Are All Trasmission Fluids Created Equal?

A high quality synthetic like Amsoil will provide excellent service. If your rig has over 70,000 then drain and fill with regular fluid. Drive a hundred miles then drain and fill with Amsoil. The first change is to allow the detergents in the new fluid to loosen gunk. Draining will get that gunk out so you can start fresh.

OOPS....I'm not talking about completely changing...just to get a bottle to have with me in case I need to add.

Go to your local auto parts store and buy a quart of Motorcraft fluid that matches the transmissions requirements.
But since you have a 2000 vintage MH it is probably beyond time for a transmission service unless you have recently done it.

Just looked this up. 4R100 from 1998-2005 calls for Mercon-V per Ford's chart.

To be Mercon-V certified, it must be a quality synthetic. In this case, there really is no reason not to use the low-cost store brands.

I treat my transmission harder than anybody else on here I suspect. I use the cheap stuff. I also installed a Magnefine inline fluid filter, which means I don't need to drop the pan to change the fluid. I just point the cooler hose into a bucket, run the motor for a few seconds until I get about 6 qts in the bucket, and repeat two more times. I do this every 100,000 miles.

just looking at the F service guide under severe duty & it say no tran service on E 40 D which u should have in a 2000. severe duty consist of high speed (ha ha) towing or carrying heavy loads thats us.

Sorry just read where the E40D went out in 98 or 99 so u do have the 4r 100, so not sure abt ur sevice time

You should NEVER add anything before talking to your locale FORD dealers' service department! There is a lot of difference in Transmission fluids!