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50 Gallon Fuel Tank

Didn't even think about that. Thanks for the input, I feel a lot more confident about the tank capacity now.
 
What's your total tank volume?

Also, did you recal the low fuel warning % trigger?
So I know this is old at this point but didn’t notice or missed someone responding to you about this. About to install the Titan 50gal in my 21 3500 mega, would like to know what I need to do for the warning %? Thanks
 
So I know this is old at this point but didn’t notice or missed someone responding to you about this. About to install the Titan 50gal in my 21 3500 mega, would like to know what I need to do for the warning %? Thanks

Here's what I see in my BCM file related to "fuel"

VehConfig 3:
___________________
...
Fuel Capacity (36-290L): 189.000 Liters

Cluster:
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Fuel Tank 1 Calibration, Empty: 2%
Fuel Tank 1 Calibration, LFW: 8%
Cluster:
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...
Fuel Tank 2 Calibration, Empty: 2%
Fuel Tank 2 Calibration, LFW: 8%
 
You shouldn't have to adjust anything but the VehConfig 3 - Fuel Capacity to 189.000 liters. All the rest works fine with an OEM fuel sending unit (or a replacement one from Auto-Zone, as I broke the plastic ring on mine).
 
Did anyone ever figure out the part number for the factory 50 gallon tank? I'm not paying for a titan tank and having the tank hang lower is not an option.
 
Ok tank is in and filled. Nice seeing over 800mi on the dash. I wouldn’t recommend doing in the driveway while the snow is melting…
Another question…how do I get the bypass cable disconnected?? I’ve got the obd2 disconnected but the other two cables will not come out. What am I missing?? And thank f I left those connected but tied up the bypass obd2 could the dealer still tell it’s there with a scanner?? I’ve got an inspection tomorrow of course. Thanks!
 
Ok tank is in and filled. Nice seeing over 800mi on the dash. I wouldn’t recommend doing in the driveway while the snow is melting…
Another question…how do I get the bypass cable disconnected?? I’ve got the obd2 disconnected but the other two cables will not come out. What am I missing?? And thank f I left those connected but tied up the bypass obd2 could the dealer still tell it’s there with a scanner?? I’ve got an inspection tomorrow of course. Thanks!
Hmm, I left my bypass connected, it's just not plugged into the OBD port, and I have it tucked/tied up out of the way.
 
There are small tabs inside of the top of each connector. Need a small screwdriver or something similar to insert and push down on them to release.
 
Hmm…so I’ve driven/towed about 330 miles…today. My range gauge is saying I still have about 375 miles till empty. My tank gauge is still showing 3/4 of a tank. I’m averaging about 10.5 mpg. I feel like something isn’t right.
 
Hmm…so I’ve driven/towed about 330 miles…today. My range gauge is saying I still have about 375 miles till empty. My tank gauge is still showing 3/4 of a tank. I’m averaging about 10.5 mpg. I feel like something isn’t right.
I have the S&B 52 gallon tank. This is my experience after about 10-15 fills:
The OEM fuel gauge calibration is not linear with this tank. The top 10 gallons of the tank are above the float so until those gallons are depleted, the tank continues to read full and the distance to empty is incorrect. After that, the gauge and DTE will decrease as the float moves down. From this point on, the gauge and DTE are somewhat accurate until about 1/3 of a tank and then they both go down very quickly. When the fuel gauge reads about empty and the DTE is 25 miles, I have about 8 gallons left in the tank.
I think you need to run through a few tanks to get a feel on the gauge and DTE.
 
I have the S&B 52 gallon tank. This is my experience after about 10-15 fills:
The OEM fuel gauge calibration is not linear with this tank. The top 10 gallons of the tank are above the float so until those gallons are depleted, the tank continues to read full and the distance to empty is incorrect. After that, the gauge and DTE will decrease as the float moves down. From this point on, the gauge and DTE are somewhat accurate until about 1/3 of a tank and then they both go down very quickly. When the fuel gauge reads about empty and the DTE is 25 miles, I have about 8 gallons left in the tank.
I think you need to run through a few tanks to get a feel on the gauge and DTE.
Yea I hear you. This is the first trip since installing and I’ve only had it in about a week… I filled up this morning and put 34 gallons in it. So assuming 50 gallons and 16ish remaining it doesn’t look good for the gauge. At least I have an idea for mileage. I’ll continue to play around with it, I don’t need it 100% accurate but need something a little better than 3/4 with only 16 gallons left.
 
Ok…So changing from 189.000 liters to 194.000 liters seemed to resolve the problem. I’m not sure why though. At 189 it wanted to continuously show a quarter tank or better. I tried several numbers and finally 194 that I saw was the max. Once I entered that the gauge dropped to just over a quarter tank. I had about 360 miles towing at almost 11mpg. The math seemed right. I filled up and put 36 gallons in and the DTE started to climb as I drove without the trailer. So for some reason with my 21, 194 seems to do the trick. I’ll see how it actually works when we leave for home next week. Thanks for the responses.
 
Does anyone know how much ground clearance you lose by switching to say the S&B 52 gal tank compared to the 31 gal stock tank?
 
I think it says right on their website.
Wow, you're correct...thanks. It's amazing what I can learn by reading, haha. I hadn't even looked at their website, only talked to the guys at the off-road shop and they didn't know but they said it hangs down quite a bit. According to the S&B website though it's only 2.4" lower than the OE tank.

The S&B website does say though that "The fuel gauge will continue to work however the distance to empty will not be accurate. There is not a way to update the fuel tank size for the distance to empty to be accurate." That's seems odd considering I have seen a bunch of posts in this thread explaining how to easily adjust the DTE to your new tank size...
 
Wow, you're correct...thanks. It's amazing what I can learn by reading, haha. I hadn't even looked at their website, only talked to the guys at the off-road shop and they didn't know but they said it hangs down quite a bit. According to the S&B website though it's only 2.4" lower than the OE tank.

The S&B website does say though that "The fuel gauge will continue to work however the distance to empty will not be accurate. There is not a way to update the fuel tank size for the distance to empty to be accurate." That's seems odd considering I have seen a bunch of posts in this thread explaining how to easily adjust the DTE to your new tank size...
You can adjust the tank size, but only up to a certain amount. So you can go up to I assume the biggest factory tank of 50 gallons but not beyond that.
 
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