Trailhunter auxiliary gas tank

[Cordoc]

I recently completed a trip from East TN to WA and points in between. The trip covered 7675 miles over varied terrain and driving conditions including 200+ miles of off road driving some in 4WH and 4WL. The trip began with roughly 2300 miles on my Trailhunter and finished just shy of 10k. I ran the truck across a scale and it was 6660 lbs loaded about 175 lbs below the GVWR. Here is a synopsis with actual data below. Note the truck includes the OEM roof rack and an Alu-cab contour canopy top with roof mounted MaxTrax, otherwise wheels and suspension are stock.

Average: 17.25 mpg
Plains SD, KS, etc. 75-85 mph Speed limit 14-15 mpg
White Rim Trail 2WD, 4WD H & L 12 mpg
Reduced speed and lack of wind 19-20 mpg

In some cases where gas mileage was high it wasn't clear why based on driving conditions. The same is true for some lower mpg results. It's possible the exact gas formula plays a role. Most but not all driving was in ECO mode, but since 4WD kicks it out of this mode I didn't always notice it was off. As others have noted, it is not clear that ECO has a significant effect on highway driving which covered much of this trip.

While the average MPG wasn't as bad as I anticipated based on others comments. The most frustrating thing as that I had to stop for gas at 200-250 miles where I generally drive 300 before stopping. There is one result below at 282 miles in ID where I ran 10-20 miles below what the truck says was empty. According to gallons added there should have been 1.5 gallons or more left so there is a little wiggle room in what "empty" is per the gauge. Nonetheless, it is concerning when you are in remote areas where gas is limited and far between. Needless to say, I would love to have a tank that adds 4-6 gallons to increase the real world range of this truck.

Date	State	Octane	Odometer	Miles	Gallons	MPG
8/30/2025	TN/KY	87	2547	229.3	14.486	15.83
8/30/2025	KY	87	2631	84	4.994	16.82
8/30/2025	MO	87	2896	264.9	15.006	17.65
8/31/2025	IA	87	3138	242.2	14.151	17.12
8/31/2025	SD	87	3397	258.4	14.45	17.88
8/31/2025	SD	87	3633	235.7	15.987	14.74
9/1/2025	SD	87	3830	197.3	12.758	15.46
9/1/2025	ND	87	4077	246.6	13.587	18.15
9/2/2025	ND	87	4252	---	6.202	NF
9/3/2025	ND	87	4414	337.6	12.412	18.14
9/3/2025	ND/MT	87	4597	182.3	11.964	15.24
9/3/2025	MT	87	4851	254.1	14.54	17.48
9/4/2025	MT	87	4958	106.7	6.125	17.42
9/4/2025	MT/ID	87	5154	196.3	9.765	20.10
9/4/2025	ID/WA	87	5290	136	6.704	20.29
9/4/2025	WA	87	5484	194.7	10.308	18.89
9/5/2025	WA	87	5734	249.8	12.604	19.82
9/6/2025	WA	87	5931	196.6	9.928	19.80
9/6/2025	OR/WA	87	6171	240	13.415	17.89
9/6/2025	WA	87	6327	155.5	10.205	15.24
9/7/2025	ID	87	6609	282.1	16.391	17.21
9/8/2025	MT/ID	87	6783	174	11.141	15.62
9/8/2025	ID	87	6923	140	7.605	18.41
9/9/2025	ID/UT	87	7165	242.4	13.579	17.85
9/9/2025	UT	88 No EtOH	7342	177.4	9.264	19.15
9/10/2025	UT	87	7582	239.4	12.653	18.92
9/10/2025	UT	88 No EtOH	7725	142.7	8.811	16.20
9/11/2025	UT	88	7896	171.1	10.268	16.66
9/12/2025	UT	87	8072	176.5	10.803	16.34
9/13/2025	UT	87	8150	77.6	4.01	19.35
9/14/2025	UT/CO	87	8399	248.7	18.755	13.26
9/14/2025	CO	87	8597	198.3	11.434	17.34
9/14/2025	KS	87	8866	269.3	14.817	18.18
9/15/2025	KS	87	9066	199.3	13.368	14.91
9/15/2025	MO	87	9301	235.5	13.435	17.53
9/15/2025	MO	87	9530	229.1	12.523	18.29
9/16/2025	KY/TN	87	9764	233.8	13.922	16.79
9/16/2025	TN	87	9995	230.3	12.474	18.46

Thanks for this, great record keeping.
This is more proof of the problem . A marriage of a hungry power train and a small tank.
I honestly do not think that a replacement tank will ever arrive and that we will have to use portable tanks forever.
Otherwise it is a great truck.

Sponsored

 

[mtbocoee]

Prices weren't bad in the Midwest, but not that low. Worst was $4.70 in WA just east of the North Cascades. The entire trip cost $1454 in gas.

 

[TacoFreak]

I honestly do not think that a replacement tank will ever arrive and that we will have to use portable tanks forever.

Yeah, there just isn't a lot of space under there for a larger tank, and portable might end up being our best (only) option.

 

[Pappy]

On the way out from Florida on my trip in June, I bought gas at a Loves' outside Oklahoma City on I-40. Notice the price, I could not believe it!

Suggestion. Get the Loves app. You can save 10 cents/gallon at the pump.

Also get the Pilot/Flying J app. I don't remember if they discount at the pump or not. I just did a 13K mile trip to Canada and Alaska. Loves truck stops were my friend and I would always seek them out.

Third option, though not as generous, is Maverik. They give 3 cents off/gallon.

 

[Pappy]

Yeah, there just isn't a lot of space under there for a larger tank, and portable might end up being our best (only) option.

I think there is a spare tire tank in our future. I certainly hope so. I know of two companies working on it.

 

[TFOUTS]

Suggestion. Get the Loves app. You can save 10 cents/gallon at the pump.

Also get the Pilot/Flying J app. I don't remember if they discount at the pump or not. I just did a 13K mile trip to Canada and Alaska. Loves truck stops were my friend and I would always seek them out.

Third option, though not as generous, is Maverik. They give 3 cents off/gallon.

I have both Loves, Pilot, Circle K, and Maverick. Good deals

 

[mtbocoee]

I had to satisfy my curiosity because I was thinking that the Trailhunter mpg was not significantly different from my 2000 Tundra extended cab with a 4.7l liter V8 that I had taken on previous trips. They only significant mod to this truck is the addition of a Leer fiberglass cap. Payload would be similar if not more because in past years I took a mountain bike and all associated gear and clothing.

Somewhat surprisingly the results are similar. Granted the two trips are not identical, but they do cover quite a bit of common ground though there would have been limited driving in 4WD on last years trip. The Tundra averaged 17.42 mpg over 4158 miles. The data are below:

Date	State	Octane	Odometer	Miles	Gallons	MPG
9/1/2025	KY	87	311948	300.0	17.086	17.56
9/1/2025	MO	87	312260	311.2	17.902	17.38
9/2/2025	KS	87	312505	245.5	14.484	16.95
9/3/2025	KS	87	312625	119.9	7.890	15.20
9/4/2025	KS	87	312807	182.0	10.250	17.76
9/4/2025	CO	85	313026	218.4	13.636	16.02
9/5/2025	CO	85	313295	269.3	13.490	19.96
9/9/2025	UT	85	313611	316.1	19.431	16.27
9/10/2025	UT	85	313791	179.3	10.749	16.68
9/11/2025	AZ	87	314044	---	10.109	NF
9/12/2025	NM	87	314211	420.8	13.367	17.92
9/12/2025	TX	86	314576	364.9	18.285	19.96
9/13/2025	OK	87	314891	314.7	18.194	17.30
9/13/2025	AR	87	315090	199.9	11.642	17.17
9/14/2025	AR	87	315360	269.5	15.520	17.36
9/14/2025	TN	87	315498	138.1	7.780	17.75
9/28/2025	TN	87	315807	308.4	18.888	16.33

It would appear that Toyota managed an engineering marvel in creating a 4 cylinder that equals the gas mileage of their 25 year old V8. To be far, I think the GVWR of these two is similar as the Tacoma has grown to a full size equivalent if compared to 2000 full size pickups.

 

[Pappy]

I think there is a spare tire tank in our future. I certainly hope so. I know of two companies working on it.

The folks at Helivue Design are taking pre-orders on an 18 gallon auxiliary gas tank for the Gen4 Tacoma. Pre-order price is $2000, which is $300 less than list price , so you can save a few bucks ordering now.

So, quit whining about our fuel range and solve the problem.

https://helivuedesign.com/products/2024-current-toyota-tacoma-auxiliary-fuel-tank-system-18-gallon

 

[TrailAdventurer]

quit whining about our fuel range and solve the problem.

Good to see there’s finally an option—but for those of us who actually need meaningful range, this still doesn’t solve the underlying OEM gap.

Most people aren’t installing this themselves. By the time you factor in install—often ~$1K—a ~$3,300 total price tag, it’s a pretty expensive workaround.

If the factory tank and range were even marginally better, the need for a long-range solution like this would drop off for the majority.

 

[Pappy]

Most people aren’t installing this themselves. By the time you factor in install—often ~$1K—a ~$3,300 total price tag, it’s a pretty expensive workaround.

We shall see. I asked them about installation cost. It also sounds like installation is possible if you have any skills.

 

[TrailAdventurer]

We shall see. I asked them about installation cost. It also sounds like installation is possible if you have any skills.

Forgot to include, my install estimate, based on putting a LR tank into a Wrangler.

 

[rchrds]

Also take into account, that much weight over the rear axle is going to require suspension improvements. Those of us that have already buttressed the rear springs with dobbesons or air springs are ok, but otherwise, this is gonna sag the bed significantly when full.

 

[AZTaco]

I wonder why they went with an 18gal aux tank vs a 30+gal replacement tank? The "programmable Fuel transfer switch/fuel level gauge, quality fuel pump, and stainless steel fuel level sender" has to add cost and complexity over one big tank that (possibly) uses the original pump and fuel level sensor. Still like to see if the Tundra 32gal tank would fit.

 

[Great White North]

After about 4K miles, most of it on HWY driving, I find it quite hard to go more than 14mpg, normally it is below that.
Out West there are long, 75+ stretches of no gas availability and, when I start doing Overlanding I am sure the gas mileage will be around 12.
Does anyone have any ideas on how to retrofit an auxiliary tank, 5 to 10 gallons on these trucks?
Thanks a lot

I purchased my TRD-Off Road Premium Tacoma in 2024 and I haven't had any major issues with the 4th generation Tacoma other than the size of the gas tank.

2024: Fourth Generation Tacomas

The fourth-generation Tacoma, which was newly released in 2024, introduces a smaller fuel tank size of 18.2 gallons. This is the biggest drop since the first-generation Tacoma.

However, with the Tacoma’s new 4-cylinder i-Force and i-Force MAX engines, the improved fuel efficiency of 20-23 combined brings the estimated range on par with the previous generation. Estimated ranges start at 364 and can be as high as 419.

-Source - https://tacomaexplorer.com/toyota-tacoma-gas-tank-size/

Just to clarify, it is not so much the size of the gas tank as it is finding a cost effective solution for remote long haul trips. I fish and hunt in remote areas of northern Alberta where gas stations can be 200-300 km apart which creates some challenges depending on the road and weather conditions at the time.

I was hoping the Titan Side Kick II was going to be a solution for the 4th gen Tacoma (Titan Fuel Tanks 15 gallon- $349.00 US plus shipping). I just received my Titan Side Kick II order from Titan Fuel Tanks and I quickly realized I would have to give up access to the rear power and air compressor panels, especially with a short box vs a long box bed.
Driver Side Perspective Without Titan Side Kick Tank
View attachment 5629
Driver Side Perspective With Titan Side Kick Tank
View attachment 5630
Passenger Side Perspective Without Titan Side Kick Tank
View attachment 5631
Passenger Side Perspective With Titan Side Kick Tank
View attachment 5632

I reached out to Titan Fuel Tanks customer support to confirm that I have received the correct model for the Tacoma and the model I received was suppose to be a solution. After I submitted pictures of my box bed to demonstrate the installation issues, the support team recognized this would not be a solution for 4th gen Tacoma with a short box. I can not confirm if the Titan Side Kick II would fit a 4th gen Tacoma with a 6' box bed or not.

The Ford Ranger has the same gas tank challenges for long haul trips and the Titan Sidekick II is an effective solution since the Ranger doesn't have similar power and air compressor panels in the box bed.

I have included a link for the Titan tanks installation tutorials to provide a visual of what involved in installing such a solution in a mid-sized truck.
Titan Fuel Tank Side Kick II

Ford Ranger Installation example

I have managed to find a couple Aussie and North American solutions (Helivue 18 gallon secondary tank solution), but there are concerns about the installation location and clearance issues for those who travel terrain with large rocks.
Helivue 4th Generation Tacoma Gas Tank Supplement

Brown Davies 150 liter 2026 Tacoma Solution

Normally this would be the first company I would source such a product, but they are still taking feedback requests for determining the market need for the 4th generation Tacoma. We need more people reaching out to get a reliable solution in place as soon as possible.
Long Range America 33 Gallon Solution (2005-2023)

Please complete the information request form which will hopefully demonstrate a business case for creating a solution for the 4th gen Tacoma in North America.

I would appreciate any information about long haul solutions if someone has come across one.

 

[Cordoc]

I ordered the 18-gallon aluminum tank that this thread was about.
I have not yet received it so I can not comment on its good and bad points, BUT, although it goes where the spare now is, creating the problem of where to put the tire, it is the most logical and cost-effective solution for me.I will be happy to make a report after the thing is installed and I have put some miles on the truck with it..

Sponsored