new to the TT world

To the OP...as you can see here there are about as many opinions here as there are different rigs. My suggestion is try both and do whichever is best for you and your camping style. There is no right or wrong way. Once you camp a few times you will develop your own system and it will become routine to you personally. Don't sweat the small stuff just get out there and enjoy it! Personally I have never put a drop of water in the freshwater tank.

Guys with half ton trucks and 18'TTs get essentially the same mileage as rigs twice as large. Because once you get them up to speed, only one thing really matters: Wind resistance. Aerodynamics is much more significant than a few hundred pounds of water.

Notice nobody here is really making a big argument for mpg difference being a major consideration. As most have mentioned, they didn't notice the difference. All so called mpg experts, everywhere, says weight makes a difference. They just won't say how much ( or how little ;).
RVs with smaller CCC, then the extra water can make a noticeable difference. WHEN I start traveling anticipating dry camping, I will haul 1/4-1/3 tank for bathroom use. I will have to cut back more on the stuff we have previously packed in the TT.
I have previously used the cheaper in line water filters for CG use and now have a better quality one.
I, too, haul filtered water in jugs for drinking & cooking. I have found out how much I need per day average and cut back on those jugs, again to save CCC weight. When traveling for extended time, I will use my Berkey style drip filter for clean, fresh water.
My wife treated stocking the TT like a cabin on the lake. After my CAT scale weighing, we cut back significantly and keep aware of not taking a lot of extra nice to have, just in case, but seldom or never used stuff. Last camping trip was our most easy going, laid back, and we packed about half as much as before. Last year was our first year with a TT.

profdant139 wrote:
True, the MPG will not vary much, empty or full. But the more "deadweight" you carry, the more the wear and tear on your running gear -- the trailer's and the tow vehicle's suspensions and tires. So that is something to consider. Not a huge make or break issue, but not irrelevant, either.

I often wondered what that extra weight would do to MPG. When we purchased new, they left the freshwater tank about 2/3 full. We pulled home and was even able to run on cruise control for several mile stretch on the flats with our 1/2 ton.

Since then, we've been pulling with empty tanks and have yet to experience a time when the truck felt like it could effectively pull while on cruise. Last trip we filled about half full and it seemed to pull easier and track better. Not sure if the water is putting weight on the trailer springs to allow it to track easier or what. Lowering center of gravity? Dunno. Our trailer has approx 2200lb cargo capacity so maybe the beefy springs are smoothing out with the weight.

Never noticed a difference in MPG with water on board (grey/fresh/black). Lucky, I guess.

True, the MPG will not vary much, empty or full. But the more "deadweight" you carry, the more the wear and tear on your running gear -- the trailer's and the tow vehicle's suspensions and tires. So that is something to consider. Not a huge make or break issue, but not irrelevant, either.

i was waiting until we got to the camp ground to fill my first few trips. we got set up one friday night, camper leveled, plugged in, unhitched and as i was putting the awning out the wife says "did you fill the water tank?" had to break down and go fill up.

Now i realize that the extra small fraction of an MPG isn't worth feeling like a dumb*ss lol. filling the water tank is now part of my procedure the night before we leave.

I always travel with my fresh water tank full. I am just a weekend camper. I fill it up the day before, when I get to the campground I am ready to go and do stuff, I don't want to waste the time to fill the tank.

The water at the campground might not be that good.

And, some of the campgrounds I go to are a First Come, First Serve basis so I want to grab a spot right away.

Full or nearly full here. I have not noticed much of MPG difference.

Depending upon your configuration, a full tank may make the TT more stable in winds. A lot of weight low and directly above the axles. My rig has very little difference in hitch weight full or empty, but pulls a whole lot more stable. Also, you never know when you must make an unplanned overnight in someplace dry.

Just because a CG water supply meets health and safety standards does not mean it tastes good. Plenty of times I found the water undrinkable because of minerals and smell.

K_and_I wrote:

ependydad wrote:
Y'all

You've been in the South too long. Time to head back North.:B

:D

Someone once told me that Florida technically isn’t “the South” because most everyone are transplants.

I tried explaining that to a Floridian the other day- she was offended. I probably should have done it *after* we got our food!

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