First and foremost you should not run your router collet without some form of lubricant, and WD40 is OK as a last resort. WD40 is a great product but for this job where the collet is spinning at high revs it is a little on the light side, 3 in 1 would be better if you have no motor oil in your garage, but you can take a little drop off the dip-stick of your car.
A good analogy is a car engine, would you run that with out oil? Same applies to your collet in the vast majority of cases but some collets are better than others, good ones include Dewalt & Elu, some others are OK some times and others are .........well!
I hope that helps and by the way the Xtreme Xtension only need sa mere smear.
