Can a 4l80e or any E trans fluid level be checked on initial start without the TCU hooked up to it?

Other then being able to to go through the gears, could any damage be done by this?

Thanks

 

What is TCU <---??

 

Transmission control unit or computer.

 

Ok, maybe it should be called TCM.

 

It's not recommended because it will default the trans to max line pressure. I guess that could be a problem on a new trans if fluid hasn't circulated to everything yet.

I've never had a problem with anything like that. Like forgetting to plug it in, or an older trans forgetting the modulator vacuum line.