Gents,

I'm doing my usual post-event inspection and found the front seal of my rear end leaking. Searching "pinion seal" didn't provide much ACCEPT that I need to get the parts from Mazda. The Workshop Manual calls it the Companion Flange seal and a cursory read through of that section looks like it's rocket science. If all I want to do is replace the seal, do I have to deal with determining preload?

Any advice would be greatly appreciated,

 

Yes. If it's a track car, remove the damper while the flange is off.

 

Sir,

Yes, it's my HPDE car. I've got the Workshop Manual open and I don't see "damper" in the parts list.

Thanks for the quick reply,

 

damper or clover.

https://www.diyautotune.com/support/...lover-removal/

 

What's the consensus on removing those from a street-driven car?

 

So the gist I'm getting from reading the DIY article is that whomever wrote it didn't bother with preload or even torquing the nut with a torque wrench. Whether or not I remove the clover is secondary to my leaky seal issue. However, the google machine provided some more insight this morning indicating just tightening the nut down with an impact driver is not the way to go.

Has anyone here actually replaced the seal with the diff still on the car?

Thanks,

 

You can do it in the car, but when it leaks or the diff comes apart because you didn't take the proper steps, you'll be doing more work. Drop the diff and save yourself a headache. You will need to check the pinion depth and set the preload on diff if you're changing the seal. If you've read through the manual and don't understand it then you have three options:
1. Try it yourself and hope for the best
2. Find a friend who does know how to rebuild diff w/ proper tools
3. Take it to a trusted shop.

 

I marked the position of the nut and flange, so when I re-installed everything, at least the nut was in the same position. (I did not remove the seal, just took the flange off)

Does this mean it's perfect? Probably not, but I saw other videos suggesting that this was an acceptable method (not Miata).

I don't notice any differences after doing this, but I probably have less than 2500 miles on it.

BTW, that nut was tight. I had to use a big impact wrench to get it off, but used a conventional wrench with 3' handle extension to torque the mother.

 

Gents,

Thanks for all the inputs. I contacted two Spec Miata guys. Both gave identical replies. "Mark the flange and the nut, and put the nut back to exactly where it was before. And use Red Loctite". One added "It's the wrong way to do it, but I've done it about 800 times..." I put over 700 miles on her this weekend. I towed my HF trailer to VIR and did thirteen 25 minute sessions. I have no new sounds and don't notice anything feeling different.

 

Ditto above. I marked the nut with a sharpie, replaced seal and let her eat. Diff gave me no problems (even at the drag strip with 1.6-1.7 60's).