Twice now in a year, a brand-new shifter boot seal has failed on me. This is the rubber seal with the 3-bolt flange on it that bolts into the top of the transmission tail housing.

What am I doing wrong? I am using redline MT90 oil ... maybe that is excessively corrosive? And there is a possibility that I have too much oil in the tail housing, and it is splashing up and making the seal fail prematurely. But I wanted to check with people's experience before I spend another $50 on this old jalopy.

 

that boot sucks and is prone to rip no matter what, you can use generic aftermarket miata boots for it, they may actually be better since they won't be 25 year old new old stock rubber parts that have been sitting on a shelf for decades.

 

How is it failing...tearing, turning to goo, what?

 

the miata does use the same boot. however nobody has had these on a shelf for 20 years, that just is not how the business works.

 

i kinda doubt mazda still produces most if any parts for the FC3S, that's why we call it 'new old stock'. i could be wrong in this particular case since it is very similar to the miata boot which was built for a bit longer than the FC.

almost anything you get from mazdatrix is old stuff.