3RZ Swap Update in my LJ71 – Still Stuck with A343F Confusion (2 Viewers)

[rakan100]

This is a quick follow-up to my last post about swapping a 3RZ-FE into my Prado LJ71 (originally 2L-TE with A343F auto trans).


I’m still stuck. I used a manual 3RZ ECU and didn’t replace the transmission ECU. The car runs, but shifts feel off, torque is weak, and I don’t know what’s wrong exactly.
Biggest confusion now: is my A343F (from the old diesel setup) the same as the A343F used in petrol 3RZ/5VZ trucks? Do they have different valve bodies or electronics? No clear answers yet.

I’m still learning as I go. Any help from someone who’s done this before would mean a lot

 

[TheBussman]

i wouldn't expect that to work. an auto 3rz ecu should be pretty cheap.

 

[Malleus]

Mechanically, the transmission is designed to match the torque curve of the engine. IDK about the valve bodies and electronic controls. Possibly optimized for the engine curves, which would be different.

 

[rakan100]

Mechanically, the transmission is designed to match the torque curve of the engine. IDK about the valve bodies and electronic controls. Possibly optimized for the engine curves, which would be different.

You mean I should change the torque converter ?

 

[Malleus]

No

 

[cruisermatt]

You mean I should change the torque converter ?

Most likely yes. I would install a 3RZ version converter. It has a different part number compared to the LJ71 converter, and most likely has a different stall speed. Diesel converters are a lot tighter.

 

[rakan100]

Most likely yes. I would install a 3RZ version converter. It has a different part number compared to the LJ71 converter, and most likely has a different stall speed. Diesel converters are a lot tighter.

Thank you so much can you provide me the part number or which car donor i can take it from because in Saudi Arabia we don’t have tacoma or 4runner