Prior to a a 7k mi road trip, I replaced CV axles. On a test drive, the driver's side axle popped out (oops). I didn't know at the time it was leaking trans fluid thereafter. After reinstalling correctly we embarked on a 7k mi road trip. Smart!!

After about 1.5k mi, fuel mileage started to drop which I traced to a clogged fresh air inlet on the rear O2 sensor. Trans fluid leaks out despite having 3 new axle seals installed since.

It is very difficult to avoid clunking noises in between gear changes but it is possible. I replaced the dogbone / torque axis motor mount & driver's side transaxle mount. I think the center transaxle and timing chain cover area motor mounts are ok, and I think the clunk noise is in the trans.

As a temporary test, I bypassed the driver's side torque axis mount solid by welding metal between the frame of the dogbone mount and a washer which goes under one of the bolts that hold the transmission mount bracket to the trans. This was to test if stabilizing the transmission helped with the clunking - it does not. But, it does transmit a lot of sound information to the cabin now. I wonder if some internal trans bearings have been damaged from the initial low manual transmission fluid condition from my botched CV axle replacement.

Are any manual transmission parts diagrams & part numbers available? I would entertain removing the trans & replacing worn bearings found in a zealous, DIY teardown one day.

Engaging clutch from still with 1st gear selected: https://photos.app.goo.gl/S7L98t3pJoyq2y51A

Driving to 45mph through all gears with the solid mount (noisier than stock but gives more information): https://photos.app.goo.gl/oerF66NUoHwsDTeY9

 

Also, will the 6pd trans from the 2nd generation Fit fit?

 

Think this is worth a shot? https://www.bgprod.com/catalog/drive.../#bg-product-8

Also for reference, here are parts diagrams and part number listings for all things Honda (this is the transmission section): https://www.hfitinfo.com/hofi-993.html