I know absolutely nothing about the E4OD trans and now I'm having issues with it grinding when going into park and having to push it to 3k to 4k rpm to get the truck to crawl any advice or solutions greatly appreciated

 

Take it to a local pro.

 

They want 1200 to look at it

 

Go somewhere else.

 

Grinding when going into park, unless the truck is moving, sounds like the problem is farther back in the drive train. What vehicle do you have? 2 wheel drive or 4 wheel drive? Do you have any mechanically inclined friends or relatives who live close?

 

Who's going to be moving when they go into park?

 

To answer your question, the output shaft of the transmission which contains the cogs that the parking pawl meshes with. After some grinding the parking pawl stops the output shaft from turning.

Here is the full explanation. The OP said he has to rev the engine to 3 or 4000 RPM to gat the truck to barely move. The transmission is OK but the problem is farther back in the drive train somewhere, so when the OP shifts back to park the output shaft of the transmission is still turning when normally it would stop when the truck stops moving, thus the grinding.

I can't guess what is wrong farther back in the drive train, but. If you have a better explanation of the grinding, I'll be glad to read it.

 

Sounds like a transmission issue to me.Everyone has their own interpretation of a grinding noise. The fact that the engine has to be revved so high to get the truck to move sounds more concerning to me and tells me of a torque conv. or pump/ pressure issue with the transmission. Any way with the vague information he provided, his best bet is to have a pro look at the transmission.We don't know how or what the transmission sounds like when putting into neutral? Did he lose forward and reverse, who knows? I doubt it is a simple repair.