A 2003 Subaru Outback is a really nice tow vehicle for a small to medium size popup without too much trouble. Larger popups are also towable if you know what you are doing. (Check my signature) The one real catch here is that you have to have trailer brakes for anything but the smallest of popups. This isn't Subaru's fault, they are just being more responsible than most by stating this up front rather than in tiny print at the bottom of a fancy brochure.
One nice thing about Subarus is that they are rated to pull their maximum capacity even with a full load inside the car. That is a departure from a lot of competing vehicles that advertise higher tow ratings, but ultimately end up towing less because they can never attain those ratings once everything placed in the car is deducted.
If you look for a popup with a dry weight around 1600-1800 pounds you are in the right ballpark for starters. After you load it with gear you will be near the 2400 rating. Lots of people will tell you bumping up against the rating is no good, but they aren't familiar with Subarus like I am.
As far as hitch weight is concerned, the published numbers are ALWAYS lower than actual. A far better way to figure tongue weight on a popup is to calculate 12% of the total, loaded, ready to travel weight. For example, a 2000 pound popup should have 240 pounds of tongue weight (coincidentally the rating of the Subaru OEM hitch). If the popup you want is under 2400 pounds, but carries a tongue weight over 240 you can upgrade the hitch to an aftermarket unit. The aftermarket units can carry 350 pounds of tongue weight.
Yes, I have electric trailer brakes. I wouldn't tow anything more than 1000 pounds without them anymore. Since my Subaru is our backup tow vehicle, our good brake controller is in the van. My old controller, (Tekonsha Voyager) is in the Subaru and works adequate for occasional towing needs. If I was towing more frequent with the Subaru, I would install a Tekonsha Prodigy instead. It's a decent mid-range brake controller that suits small tow vehicles and popups very nicely. Better brake controllers are out there, but for most popup owners they are just a little overkill.
My Forester (which will be very similar to your Outback as far as towing is concerned) pulls it's maximum 2400 pounds without even a struggle. I have a non-turbo 2.5 liter H4 model with a manual transmission. I can cruise down the freeway in 5th gear with a family of 4 and a black lab plus luggage while towing 100% of tow rating. Small hills do not require a downshift, larger ones pull in 4th and I've never dropped lower than that. Average towing mileage is low 20's. If your Outback has the H6, you have even more torque than mine and towing will be that much easier.
Good luck.
-Jimmy
'04 Ford Freestar (Primary tow vehicle) '05 Subaru Forester (Backup tow vehicle) '65 Bethany popup (best popups ever made!) Looking for a tow vehicle Minivan towing
Ditto to Caddy as I pull with a Forester, but I have had to go to second gear coming up the west side of the Rockies to the Eisenhower. If I am not mistaken, you also have a better torque to power profile in the older ones rather than the newer ones where they "fixed" everything so you could get on the highway rather than tow...
If you have an auto, you will also need a tranny cooler.
Caddywhompus ......my guess would have been just what you said
here. (Although I wouldn't have had a guess about tongue weight.)
I got this Subaru new, and it never fail to be amazed at how much
power it has for the size of the engine. Also, I've had it for 5 years and it's running as smooth now as it did when it was new.....and
when it was new, it was super-smooth.
I've thought about getting a Toyota Truck for a TV, but I know the truck would be parked all the time unless I was towing.
Your post was really helpful! Good to read your comments about Subaru too!