Broken Hydraulic Piston on the Valve Body for A442F Auto Box

[Frazer Small]

Thanks for allowing me to join Crispin. I am South African and live in Uganda. I have an 80 series auto transmission Land Cruiser imported from the UK. I am busy rebuilding the transmission, it's an A442F box and it was struggling to find reverse when cold and jumped between gears moving forward. Works okay when warm but not perfect.

When I removed the Valve Body an end piece of one of the hydraulic pistons fell out ( it seems like it sheared off). I have attached some pics here for clarity.

My question is. Are there any auto box guru's here that can explain what might cause this and what purpose this particular hydraulic piston serves? Also. I have a second hand Valve Body which I intend using the intact hydraulic piston on this one to replace the broken on. Any tips on how to remove these hydraulic pistons? Look forward to discussing this further....

Blue arrow on two of the pics shows the location of the broken piston.

Other than that the box seems in great condition.

Thanks.

 

[Michael80]

Hi Frazer,
I have used a company called JPAT transmissions before, always found the very helpful and a very good website.
They have a full manual with part numbers etc for the A442F.
I’m unsure but it looks like a valve for diverting oil controlled by the solenoid valves.
Cheers

 

[Frazer Small]

Hi Frazer,
I have used a company called JPAT transmissions before, always found the very helpful and a very good website.
They have a full manual with part numbers etc for the A442F.
I’m unsure but it looks like a valve for diverting oil controlled by the solenoid valves.
Cheers

I'll check them out. Thanks.