It certainly is possible to reuse wheel bearings and the tt hd ones are excellent candidates.
But it takes time, kero, or diesel, or petrol and then brake fluid to really clean the bearings to get all the old grease out, inspect properly for heat discolouration and damage.
Which most pro mechanics do not have the time to do and admittedly at times myself as a hack, when I can get a brand new set of inner and outer koyos (not hd) but still excellent for $40aud odd.
So if I am in a rush like trying to beat the rain , have to do something else which is typical, I grab the spare fresh ones, freeze the race, and pack the new ones much faster than frigging around with the chemicals, respirator, parts brush and air compressor..and chemical left over sludge which is not good for anything really.
I have cleaned and reused and I have used fresh bearings, I personally know what I lean to. Personal choice. I always keep spare fresh wheel bearings.
Or save the old ones for later keeping matching races with bearings, clean up for later on, like ron..some people end up with a bucket full of old bearings.
However upon principal and some endeavour to 'save the planet' we should conserve and preserve something which is totally reusable for 20-60k kms. For the work they do, they are amazing really.
Same goes for rotors, at times it can be faster and not not much more money for new rotors than taking old rotors to the shop and machining them...Toyota dealer would machine them, but it is all in house.
