I'm trying to decide which cover to get for my F450. My main requirement is that it is nearly flush with the bed rails as I'm pushing clearance limits with the taller truck and my fifth-wheel camper anyway.

The main contenders are a roll top (Pace Edwards, Truck Cover USA, Roll-n-lock) or a BakFlip F1. I'm surprised how much smaller an aux tank will be with the roll cover. The main reason I'd like an aux tank is for ballast weight to settle the F450 ride down, so the closer to 100 gallons (800# for fuel+tank), the better. The extra range is a nice bonus. Here are some thoughts:

I can fit a much larger aux tank without the roll canister:
Attatank 18" wide:
- w/ roll cover notch = 45 gallons
- w/o roll cover notch = 80 gallons (roll cover loss = 35 gallons)
Attatank 25" wide:
- w/ roll cover notch = 72 gallons
- w/o roll cover notch = 110 gallons (roll cover loss = 38 gallons)

Not, that assumes that I can fit the 18" tall tank with the 20.5" high sending unit / fill neck under the Bakflip. I may need a custom 17" tall tank, which case the size would be 75/104 instead of 80/110. Still would lose 30+ tank volume for the same loss of bed space if I got a roll top cover.

I could also consider the ultimate combo: Truck Cover USA Work Cover JR (w/ small tool box on top) and the 45 or 72 gallon attatank. Decisions... decisions...

What do you think?

 

I installed the RetraxPro MX on my 450. I plan to install an Auxilary tank from Fuelbox seen here Auxiliary LT70T | The Fuelbox

I think it will fit nicely. I emailed them to confirm measurement "A" included the cap and sending unit - which it does.

 

I have the Truckcovers roller with the regular toolbox.
There is just enough room under there to fit a RDS 45 gallon tank.
The 45 gallon tank could be 8" wider though.

Since I plan on putting this cover on the next truck and possibly not doing a Titan tank, I am considering having a tank made this time. Local marine fuel tank shop will make it to my specs.

 

I have had ATTA tanks before and in fact had the AT45L-RT in my old F350. When I got the F450 I knew I wanted a little more tank but didn't want to go overboard.
In talking the Nick Humphrey at ATTA Tank they simply expanded the 45 gallon to a 55 gallon and it worked out great. Cost $100 more.
My rolltop is a RETRAX.


Bigdon68

 

Bigdon, can you give me more details on your 5th wheel hitch? I don't want to hijack this thread, so even a PM would be cool.

 

Bigdon,

Wanted to let you know that your set-up has been a working model for me. My F450 gets delivered this week, my TS3 hitch should be delivered on Wed, the Retrax Pro is in the shop waiting install and our new DRV 40KSSB4 (with 2" risers) shoud be in by mid-April. Thanks for your help and paving the way!

 

I too have the RetraxPro, and this aux tank looks awesome! Thanks for the tip!