Here's what's inside an automatic transmission and how it works!




This transmission is from the RWD G35. All of its internal components are located along one axis, with no countershafts, since this is mounted longitudinally.




This is the transmission pump:


The first planetary gear set on the input shaft:


The first two sun gears:



The clutch packs that lock up the gear sets:



The brain (valve body), computer and solenoids that control hydraulic flow to the clutches:



This is the output shaft with the lock gear that the pawl locks into when you put it into park:



And that's pretty much all the components in an automatic transmission!







Enjoy!

 

Very nice work. I really enjoy these tear-down threads of yours. The pictorial information is very valuable reference.

 

Cool to see the 03' transmission apart. I haven't seen the external TCM valvebody until now. Nice to know they used aluminum high drums from the start also.

Thanks!

 

Thanks, glad you enjoy them. The video is much more detailed with explanation too.

Yep! This one is actually a 2004 G35, but same deal. I was surprised at the electronics in the valve body too - all the solenoids are easy to access from underneath the car.

 

I forgot the 04' RWD cars came with external TCM and narrow band upstream O2's. The 04' G35x got all the newer stuff. (widebands and internal TCM)