Large capacity fuel (gas) tanks for AT4

[Hrominger]

Searching high and low for a larger gas fuel tank for my AT4 6.2L from 24 gallons, anyone with knowledge of a increased fuel capacity tank for gas engines?

 

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[Paveslave]

Maddening……. The search continues

 

[Paveslave]

Searching high and low for a larger gas fuel tank for my AT4 6.2L from 24 gallons, anyone with knowledge of a increased fuel capacity tank for gas engines?

I am trying to see if the sidekick works for the carbon bed trucks it looks like it’s only for the passenger side. That does not help me.

 

[Teegunn]

As I understand it, from threads on this site from a while back, it isn't legal in the US for aftermarket companies to make a larger tank and one to have it installed in our trucks.

My 23 AT4X with the 6.2 needs a bigger tank than 24 gallons. Should at least be 28 gallons. 32 would be better yet.

To make matters worse, in late Sept of 23, I had a whole bunch of codes pop up on my AT4X. I took it to the dealership, they put their code reader on it, an hour later told me that either my engine was going out, or my transmission. Like, what the hell? I asked them how long they would have to have my truck to fix it, they said at least 3 months, more likely 5 or 6 months, due to parts constraints. My truck is my personal driver and my work truck (I am a contractor). No way I could afford to not have my truck for 3 to 6 months.

So I have been driving the truck anyway. They wiped the codes when I took it in, a month later I took it in to a different dealership and they were able to see all the old codes, but told me it was not a bad transmission or bad engine. Completely conflicting stuff from two different dealerships.

I mention this, because since these codes came up (there were 15 or 16 codes), my truck would get 15 to 16 MPG on hwy driving. I have been working out of state a lot these past 3 years, and where I am working is 1000 miles away from my home state. So lots of hwy miles have been put on my truck over the last year. Getting 10 or 11 mpg instead of 15 to 16 mpg has really cut the range I can go on a tank. I closely track the mileage my truck gets (always have) per tank. Since all these codes popped up, I consistently get about 11 MPG, and I am not driving with a heavy foot. When I do tow my job trailer, I get at least 5 MPG less while towing than I got before these codes.

The truck seems to run normal. The transmission is also pretty normal I think, although if the truck has sat a few days, when I start it up and put it in reverse to pull out of my garage, the transmission "slips" a bit for a few seconds. I don't remember that happening before the codes.

I have actually been looking for a backup work truck, that I can use once I can actually have the dealership do a deep dive into this issue, hopefully figure it out and fix it for me. I have to wonder if the MAF isn't bad, but I know the second dealership that had it had notes on it that said that GM is aware of this issue as I am not the only one with the 6.2 that is having these same problems, but at the time GM had no fix or remedy or even knew what was causing it. The notes specifically said GM felt it was a software issue and NOT to replace the MAF sensor. So basically, GM is saying tough luck, enjoy getting 4 MPG or so less per gallon on your truck.

I have been so busy working out of state and working in general, I simply don't have time to try to find a backup older truck to get me by, and then leave my 23 AT4X at the dealership for what could be many months. To say this sucks is an understatement. I am hoping to have time and a way to be able to take the truck back to the dealership this spring and have this issue fixed once and for all hopefully. Love the truck. Don't love having less than 300 miles range on a tank of gas.

 

[Viking Truck]

There is a company in Idaho that sells supplemental tanks. I know of them from the Jeep world. I dont see any applications on their website that would support a full size truck. I know that this might not help GMC owners but I dont think there are any regulations against adding extra fuel. Lots of farmers, construction guys etc have fuel tanks in the bed of their truck for equipment.

Upgraded Fuel Tanks, Bumpers, and Truck Toppers |Long Range America

Long range fuel tanks for Toyota, Jeep, and Lexus. Shop auxiliary and replacement tanks, Alublack trays and canopies, aftermarket front and rear bumpers, and more.

longrangeamerica.com

 

[Rdnkcaddy]

Probably doesn't help the gassers but a company called Titan makes a 43 gal replacement tank for 1500's. I didn't see anything on their site that would indicate that it is not legal.

https://titanfueltanks.com/

 

[Paveslave]

There is a company in Idaho that sells supplemental tanks. I know of them from the Jeep world. I dont see any applications on their website that would support a full size truck. I know that this might not help GMC owners but I dont think there are any regulations against adding extra fuel. Lots of farmers, construction guys etc have fuel tanks in the bed of their truck for equipment.

Upgraded Fuel Tanks, Bumpers, and Truck Toppers |Long Range America

Long range fuel tanks for Toyota, Jeep, and Lexus. Shop auxiliary and replacement tanks, Alublack trays and canopies, aftermarket front and rear bumpers, and more.

longrangeamerica.com

Yea they do but it’s mostly diesel tanks. No one makes a gas tank as far as I know.

 

[Paveslave]

As I understand it, from threads on this site from a while back, it isn't legal in the US for aftermarket companies to make a larger tank and one to have it installed in our trucks.

My 23 AT4X with the 6.2 needs a bigger tank than 24 gallons. Should at least be 28 gallons. 32 would be better yet.

To make matters worse, in late Sept of 23, I had a whole bunch of codes pop up on my AT4X. I took it to the dealership, they put their code reader on it, an hour later told me that either my engine was going out, or my transmission. Like, what the hell? I asked them how long they would have to have my truck to fix it, they said at least 3 months, more likely 5 or 6 months, due to parts constraints. My truck is my personal driver and my work truck (I am a contractor). No way I could afford to not have my truck for 3 to 6 months.

So I have been driving the truck anyway. They wiped the codes when I took it in, a month later I took it in to a different dealership and they were able to see all the old codes, but told me it was not a bad transmission or bad engine. Completely conflicting stuff from two different dealerships.

I mention this, because since these codes came up (there were 15 or 16 codes), my truck would get 15 to 16 MPG on hwy driving. I have been working out of state a lot these past 3 years, and where I am working is 1000 miles away from my home state. So lots of hwy miles have been put on my truck over the last year. Getting 10 or 11 mpg instead of 15 to 16 mpg has really cut the range I can go on a tank. I closely track the mileage my truck gets (always have) per tank. Since all these codes popped up, I consistently get about 11 MPG, and I am not driving with a heavy foot. When I do tow my job trailer, I get at least 5 MPG less while towing than I got before these codes.

The truck seems to run normal. The transmission is also pretty normal I think, although if the truck has sat a few days, when I start it up and put it in reverse to pull out of my garage, the transmission "slips" a bit for a few seconds. I don't remember that happening before the codes.

I have actually been looking for a backup work truck, that I can use once I can actually have the dealership do a deep dive into this issue, hopefully figure it out and fix it for me. I have to wonder if the MAF isn't bad, but I know the second dealership that had it had notes on it that said that GM is aware of this issue as I am not the only one with the 6.2 that is having these same problems, but at the time GM had no fix or remedy or even knew what was causing it. The notes specifically said GM felt it was a software issue and NOT to replace the MAF sensor. So basically, GM is saying tough luck, enjoy getting 4 MPG or so less per gallon on your truck.

I have been so busy working out of state and working in general, I simply don't have time to try to find a backup older truck to get me by, and then leave my 23 AT4X at the dealership for what could be many months. To say this sucks is an understatement. I am hoping to have time and a way to be able to take the truck back to the dealership this spring and have this issue fixed once and for all hopefully. Love the truck. Don't love having less than 300 miles range on a tank of gas.

Terrible….. they are all the same now sell you a truck and 0 customer service after.

 

[Teegunn]

I know a member or two here mentioned something about regulations that make changing to a larger gas tank tough, or maybe not possible. I am talking a out replacing the stock tank, not adding a bed tank to haul extra fuel.

The thread was probably about 10 months ago or so. I do remember when I went searching for larger tanks online, that I could not find a single place that offered larger tanks. And then a member or two here said that's because DOT (or similar) doesn't allow a non-factory larger tank to be installed. Whether that is actually the case, I don't know for sure.

 

[Teegunn]

Terrible….. they are all the same now sell you a truck and 0 customer service after.

Agree. I did get my 2020 AT4 right after the start of Covid, and the factory incentive deals and dealership discounts were large. I also have a friends and family code discount I used. Got the 2020 AT4, which MSRP'd at almost 60K, for 50K. Then they gave me 45K when I traded it for my AT4X almost 3 years later.

But I wouldn't have even traded my 2020 AT4 3.0 diesel if it hadn't come up with the service emissions codes and progressive limp mode. The fact that they could never figure out the problem and had the truck a month was ridiculous. Now with my 23 AT4X, since the 15 code issue in late Sept happening, and two dealerships having no idea why my gas mileage has taken a huge hit or why the codes came up, is also more than frustrating.

Also, my 23 AT4X had the camera on the rearview mirror go bad in June. I finally got around to taking it to the dealer for them to fix it, they ordered the new camera on Sept 11, 2023. 5 months later to the day, they still have not received the replacement camera. I paid a pretty penny for the truck, but GM can't even get something like a camera part in now 5 months. I love the rear view mirror camera, miss having it. But it's not as bad as having 80 miles of range per tank cut off of your MPG. Just the extra fuel costs alone add up.

Get your ish together, GM.

 

[Viking Truck]

Yea they do but it’s mostly diesel tanks. No one makes a gas tank as far as I know.

There are many diesel owners on here.