1999 Exp EB miss/hesitation at 40-50mph

My expedition misses only when driving around 40 or 50 mph. The vehicle vibrates or shakes then if I stomp the gas it goes away. I replaced the spark plugs before this happened. I used Autolite Platinum plugs. Anyone have this same problem? Do you think it can be the plugs are bad and I should replace them with Motorcraft plugs?
Thanks

Does the "miss" occur right at shift point into high gear? If so, it is more than likely torque converter shudder. Let us know.

When I take off you feel a slight miss from take off, real light. As I go faster it the miss is there. Only when going around 40 - 50 mph is when the truck hesitates hard or shakes. I hope this describes it a little better. Thanks for the response.

Have you checked for any DTCs - Diagnostic Trouble Codes?

Even if your Check Engine Light is not on, you may have a code in the computer.

BTW, what size is your engine?

Autozone will provide a check on your OBDII system for you. If you do not have a code scanner.

Autolite plugs are the same as Motorcraft. Just make sure they are double platinums.

I could also be tranny related too, but check for codes in the mean time.

I d put some motorcraft plugs in it. Ford engines are sensitive in relation to ignition parts. Make sure they re gapped within specs.

I got a engine code to come on tonight. I will have it checked tomorrow. I'll also update tomorrow. Thanks for the replies.

The code was a 301. I checked the coil and it was bad. Replaced it and now the truck runs smooth. Thanks for all the help and replies.