MDX is comparable to Jeep Grand Cherokee, X5 and such, right? I think they all have similar wheelbase.
There is the towing capacity. And there is also the loading capacity of MDX, which I was not able to find from my brief search. These two are related but are two separate things.
Curb weight of MDX is 4600 pounds
Towing capacity is 5000 pounds.
Loading capacity is 1500
pounds (?, my guess)
a) 2 adults + 3 children + luggage + full tank of gas = 800 ~ 1000 pounds?
b) tongue weight of Flying Cloud = 12, 13% of 4200 (empty) or 5000 (loaded) = about 500 ~ 600 pounds
a + b must be below the "loading capacity (1500, in this case)
You can see how what you are proposing may be beyond the limit or really close to it.
Having said that, I may still go for the combination, if I carefully study the specs, improve the factors, and weigh pros & cons (Is switching to new and bigger SUV practical? Do you want to drive bigger SUV as your daily driver? How often do you plan to tow your trailer? Up and down the mountains? Bicycles or extra activity gears for the children? Family safety?)
I imagine I would:
- Upgrade the tires to LT rated (?) or something with stiff side-walls and higher pressures
- Install additional airbag suspensions in the rear coils
- Reinforce the hitch by welding additional steel members under the chassis in the rear (HitchMasters in VanNuys can do it). Wait, MDX has unibody chassis with no ladder frames, I don't know if this is even possible or practical.
- Investing in Hensley or ProRide hitch can greatly reduce the risks for swaying or out of control situations.
- nice brake controller (I like Prodigy)
These are the things which quickly come to my mind that you can (or need to) do to make MDX a better towing vehicle.
By the way, V6 engine on MDX gives you 300 hp / 275 pounds torque. When you approach the hills to Camarillo on 101, or Tejon Pass on 5, you would need to climb really slowly (like under 35 mph or even 25 mph) Nothing wrong with this. That's how truckers do it when hauling full cargo. Watch out for the rise of transmission temperature.
- Install transmission temperature sensor, if you don't have one. (This is when MDX is at disadvantage. It's not a common American truck)
I used to briefly tow 28' International (empty at 5500 pounds) with Grand Cherokee V8 (+airbags, +hensley), and I managed it alright. But, after loading up with many extra stuff that is required or that you carry for extended travel/full-time lifestyle (me only), the trailer is now much more heavier. So I soon switched to a full-size American SUV with V8 and ladder frames.
Hope this helps.