The bases of the blades for a tempo rocket blender DLJ-1017 the white plastic part just underneath became soft and friable

Turn the cog in the base a little. Sometimes it gets misaligned.

I had this exact same problem and was scratching my head why would that happen all of a sudden. After taking it completely apart (which I didn't need to), I realized in the end that the cup rim was stuck at the bottom of the blender base. It looked like a part of the base what got me confused the first place. The base of the blender is flat with no ridges around; check if this is the same problem with yours.

If you're in the US, call Bella Cucina at 866/832-4843.

Have you checked Ebay or Sears Kenmore.com

You need to unfasten the white base from the clear jug, then the rotating blade will sit inside the white base, with the blade facing upwards. The white rubber flange goes in next. Then screw the assembled base back into the clear jug. The jug should then fit on to the stand.

The low profile blade is a grinding blade for nuts, coffee beans, spices, etc.

the part is Black and Decker Blender Base Collar Ring BL5000-11
However these are prone to cracking. I ordered a second after my first cracked, and the second one cracked after just a couple uses.

Grease can only creep into the blender vase if the oil seal has worn out, or the blenders blade shaft is worn and wobbling. Try cleaning all parts in alcohol to soften the seals. Rebuild kits and replacement blades can be found here (http://www.brevilleusa.com/breville-parts/blending.html)

Look at the underside of the blade shaft. The metal wing nut on the end of the shaft secures the blade assembly to cream coloured plastic blade base. The wing nut also transmits the drive from the rubber coupling on your blender to the blade shaft. The wing nut has a LEFT HAND thread.
The left hand thread ensures the blade assembly does not unscrew during normal blender use.

Firstly disassemble the blender blade assembly. Place a folded tea towel over the blades and hold the blades firmly. If you do not use a tea towel you may cut yourself.

Grip the wing nut with your other hand and unscrew it CLOCKWISE.
Remove the wing nut. You can now remove the blade from the plastic base.

Put the blade assembly in the new jug and offer up the plastic base from under the jug so that the blade shaft protudes enough for you to install the wing nut.

Screw the wing nut ANTI-CLOCKWISE to secure the blades to the plastic base.

Do not over tighten the wing nut; you may have to replace your jug again at some point.

I did the same thing. Order parts at thegourmetdepotco.com -- This problem is caused when you put the rubber gasket underneath the blade instead of above it. This causes two problems: 1. It lifts the teeth on the jar away from the teeth on the drive gear, which can grind down and break off the teeth, and 2. If the drive gear contacts the rubber gasket, it will melt the rim of the drive gear. In the future, to reassemble the jar after cleaning, first put the rubber gasket on the jar, then the blade, lastly screw on the base ring.