Frank Swygert
Well-Known Member
Tow rating for the 2007 Expedition EL is 6,000#, 4x2 or 4x4. With the HD tow package it's 9000# 4x2, 8750# 4x4 (due to weight of 4x4 equipment). That means your trailer should weight no more than 5,000# at the max!! You have a little "wiggle room" with the max tow rating, but remember, the rating includes the load in the vehicle and the trailer. Even if you travel light (no fresh water in the tank, for example) you will have at least 1000# with passengers and luggage, maybe more.
You can upgrade your truck fairly easy to tow another 1000# (7000# total). Add a transmission cooler, or a larger transmission cooler if one is present (I'm not sure the standard model has one). That's been done with trucks for ages! To get the 9000# capacity you would need to change the gear in the rear from the current 3.31 to the tow package 3.73. I don't know if the rear springs were rated higher in the tow package or not. You can get Sumo spring boosters if necessary. These are just a rubber piece that goes between two of the coils in the rear springs. Without a load they really don't do much, but when you load the rear the springs compress more, and the rubber insert prevents them from compressing as much. Also, use a weight distributing hitch.
Other than the larger trans cooler and lower rear gear the tow package just consisted of a Class III hitch and 7 pin trailer connector. It's fairly easy to upgrade the connector, but you will have to run a couple wires from the front of the truck to the back, at least one from the battery. You can get a kit for this from most hitch stores. You can use any brake controller, but they can be unsightly. I used a Hopkins Insight partially hidden controller in my 2005 -- there are better ones now, like a Redarc or Curt 51170... but they cost a bit more. If those had been available a few years ago when I installed mine I may have gone for the few extra bucks. Happy with my Insight though.
You can upgrade your truck fairly easy to tow another 1000# (7000# total). Add a transmission cooler, or a larger transmission cooler if one is present (I'm not sure the standard model has one). That's been done with trucks for ages! To get the 9000# capacity you would need to change the gear in the rear from the current 3.31 to the tow package 3.73. I don't know if the rear springs were rated higher in the tow package or not. You can get Sumo spring boosters if necessary. These are just a rubber piece that goes between two of the coils in the rear springs. Without a load they really don't do much, but when you load the rear the springs compress more, and the rubber insert prevents them from compressing as much. Also, use a weight distributing hitch.
Other than the larger trans cooler and lower rear gear the tow package just consisted of a Class III hitch and 7 pin trailer connector. It's fairly easy to upgrade the connector, but you will have to run a couple wires from the front of the truck to the back, at least one from the battery. You can get a kit for this from most hitch stores. You can use any brake controller, but they can be unsightly. I used a Hopkins Insight partially hidden controller in my 2005 -- there are better ones now, like a Redarc or Curt 51170... but they cost a bit more. If those had been available a few years ago when I installed mine I may have gone for the few extra bucks. Happy with my Insight though.
