351CJ said:Go with 3.73's if you have an auto.
If you have a manual, go with 4.10s.
3.31 to 3.73 = 12.7% increase
3.55 to 4.10 = 15.5% increase
So the % increase will be similar.
Also keep in mind the OD ratio on the Auto is .71, while the manual has a .62 OD ratio.
3.73 x .71 = 2.65
4.10 x .62 = 2.54
So an auto with 3.73s will be pulling more RPMs on the highway than a manual with 4.10s
So it looks like you'd be pulling around 2500rpm at 75mph in a manual GT with 4.10 gears. That's not bad considering...