following:
★★★★★  distortion
★★★★  drive
★★★  distortion pedal
★★★  fuzz
★  boost
★  underdrive pulley
★  no overdrive
★  3m
★  gain
★  shooting powder
★  3m cloud
★  big bud
★  mifi
★  axis 360
★  oneclickdigital
★  tube screamer
★  distortion first
★  boost pedal
★  audible
★  netlibrary
  direct drive
  treble booster
  bios
  top shooter
  bloombastic
  steermouse
  underdrive
  kool bloom
  blues driver
  3rd gear
  drive ford taurus
  jungle fury
  super overdrive
  overdrive pro
  compressor
  recoil
  verizon mifi
  underdrive pulleys
  trucks

Your alternative for overdrive is not listed? Suggest!
Speaking about overdrive, one probably shouldn't forget about fuzz.

Other search terms related to overdrive and their ratings are:
★★★★★ fuzz
★★★★★ blend knob
★★★ compressor
★ kobo
You have in mind a companion for overdrive and it is not yet here? Propose!



Google Trends

Scale is based on the average worldwide traffic of overdrive in all years. Click on graph for more.
overdrive
distortion
drive