I'm looking at replacing my rear wheel bearings sometime in the next ...few months...ha ha and I'm looking at mazdatrix and also ReSpeed. Is the bearing collar the same thing as ReSpeed's retainer plate?

"Laser cut from USA steel and powder coated black. These plates are 1/4" steel and will better secure the axle bearing within the housing than the stock pieces."

is it worth it?

 

Different parts. The bearing collar is pressed onto the axle after the new bearing is, to help hold it in place. The part respeed makes is the metal plate taht goes on the outside and actually bolts the axle in. Unless your brake backing plates have rusted away there is no need, I think respeed has made them more for those of us who plan on buying the 5 lug axles he is selling to do a second gen brake conversion.

 

In racing applications we have seen the axles slide out of the bearings slightly. We solved this by using lock tight when pressing the bearings on the axles. The next place for the axle to put stress is the stamped steel retainer plates that are stock. Our plates replace the stock parts with a stronger, thicker part. Can be used with or without the stock backing plates and with or without the stock axles.

-billy