I have to say i'm impressed with my 2012 Limited EL when it comes to towing, I tow A LOT for business and pleasure (18ft car/equipment trailer & 24ft pontoon) I traded my 07 suburban back in April 1st thing I noticed was how well it tows (i've pulled as much as 11,300lbs with it) never broke a sweat!

like the OP stated it does sag I dont have the air ride either I wanted it but could not find one within 500 miles any way the coil over shock does suck when it comes to beefing it up for towing I have not found any thing was thinking of adding the factory rear Air ride and run it from a after market air source I'm very interested in seeing how you like that coil Sumo spring

I have a weight distributing set up but its a PITA so I dont use it only used it twice in 3 years

 

When I get the Sumosprings, I'll let you know how they are. I could really kick myself for not getting the factory load leveling. If the EL is still available in the next gen Expedition with the 3.5L EcoBoost and load leveling suspension, I'll be first in line to trade this one in.

What kind of weight distributing hitch are you using? The dealer threw in an "Equalizer" brand hitch when I bought my travel trailer. It seems to work better than the old EAZ-LIFT set-up I used many years ago and it's relatively easy to hitch up. I put the trailer down on the ball, latch it, crank it back up until the arms slide over easily, clamp them down, drop the jack and that's it. The travel trailer has a powered jack, that does make it easier. If I had to use a manual jack, it would be a PITA but not so much I would not use it.

 

I only have mince since April but if a EcoBoost EL hits the street I'll order one the next day! with the load leveling this time lol

I told the dealer to fine the same one I bought with the Air ride he could not find so I told him I'm going to order one he dropped his asking price another $1700 for a total of $9600 of sicker and then offered $1200 more on my trade at that point it seamed to good not to buy but feel kinda stupid now, If I knew there was no aftermarket air bag kit then I would of held off and got one with it the factory load level system

my weight distributing hitch I'm sorry I dont remember the name of it I really did only use it 2 or 3 times the 1st week and have not touched it since

 

I did finally add the SumoSprings and they seemed to make a big difference. Less squat, less sway and smoother ride. For the price, they were a great addition.

 

NPL,

Not the most current post, but I'm finding myself in the same situation as yourself, not with a travel trailer, but with the car trailer, the back of my expedition is always lower than i would like.

it tows great, but with the trailer loaded down it really rides like poop in the back if you have any significant tongue weight.

I'm considering the sumo springs for mine (2006) but i'm concerned about the ride when unloaded, and if they affect the ride height with no load.

how do you like yours when not towing?

 

I replaced the rear struts awhile back before I installed the sumosprings. That helped the ride & handling when towing and unloaded. Then after I installed the sumosprings, with or without a load, it rides better than it did before I put them in. It also did not affect the ride height when unloaded.

 

I've tried to improve my 2007 expedition for towing too. I have the HD tow package and I have over 11,000 miles of towing my 31't travel trailer. I've weighed it at #5,500 loaded, so much lighter than your setup. My TT is also a lower profile TT so I have less frontal wind area.
Your GCVW is 15,000# and you really shouldn't exceed that. If you ever get in an accident and there's a fatality and you're overloaded , I've heard your insurance may walk away from you and you could be on the hook for manslaughter. I intentionally sized my TT to be about 2K under my max weight so I wasn't overloading the vehicle. Its not much fun to be a the limit of your TV going up mountains. Remember you loose about 2% performance every 1000 ft above sea level.
My recommendations would be to get an engine monitor that will tell you your digital engine temperature and transmission temperature. I have a now discontinued MSD dashawk, but it gives crucial information on your temps. I've towed in 115deg heat in AZ and knew when to slow down. I think there are some that use a Bluetooth to OBD dongle and you can use your phone to monitor. I've given up on my pursuit of a larger tranny cooler, no one makes one. Dorman makes an equivalent HD tranny cooler which is great for non factory HD tranny cooler upgrades. I wish they'd make one with larger rows, and so do people on the F150 Raptor forums, but we both have as large as anyone makes. After 2007, the HD tow package did not increase the size of the tranny cooler so apparently Ford thought 2007 was oversized (good for us first years') Even in the worse of my conditions, the cooling fan rarely kicks in fully.. I think it engages fully at about 220F. Tranny may go up to 230 for a short while, and drops quickly going down hill. From what I've researched, these tranny's operate at a much higher sustained temperature and 220 for a short time is not too hot.
Make sure you have not only good load equalizing hitch, but also sway control. I made my first tow with a crappy friction sway control, then upgraded to a Reese Dual Cam sway control with load equalizing integrated.... works sweet with never a problem. The rear end already has synthetic lubricant and so does they tranny. There's an integrated PS cooler as well. If you haven't changed the spark plugs that is something you should do as they have issues before the 100K planned service.
I have posted my towing temperatures in this forum that you can search for. This is a great tow vehicle, but it's still only 365 ft/s torque don't have unrealistic expectations. The 6 speed transmission really helps over the 4 speed.

 

I just traded my 2010 Expy EL EB no load level on a 2014 Expy EL Limited 4x4 with load level. No very pleased with the load level because it complicates the set-up and seems unload the front axel (see my post on Disable load level).
Using a Reese dual cam weight dist. hitch on my 2010 Expy, I was able to adjust it to 1/2" squat and to within 1/8" front unloaded height. It took some work and alot of reading the trailering formums, but once adjusted it did not need any boost.

I had a Ford dealer install their aux. tranny cooler and also installed a ScanGuageII to monitor transmission fluid temperature. My trailer is about 7,000# loaded, and tranny temps through the Blue Ridge mountains climbed to about 225.

 

As far as anti-sway control and load equalizing there is no better hitch than the Hensley Arrow,in my opinion...check out their website...They are expensive,but worth every penny...I tow a 2014 Jayco 267 BHS with my 2008 Expy with the 6 speed trans and 3:31 gears...I haven't weighed the setup empty but I'm sure I'm on the edge....I tow in 5th gear,70mph,and 3000 rpm's with ease...My temps are monitored by a SCANGAUGE II..I look at Trans,ECT and Cyl Head temps and on level ground the temps are pretty much within what I consider normal range..If I'm up and down hills,especially long grades,I don't try to maintain the speed limit..I let the truck work without "crowding" it...Oh,and I also have a SCT Tuner from 5 Star with a custom tune and a AirRaid cold air intake...Contrary to popular belief,It DID make a huge difference,although the CAI drone can be annoying..

 

It is very interesting to hear of your experience with the Hensley hitch. I have considered this one, but have concern over its considerable weight. If you check the weight limits on your hitch (bottom near the receiver) you may be in for a surprise. Maximum tongue weight on my 2010 Expy was 910# with weight distribution.
I invested in a tongue weight scale and found mine to be 1000# (approx. loaded weight of trailer, with full propane and 10 gal. freshwater, 6800#). Adding the Hensley (which I believe weighs over 100#) would certainly stretch that limit.
There is no doubt in my mind that the Hensley or ProPride system are excellent, but I have concerns about safety with the receiver hitch weight limits.
BTW, since my trailer is a rear living room, I repacked it to shift weight from the tongue towards the rear to reduce that weight.

 

I have a 2004 Expedition XLT with HD Tow. We tow a travel trailer with a GVWR of 5995#. Don't know what it is loaded yet as it is new. Have a full load of kids in car and one in back seat with 2 dogs.

The rear end sags. Trailer dealer set up Equalizer hitch for us but wondering if they didn't do it properly. Going to have it checked out by a hitch place next time we hook up trailer. Anyways, wondering how to beef up suspension and I am not having good luck. Expo has coil over shock. So far it seems the recommendation is to go with SumoSprings?

Please explain to me exactly what I need to buy and tell mechanic. I am a female non-car enthusiast.

 

In my opinion you should not need any suspension modifications with that weight. A properly adjusted weight distributing hitch should level out the tow vehicle (TV).
There are lots of threads on the internet about setting up wd hitches, but I would have to know which brand and model you are using before suggesting a site. Alternatively you could search "setting up a xxxxx hitch" where xxxxx is the brand of your hitch.
I have been towing with an Expy XL for five years and have not had to modify or supplement the suspension. My TT weighs in at 7,000 pounds loaded and I use a Reese Dual Cam wd hitch. Several factors apply to proper adjustment and it might take a few adjustments before you get it tuned in perfectly.
Most important though is to be safe and not tow with the nose of your TV pointed toward the sky.

 

I'll post a quick response and if you need more info let me know.

Yes you should switch to E tires, I'm running 285/55R20 Michelin LTX AT2s with a rating of 3,300 lbs, well over any load I might put on them in a 1/2 chassis.

Yes you should add a cooler. I don't tow heavy with this expedition but if I were I would look hard at a AFE deep pan as well as a nice oil cooler and transmission oil cooler combo especially looking at your location where even the devil seeks shade in the summer. I would also ditch the current fluid and swap in some amsoil, there are lots of people with 6R80s who notice an improvement in the better fluid.

Below is a link to the cooler I run on my sliverado, it's well over 450 hp and towing 8,500 lbs even in west texas I have yet to see trans temps hit 190. I'm running both my engine oil and trans fluid through this with a separate OEM powersteering cooler.

Maxi-Cool HD Cooler Coil & Electric Fan Assembly

Lastly you can add the 2014+ factory springs and load leveling shocks for under 800 bucks using all oem parts. These are a direct swap in and would look and operate in a OEM fashion. If you need a parts list PM me your e mail and I'll send over the complete list with part numbers.

 

I'm interested in the suspension swap you are talking about.

Do the 2014+ use a coil over air strut? That's what I've been wanting for my 2006. The sumo coil springs help, but not as much as I had hoped

 

The 2006 doesn't take the same shocks as the 07+. Also no, the 2014+ are no longer air since ford is too stupid to get that right. They use an outsourced hydraulic shock that uses road motion to pressurize the system and maintain a reasonable ride height. I have not been able to confirm that Nivomat makes them for ford but it sure looks like it.