NEGATIVE....the 3.08 will NOT WORK as a 5 speed with a .72 s10 T5. Putting the T5 in 5th gear drops your rpms too low in the torque curve. You have to be cruising at almost 80 mph to get your rpms up where your vacuum comes up to a decent level and you can maintain your ground speed. As I tried to explain.....I went with a 3.08 with a 28" tire and the OD was useless. Even with the 3.42 you are running 70 mph at 2000 rpms and are still below the optimum rpm to maxiximize engine performance. I happen to live on the Ridge....a hilly backbone that runs north and south for about 100 miles in the center of the state and although it's not the Rockies, the 3.42 has to work unless you are running at 70-75 mph. Being that most driving in a straight axle truck, is more comfortable (and legal) at 55-65 mph I would adamantly recommend no lower than a 3.50 with a 3.73 being the best choice.
A 3.08 diff might be a viable alternative if you were running a .86 OD T5 but it will be VIRTUALLY USELESS as an overdrive transmission behind a .72 T5. I have an IROC-Z 3.08 posi/disc gathering dust as proof.
Dave
carefull everybody DAVE is the man, he knows it all i was just joking i didnt put 3.08's in with my t5. how could i dare????? honestly i'm just lonely and i have nothing better to do with my time then sit at home and lye about gear ratios in a message board =)
