do our trannies have an "overdrive" i know that we have lockup torque converters that enagae in third and fourth.

I've seen a couple of installs where overdrive units have been bolted to existing transmissions. Can this be done to our tls.

 

Yes, 4th gear is overdrive.

 

so is there any way of lowering engine rpms from existing levels. For example, right now the engine spins close to 3000 rpms at 80mph. Is there any where to lower this speed i.e. make 4th gear taller or something?

 

just curious.....which engine do you have? before tune-up, which is tomorrow, my 2.5 runs 3k at 70'ish or so. do you have 3.2?

 

96 3.2 - 3000 rpms equates to about 82 mph. 2200 is about 60mph.

 

Short of having someone make you a custom transmission with gears you select, no.

 

last few ?s is the rls (1st gen) tranny geared lower than ours. And engine output does not affect the rpms at which an engine will spin at a given speed i.e. type II conversion for example will not lower engine rmps at a given speed.

Thanks for all the input

 

RL has the same EXACT unit as the 3.2 trannies. Same ratios, same final drive. So if your tranny ever goes.. you can get a '96 - '04 RL tranny as a replacement.

As for the Type II swap, no it wont affect RPM's. Gear ratios stay constant.