MPG when towing

[tatariley]

I towed my trailer last week with my mule that weighs 1800 lbs and was getting around 13-14mpg. Yesterday and today I was towing the same trailer with a couch on it (no mule) and was getting around 7-8 Mpg. Does anybody what would cause this? I literally wasn’t able to make a 2-1/2 hour trip without filling up again!!
Once I remove the trailer, I was getting my normal 22 miles per gallon

 

[JasonH]

Aerodynamic resistance is the biggest factor when towing. If you used the same trailer and your mpg dropped, either you drove faster, or the wind was against you.

 

[MAC1]

If you are getting 22mpg, that is fantastic, I usually get 16-17mpg without my trailer. When towing my 24' enclosed ATC aluminum race trailer, I get only 9-10mpg. Loaded trailer and car weigh approx. 7200lbs.