How to Change Your Acura MDX VTM-4 Differential Fluid

by kenglen76

Thanks to Todd03MDX for all the information in his thread on how to perform the VTM service and to Morph's oil change web page that inspired me to create this webpage.

Disclaimer: This guide is to be used as a reference only. The author is not responsible for any damages. Work was performed on a 2004 MDX. The steps and specifications may differ for other model years.

Supplies

  • 1 Gallon Jug of Honda VTM-4 Differential Fluid (p/n 08200-9003)
  • 18mm & 20mm Crush Washers (p/n 90471-PX4-000 & 94109-20000)
  • Differential Fluid Pump (e.g. Sta-Lube p/n SL4344)
  • 3/8" Drive Socket Wrench (no socket required)
  • 3/8" Drive Torque Wrench (capable of 33ft-lbs)
  • 3/8" Drive Extension
  • Drain Pan
  • Protective Latex Gloves
  • Safety Glasses

Drop the Spare Tire

  • Open the rear hatch.
  • On the hatch threshold (right side) is a small dust cover (labeled "Spare").
  • Pry it open to expose the hoist shaft.
  • Use the MDX's lug wrench to gently lower the spare tire (turn counter-clockwise).
  • Lift up on the spare tire, jiggle the bracket loose and pull it through the mounting hole of the spare tire.

Drain the Differential

  • The fill (top) and drain (bottom) bolts can be seen by looking under the rear of the MDX directly at the differential.
  • Insert the socket wrench end (no socket attached) into the fill bolt.
  • Using firm counter-clockwise pressure loosen the fill bolt but don't remove it. Make sure the fill bolt can be loosened before you drain the differential.
  • Position the drain pan under the differential.
  • Insert the socket wrench end (no socket attached) into the drain bolt.
  • Using firm counter-clockwise pressure loosen and remove the drain bolt.
  • Now remove the fill bolt.
  • Allow all the old VTM-4 fluid to drain.

Fill the Differential

  • Trash the old crush washers.
  • Clean any crud off the magnetic drain bolt.
  • Put the new 18mm crush washer on the drain bolt and insert the drain bolt (clockwise) into the bottom hole.
  • Insert the torque wrench end (no socket attached) into the fill bolt. Torque to 33ft-lbs.
  • Attach the differential fluid pump to the VTM-4 jug.
  • Insert the hose into the fill hole. My hose has a captive device that keeps it securely in the hole.
  • Pump until fluid just drips out of the fill hole. This is probably just shy of 3 Qts.
  • Temporarily put the fill bolt into the differential but don't tighten.
  • Clear the area around the MDX then start it up and drive back and forth in your driveway a couple of times.
  • Remove the fill bolt and pump in a bit more VTM-4 fluid until it just drips out (about 7 to 9 more pumps). You should now have put exactly 3Qts of VTM-4 fluid in the differential.
  • Put the new 20mm crush washer on the fill bolt and insert the fill bolt (clockwise).
  • Insert the torque wrench end (no socket attached) into the fill bolt. Torque to 33ft-lbs.
  • The fill and drain bolts have alignment stripes painted on them. When you properly torque the bolts they should just about line up again like this.
  • Properly dispose of all waste materials.

Replace the Spare Tire

  • Now would be a good time to check the pressure of the spare tire (inflate to 60 PSI).
  • Center the spare tire under the cable. The side of the spare tire that has the valve stem should be facing up.
  • Re-attach the cable by inserting the bracket through the mounting hole.
  • Use the MDX's lug wrench to gently raise the spare tire (turn clockwise).
  • Don't over tighten the hoist shaft or you can snap the cable! Tighten just enough to partially compress the spring on the spare tire hanger. Check this by looking up under the spare tire.

Celebrate