Issue with car vibrating at 40-45 mph?

I have 2005 Ford Tarus with around 100,000 miles on it. I'm having an issue with vibration problems around the 40-45 mph on highway. I have had the struts and shocks replaced have purchased 4 new steel rims and purchased two sets of tires. The first set of tires I purchased were cooper tires and the dealer balanced them several times but they car would still vibrate. Assuming there maybe an issue with the tires I purchased 4 new Michelin tires same issue. I gave my mother the set of cooper tires and she had them put on her impala and her car rides smooth with them so now I'm wondering what could be causing my car to vibrate. I have had a road force balance done and four wheel alignment done at firestone and was advised the tires were fine. Any advise would be appreciated as I have no clue where to go from here.

A simple programmer for an 2001 Honda Accord?

I'm just wondering. I'm not a ricer, I just want to get a little more power out of a vehicle I may be getting. I know there are tuners you can plug in to the OBD2 port, and it reflashes the ECU. My dad has one for his 6.0L diesel Ford, and another guy I know has one for his mid 2000's Dodge Ram gasser. I looked around and can't find anything like this for an Accord. Do they not make them? Just a curiosity thing.

Added (1). Something I want to add. I'm mechanically inclined quite a bit. Is there any simple mods for these vehicles? It's the 2.3 Vtec engine. I was looking at camshafts mostly. Any other ideas?

How to unplug a car door actuator?

I have a 98 ford falcon and the central locking doesn't work, the locks automatically go down and up again. The same happens if I do it manually.

I think it is an actuator problem. How do I unplug the actuator so that I can manually lock the doors (I'm ok being able to just manually lock them so don't want to replace the actuators).

How to clean a cooling system inside an enging?

I've got a 1967 Ford Custom 500. I'm doing some slow work on it with some family and need to clean the cooling system inside the engine. Could you help me out please? Any description helps and a video would be really appreciated.

Why does Ford, Chevrolet and Dodge continue to market products to a customer base that no longer exists?

The automobile companies obviously are going to do whatever they're going to do…
But this is a philosophical question, and perhaps a sociological one as well…

Why would Ford, Chevrolet and Dodge bring back automobiles appealed to mostly working class teens back in the 1960s, 1970s and 1980s…
and to uneducated, poor white trash adult males who contributed to America's urban social problems on the streets…

When such people are no longer a viable customer base because of Government regulations and current day economics, pay structure and modern costs of an automobile?