I did a repair on a friends 5'ver a number of years back. He had a 10 gallon tank that died in a CG we were both staying in. He bought a new unit at the local RV place and I swapped it out for him.
The tank itself was ok, so I kept it, thinking I would repair it an swap mine out, going from 6 to 10. I wish it was that easy.
As mentioned, physical size difference.
For obvious reasons, the 10 is bigger. It requires a bigger opening to fit in. This requires surgery on the wall of the RV to provide solid framing all around to screw the unit in.
On mine, I didn't have enough extra width and height to make it an easy conversion. I would have had to carve up a partition, do cosmetic repairs and more, so I scrapoed the idea.
However, if you have enough extra width and height inside, and you're willing to enlarge the opening of the outside wall, yes it is doable.
2007 GMC 3500 dually ext. cab 4X4 LBZ Dmax/Allison - 2007 Pacific Coachworks Tango 306RLSS
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