Just 4 days ago I installed a 22 inch light bar in my lower grille… now my mpg has dropped 3 miles since I did. Is this the cause of the problem or has anyone had this happen?

 

Give it some time before you start jumping to conclusions lol

4 days ain't much

 

Yes but I am still worried because I've only drove it 3 out of the 4 days lol I read somewhere it could be blocking the transmission cooler

 

Something else is going on because its not the lights. This does not increase frontal area therefore it does not add any drag. If you put the lights above the cab or below the front air dam then it would have an effect.

Jk