My Mazda 3's transmission has started to shift poorly
 

Car:
2007 Mazda 3 2.3
5 Spd Auto
63,000 miles

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Fairly recently, I want to say within the last 6 months I have noticed the transmission has lost some of its smoothness and has started making strange noises.

I started paying attention to the trans when it was still cold out and the 1 - 2 shift was very hard and abrupt until it got up to temp. To combat this I let the car warm up longer and drove it carefully before I hit the highway. Sometimes I would even release the gas right before the shift to mitigate the shift shock. Once the weather got warmer the 1 - 2 shift shock goes away after less than 5 minutes of driving.

About the noises. If I am driving at any speed and come off the gas, let the RPM's settle and come back on the gas I can hear the transmission thump. I can't feel the thump, just hear a very clear audible thump as soon as the RPM's come up. Its not loud almost can say its faint, but with the radio off it can be heard at 50 miles an hour.

About the smoothness. When accelerating with the engine under heavy load, either up a hill or accelerating at 3/4 or more throttle(worse with the AC on) the 3-4 and 4-5 shift will be very rough and abrupt. You can feel the shock in the drive train. Drive with less than half throttle and medium to low load and its more or less fine. Its not as smooth as my 2012 3, but its definitely not as smooth as it should be.

I am really starting to worry. The trans fluid is clean and pink. Smells fresh too. I added less than a 1/4 of a quart(got the fluid from mazda) when I bought the car in 2010.

I am thinking about taking it in for a proper flush, filter change and valve body cleaning but I don't know if its fluid related. Granted id rather pay 200 for this than 500+ for a new transmission w/labor.

What do you guys think?
Anyone familiar with any TSB's, maybe they updated the computer and I don't know about it?

Thanks.

Check the passenger side motor mount for your thump. Guaranteed it sprung a leak and lost all its "hydraulic" fluid.

yes swap juice why have you not done this yet

passenger side and rear mounts go and cause this issue, fix it soon than later to avoid blown out gears

Thanks for the tip. I will examine the motor mounts and report back.

Some googling confirms I may be fucked.

3-4 Shift Shock - Mazda 6 Forums : Mazda 6 Forum / Mazda Atenza Forum

2007 Mazda 3 Recalls and Technical Service Bulletins (TSB's) Provided by ALLDATAdiy.com
0501010 AUG 10 A/T - 3-4 Shift Shock Under Load

Is it to late to get this done even if I pay for it?

Transmission Jolt problem

And the TSB for the problem. I am going to check my Vin Tomorrow.
Mazda mazda 3 gt: i get a stuter between 3 and 4 gears auto,mazda - JustAnswer

Motor mounts are in excellent shape.

The reading I am doing is telling me this can be a very expensive repair. Never having worked on anything except rwd, anyone want to tell me how much harder a swap would be if I do it on some jack stands?