Fresh Water Tank Question

Ralph Cramden wrote:
Fill it up, drop the under liner, how much is the tank sagging down? Possibly about 30 gallons worth of sag in the middle? Sounds like a lot however. Better than laying on the highway I suppose.

A sagging tank and an incorrectly placed pump draw were the 2 issues I had with my Coachmen Freedom Express, a Forest River company. The fix was easy - moved the pump draw down to the drain port on the bottom of the tank and installed a steel beams to better support the tank & prevent it from sagging when full. Mine's a 2014 model but AFAIK the new 2018s still lack the proper support. Pics start here.

Thanks for all of the replies!!

I'll wait to see what Keystone has to say when/if they get back to my e-mail after the holiday weekend before I tear into it and try to tee into the drain fitting. Definitely a great idea, though!!

Ralph Cramden wrote:
Ahhhhhhh Forest River water tanks.

Fill it up, drop the under liner, how much is the tank sagging down? Possibly about 30 gallons worth of sag in the middle? Sounds like a lot however. Better than laying on the highway I suppose.

Seriously, they have problems with their tank supports and more than a few are known to have sagged a good 4 or 5 inches, and some pop right out on the road. Some factory reps have even made statements in open forum they are not designed to be moved with full tanks which is how they interpret that little yellow sticker that says so many gallons weigh X lbs and needs to be deducted from cargo capacity.......anything works when it comes to skating around a deficiency I guess.


39 gallon tank on our 17 Rockwood, tech had it filled for the PDI. I told him to leave the 3/4 remaining in so I could see how it towed on the 70 mile drive home with water aboard. It barely made it. I was underneath with welder and steel the 2nd day of ownership. I am fairly certain Coachmen uses the same exact supports, which is a standard POS Lippert item.....too light for the load.

Ooops.....I stand corrected. Noticed the Coachmen in the OP's sig. Carbon Creek = Thor/Keystone. Still, unless that tank is sitting on a solid floor, I would investigate it's supports.

Ahhhhhhh Forest River water tanks.

Fill it up, drop the under liner, how much is the tank sagging down? Possibly about 30 gallons worth of sag in the middle? Sounds like a lot however. Better than laying on the highway I suppose.

Seriously, they have problems with their tank supports and more than a few are known to have sagged a good 4 or 5 inches, and some pop right out on the road. Some factory reps have even made statements in open forum they are not designed to be moved with full tanks which is how they interpret that little yellow sticker that says so many gallons weigh X lbs and needs to be deducted from cargo capacity.......anything works when it comes to skating around a deficiency I guess.


39 gallon tank on our 17 Rockwood, tech had it filled for the PDI. I told him to leave the 3/4 remaining in so I could see how it towed on the 70 mile drive home with water aboard. It barely made it. I was underneath with welder and steel the 2nd day of ownership. I am fairly certain Coachmen uses the same exact supports, which is a standard POS Lippert item.....too light for the load.

"As designed" is the all-purpose excuse for low quality.

As designed? Assuming a 90 gallon tank they could have designed it with a 60 gallon tank and the pickup in the right location.

Old-Biscuit wrote:
The technicians "as designed" statement is one used 'as designed' to make you go away...

A little off topic but I took our car in under warranty. It was blowing water vapor from the vents in hot humid weather with the A/C on. Obviously evaporator drain was plugged. They checked it out and service tech said "Nothing wrong, all vehicles do that." I said "Really, been driving air conditioned cars since the 1970's and never had one do that." Worst part, GM had already issued a Tech Bulletin stating the drain tube could have been pinched during assembly.

I've never seen a FW tank with a pickup tube. They all have bulkhead fittings that I've seen. Sounds to me like changing the suction side of the pump to the drain fitting (like others have done) is the answer.

It may "be as built" but definitely not "as designed".

My last trailer had the fitting on the side and left about 1.5 gallons when sucking air.

My current trailer has the fitting on the bottom so it gets every drop of the 100 gallon capacity.

TurnThePage wrote:
I had a similar issue. I ended up Teeing off the the freshwater tank drain and pump from there. I get every drop that way.

This is what I did also. Very simple fix.

Safe travels.

I would ask the tech for something in writing to show it's 'as designed.'