Does anybody know what type of tranny a 81 Trans am that came from the factory with a 305 chevy should have? I'm positive it's the original motor and tranny. Just wondering if they all came with the super t-10 or not?

I thought ST-10s. Try a quick search at transamcountry.com. TMK, they were iron cases with steep 1st gears. But I could be misinformed, esp considering the 305 (which I didn't know was an option either).

Should be a Super-T10 iron case with a 3.42 first gear.

Super T-10's where used from 1975 through 1985 on most all GM's. T-10's where used until the mid 60's until the high horse power motors demanded a stronger Trans and that is where the muncie step in. The Muncie (M-20, M21 & M-22's) where the only 4-speeds used by GM. As smog engineering reduced horse power the T-10 with modifications now called the Super T-10 took over the 4-speed jobs in 1975 and then was followed by the Super T-10 with Overdrive.

I got one out of an 82 Firebird. It is a 3.42 low alum case.