I am pretty sure my 97 K1500 with 5.7L has the 4L60E tranny. On the very bottom of the tranny, forward of the pan is a hole, about 3/4" in diameter, not threaded. I am guessing there is something that is supposed to be in there? Does anybody know what should be?

 

I think that is an inspection hole. If it is what I'm thinking, it normally has a sheetmetal disc that is held in place by tabs...

 

Thanks for the input. My only worry is it is important, and the local chevy parts department guy did not have a clue. Anybody else have any ideas? I am thinking this might be why there is a sound of air being forced out somewhere, but only when it is in gear and on the accelerator is it extremely noticeable. I know I have a bad exhaust gasket(replacing this weekend), but I'm thinking that is not it because it only happens when in gear. I can sit in park and rev the hell out of it and not have any of that sound. Does anybody know where I can find what is supposed to go there? I looked at pictures of the tranny, but cannot find 1 from the underside.

 

Its the exhaust, its just more noticable when there is an actual load on the engine, which is increasing the exhaust back-pressure, forcing more air thru the leak.

 

I THINK MISSOURI DIRT IS CORRECT...TRANS' HAVE AN INSPECTION HOLE IN THE BOTTOM OF THE BELL HOPUSING...ABOUT AS BIG AS A SKOAL CAN...PROBABLY THE TIN SHIELD FELL OUT

 

Alright, I'll check that info out when I can. It's only about 3/4" or 1" or so. Thank you for the input, I'll let you all know if that is it. I just got her back from the muffler shop, now have true dual super 40s, sounds bad *** in higher rpm, noticeable increase in throttle response.

 

YES,2 HOLES..ONE SKOAL CAN SIZED,1 ABOUT CANDY CANE SIZED..BOTH SHOULD HAVE TIN PLATES OVER EM...QUITE A FEW ARE MISSING

 

+1 for what argon posted above. Changed the oil in mine today and checked out the bottom side of my rig. I thought about this post when I noticed that there are actually two different holes. Cover missing off of it shouldn't be a problem...