Boldt fuel tank upgrade complication

[raytaylr]

I consider the 24 gallon tank, 384 mi range at 16mpg, size too small for my comfort on what I consider our "long range" rig. Looked for and found a 47 gallon tank, 752mi range, that will bolt in in place of the OEM tank. S&B Filters offers the tank for around $1500 uninstalled.

I was ready to order but a question came up regarding the fuel gauge recalibration. Turns out the OEM setup calculates fuel level/range not using the float in the tank and would not read the 47 gal tank correctly. I was told that a software/firmware upgrade, "J51" was necessary to read the fuel level correctly using the float. Called 3 MBZ dealers in the area and can't get anyone to help me get this done. Most often response is "we don't do modifications to our vans"

I found an independent who "ordered" the J51 for my van by VIN, billed me $180 and said I'd need to find a dealer to do the upgrade.

Has anyone done this upgrade? How did you get the fuel gauge recalibrated?

[creativepart]

Have you checked that the new tank will actually fit into the RV? You sound like you are making assumptions about a stock Sprinter, not one massively modified for use as a motorhome. Seems like a risky assumption. It may fit, but I’ll wager no one else has made this modification to their very expensive RV.

[raytaylr]

Yes, I very carefully checked for fit on my VERY expensive RV and it does. I'm not new to this and have done MAJOR upgrades on my RV to include a hydraulic jack leveling system, suspension upgrades and more.

What is the "Very Expensive RV" comment about? No modifications suggested unless its a cheapy? You drive a 37' monster, how big is your tank? Thanks for your concern for my wallet.

[creativepart]

Sorry, no offense meant. The Boldt is a beautiful RV and the most expensive Class B in Winnebago’s extensive lineup. My first thought when you asked your initial question was, “Will that even fit?” So, yes, I was concerned for your wallet as you made no mention of checking anything but the software.

Again, no offense meant and I apologize that my post seemed out of line to you.

PS. My RV no doubt cost less than yours. It has an 80 gallon tank (all gas class A’s are so equipped). And since we drive no more than 200 to 300 miles a day our tank is plenty. If anyone makes a larger one, I’ve never heard of it.

[raytaylr]

No offense taken, just sounded a bit off base. These are VERY expensive RV's and the build, unfortunately, doesn't consistently match up to the high price on the truck or house side. Luckily I got an outrageous deal on my rig when bought new and I love doing the DIY upgrades, so yea I can be a bit sensitive.

This refusal to help with a simple alteration that will enhance my experience, along with several other experiences with Mercedes makes me feel they are simply arrogant. The trash sound system with a blaring center speaker, auto high beam system that won't work under 16mph where you need it most, a fuel system that won't allow biodiesel and lastly an operator interface that focuses on unimportant info and doesn't allow for the operator to set up what they feel they need to see rather than buried and resetting to their default certainly takes the shine off this VERY expensive RV. I wish the Transit would have been ready when we bought.

Wow, got that off my chest!

[Eagle5]

Maybe these guys could help you out with the calibration?
https://agileoffroad.com/
Below is a pretty cool video about the same modification, but with a Revel.
Eagle5

Double your Winnebago Revel's fuel range!