Sizing Santa Fe and R-Pod 178

One other consideration in selecting a tow vehicle. No matter what you tow with you will get around 13-14 mpg because fuel consumption is dominated by trailer air drag. Less in the mountains going up and down grades. So, the small SUV's with 15-ish gallon fuel tanks don't really work well, you end up stopping for gas every 120 miles or so, and you better fill up before heading into a remote area or you might not get back. The Highlander tank is about 20 gal which gives you a practical range of about 200 miles. Big difference. I wouldn't want anything smaller than that. 

That's what I tow with. It is fine for the 179 including boondocking loads, but I wouldn't go any smaller on the tow vehicle or any larger on the trailer. You will still want a weight distribution hitch and antisway system. A 5000 lb rated Honda Pilot or other comparable mid-size SUV would also work. 

If you go the Highlander route be sure to confirm with the VIN that you are really getting a Highlander with the 5000 lb tow rating. Any Toyota parts dept can do that for you.  Not all 3.5 V6 Highlanders are rated for that. There is an additional oil cooler for one thing that you effectively cannot add aftermarket. 

So I think that vehicle is not quite up to the task.

So, my recommendation when looking at trailers and tow vehicles is to use the gross trailer weight (GTW), and forget the empty weight, particularly if you will be boondocking. The 178 has a gross trailer weight of 3795, essentially the same as mine and most of the mid sized rPods. 

In addition to staying within tow weight and tongue weight ratings, take a look at the max combined gross vehicle weight rating of the tow vehicle, should be on your driver door sticker. Then, take the GTW, add the curb weight of the TV, add 80 lbs for a weight distribution hitch (which you will want), add the weight of driver, passengers, and gear in the TV. Don't underestimate the gear, you will for sure want to bring some stuff you probably haven't thought of yet, tools, grill, pop up rain and bug shelter, a generator or solar module, etc etc.  It adds up quick. 

Compare those two numbers, consider where you will be travelling, and how close you really want to be the limits of the vehicle. I stay about 1000 lbs under my MCGVWR, more than that just starts to feel like a white knuckle experience, especially in the mountains, rainy weather, or on a busy freeway. 

BTW, you should never have both a full fresh and gray tank at the same time. If you're boondocking, empty the gray and black tanks before refilling the fwt. If you have hookups, then you don't need any water in your fwt anyway.

Re shifting weight aft to reduce tongue weight, that is generally not a good idea. You need the tongue weight to always be at least 10% of total trailer weight, more is better. The lower the tongue weight the more a trailer is prone to sway, and rPods do exhibit sway at about 10% tongue weight. I like my tongue weight at 12% or more. Check out this video:

Yes, there are folks towing the mid sized rPods with RAV 4's. There are folks that do or talk themselves into doing all kinds of things that you can read about on the internet. But I think that you will find the consensus opinion on this site is that that is not the way to go. If you do want to tow with the Santa Fe why not get a smaller trailer, like a TAB?