I have a new '03 4Runner with the 5 speed auto tranny and the v8 engine. Under heavy acceleration, the tranny takes quite a while to shift. Does anyone know of shift kits or other ways to improve the shifting performance? I'm specifically concerned about how fast the transmission reacts once the AI has instructed it to shift as opposed to adjusting the AI. Adjusting the AI is another issue...

Thanks.

-tpg

 

Congrats on your new ride! If you just got it within the past week or two and are still driving gentle break-in miles, it could be an AI ECU learning issue. Resetting the engine ECU (by pulling the battery) can take several days to re-calibrate to your driving style. I'd guess the 5A/T could take even longer with AI. Just a guess though.

 

BT17R- Thanks for into info about resetting the AI ECU. I'm off my break in period, so now I can start driving it right.

I don't think its the AI because I can tell when the AI has instructed the tranny to shift. It's that "mushy" time in between gears. I guess the best examble is when the gas pedal is floored and its shifting between second and third. The shift seeems to take quite a while.

 

If your flooring the v8 (5spd) and are attempting to race it.. then i'd suggest u putting it in 3rd gear and try racing it. this way the gears should be smoother...

 

tpg, I understand what you're saying. The newer crop of Toyota/Lexus A/T's (I have two others in the garage now) have a shift shock softening feature. At the moment of up/down shift, the ECU instructs the torque converter to freewheel (as opposed to locked mode), retards the ignition to momentarily reduce power, accomplishes the shift, and then reverses the process. If you aren't used to it, things do seem to happen a bit slowly in the name of smoothness. However, your situation might be different but can't say b/c my '03 isn't here yet. I'll be looking for your symptom when I get it, but think it might be part of the newer trans characteristics.

Actually, the one concern I have about the new 5A/T is the change from a steel planetary gearset to aluminum. I wonder if they'll handle the added stress of the S/C (with 430 ft. / lbs. torque) that'll be installed after break-in. Oh well, warranty...