Having troubles with my new 4l60e in my camaro. It has been in the car for about 40 miles now, easy driving with a few hard short pulls. Bought it used and apparently it has been slightly built (not for sure) but does have a shift kit. I am using a circle d 4000 converter. I got into it pretty hard and around 4k rpms it felt like it slipped and hit the rev limiter. I drove the car easy where I was going. I had to give it a lot of throttle to make it move after turning or slowing down. Got the car there, and when I shut it off I heard the flywheel make some noise. Pulled the starter off and 2 of the converter bolts were loose. I tightened them up and took it for a test drive and it feels like the trans is in a bind. Reverse seems fine but when the car is in drive I have to give it a lot of throttle to make it move like the brake is on. It goes away and comes back intermittenly. Converter bolts are still tight so I'm stumped. Anyone have an idea what the problem could be before I take the trans back out? The safety loop bolts were loose as well, any way I could have thrown the pinion angle out of wack from that?

 

I would suggest hooking up a trans pressure gauge to see what the line pressure is, especially when it feels sluggish. I wonder if the converter got loose enough to damage the pump and give you pressure problems.
You can buy one on ebay for $45 (with shipping) or have a local trans shop check it out. The ebay ones have a 6 ft hose, long enough to hang from your outside mirror while you drive around.

If the trans acts up after hard cornering or braking, I would check the trans filter, making sure it is the right one and is seated snugly. Obviously check fluid level too with the engine running - should be right at the full line or less than 1/4" above it.
Having it slip around 4K RPM is a bad sign. Intermittent low line pressure (causing slippage) can also be caused by a sticky/defective EPC (pressure control solenoid).
, but good to check the fluid level, filter