Update : My 2018 Mazda 3 will need a brand new transmission


Feb 7, 2008
Good day folks,

After a few recent post about one Mazda dealership refusing to change my AFT fluid at 100 000 km (my car is now 130 000 km) and getting my transmission overfilled by another Mazda dealership after ATF change, now Mazda Canada concluded that I need a brand new transmission coming strait from Japan (that's what the dealership told me, from Japan).

Yesterday, I wanted a second opinion for my transmission problems because I don't trust any dealerships to maintain my car, so I did bring my car to a well known transmission shop that I knew was honest. There was no fault codes, none, but he noticed that the 3rd, 5th and reversed gear had a hard shift/down shift and was engaging hard in reverse. So he found a bulletin from Mazda with the exact issue, exact gears. So basically told me the dealership needed to reflash the computer. At that time, I was still waiting to hear from Mazda and I received a call few hours later saying they will replace the transmission completely.

I assume that those series of transmission had a manufacturing defect? They did tried everything, relearn, flash ECU, and it didnt do anything, stayed the same.

Now, my fear is that they replace the transmission and that other problems would popup afterwards, I don't know if I should keep it or get rid of it. Other than that, the car was great, only put new disks and pads on it with cabin and air filter, spark plugs. Flawless until this transmission issue. The rest of the car is very well maintained, undercoating every year, wheel alignment every year or two, tire rotation, oil change at 5k miles.

I'm asking you guys with you're experiences, is it worth it to keep it? or should I get rid of it?

Thanks guys.
New trans and drive it till it drops.
Mar 2, 2004
We had a Kia remanufacturered transmission put in our 2015 Sedona at 30k miles. It's been flawless since except a bonehead installer mistake which was semi-easily rectified.

The idiot installing the transmission used the wrong bolts (with different thread pitch) to attach the transmission mount (the one that goes from bottom of trans to subframe) and proceeded to strip all three threads in the transmission case completely. It held fine for about 500 miles or so, long enough that I couldn't take it back to dealer that did the work which was 2000 miles away. I started hearing and feeling a clunking when shifting into gear from Park, or between forward and reverse. It was easily diagnosed and I repaired it myself with some heli-coil thread inserts.

As others have said, a new unit would reset the clock on transmission longevity, but hopefully you get a capable installer.