C4 automatic - replace with AOD or 5 speed manual

[hybrid]

Ryan, the AODE is a much stronger box. Because it's electronic, you can easily tweak the shift points yourself.
In my opinion, the only reason to choose AOD over AODE is if you don't want any electronics.

The AOD was designed during the 1980's "fuel crisis" when people were worried about fuel economy. For this reason, in stock form it's a pretty lazy gearbox. You'll either need an aftermarket valve body, or modify the existing one to wake it up.

I'm not a 4R70W expert, but I can explain the AOD lock up. With the the AOD lock up converter, the smaller centre input shaft engages in a spline that is DIRECTLY attached to the front of the converter. So when the gearbox engages 3rd gear, it essentially attaches the engine directly to the driveline, with ZERO converter slip. 4th gear uses the same shaft and is just the "overdrive" band clamping a drum to change the output ratio.
For the AOD, you can purchase non-locking torque converters (which I just put in mine) where the inner spline that would normally be welded to the converter shell is instead attached to the turbine with the rest of the shafts. So in 3rd and 4th, you still have converter slip like all the other gears. Your fuel economy will not be as good, but you get the full benefit of torque multiplication from the converter like any other gear. The shifts into 3rd and 4th are also much smoother because of the slip.

So you don't lose any of the gears by using a non-lockup converter - you just don't have the fully locked situation any more, which unless you're worried about fuel economy or the fact that you will do a few hundred more RPM on the highway, is not really a down side.

[rkmiller73]

Thanks Hybrid!

That is the best explanation I have seen on my internet searches.

I like to research stuff for a while - sometimes think it over for a year before actually doing a big change like this.

Informed decisions are usually the best.

[hybrid]

Absolutely... it's a shame you are on the other side of the world or you could come for a drive in mine to get a feel for what to expect.
The converter has changed the feel of the box completely, and I would now recommend non-lockup to every AOD owner except if your car was a daily driver and you did lots of highway driving.

[Dwayne]

Do all the AOD and AOD-E boxes work on the old Windsor's, or are there certain ones to avoid?