is there any diffrence between the 3 and 3.5lt auto box in a 3rd gen?
i'm told it's a direct bolt on but will the 3.5lt TCU work with the 3lt box?
are the ratio's the same?

im under the impression that they are bolt on. However, the 3.5L box has a taller first gear. Putting a 3.0L box on a 3.5L will work, but 1st gear will be shorter. :)

Depending on where you are, you could drop around and we can compare the pin outs on the plugs. I am 99% sure they will work ok.

just north of melb near seymour.
the box is still in the car atm.
from everything i have read/looked at the boxes seem the same.

the manual lists diffrent speeds for the gears between the 3 and 3.5 but i'm thinking that would just be because of the diffrent motors?

surely if the manual boxes are a straight swap the bolts on the autos will line straight up as well. i cant see them being different as many people here have done manual conversions on a 3.5l whilst using a 3l box (me included)

but as far as the auto boxes being interchangable besides the bolts i dunno

EDIT: Ignore me

acording to the service manual the 2 boxes do have different ratios

Gear 6G72 6G74
1st 2.849 3.036
2nd 1.499 1.597
3rd 1.002 1.068
4th 0.733 0.781
R 3.735 3.274

had the 3lt box put in on friday been driving it around all w'end now.
direct swap both with electrics and mounts.
slightly different shift points but so far so good.

out of curiosity.. does it seem a bit more willing to turn the tyres off the line in 1st?? the differing ratio's seem to make me think that it would liven up the 3.5 a little..

had the 3lt box put in on friday been driving it around all w'end now.
direct swap both with electrics and mounts.
slightly different shift points but so far so good.

With the 3lt. torque converter having a slightly higher stall speed, have you noticed any difference taking off etc?

car is more inclined to spin taking off in 1st but i don't think 2nd and 3rd have as much get up and go as the 3.5