Hey guys, 1998 Wrangler, looking for advice on mounting a 5 gallon tank. I’m seeing people mount a 2.5gal under the drivers side next to the driveshaft and frame rail. Any advice, or writeups you could share? Is a 5 gallon too big? I assume it’s a bad idea to place the 5 gallon tank in the trunk/bed. Thanks all
Welcome to the forum. Browse the internet for “skinny air tanks”. They have a diameter similar to the 2.5 gallon tank but are much longer.
My first install had a 2.5 gal tank strapped underneath the car and I hated it. Every time you take the car off-road you’ll be worried about hitting hit. Consider also that you’ll have a drain tap and possibly other fittings poking out underneath, which makes clearance & gunk/grime buildup even more of an issue.
5 gal is a great size - what’s the problem with putting it into the trunk/bed?
Well, I have my first child due in 5 months. At times, the baby may ride in the jeep, and I don’t feel safe having the tank behind the baby. So you weren’t happy with the 2.5gal? I’m starting to think this isn’t a good idea now.
Quite the contrary - I loved it. Still have it. I started with it, then moved it to the wife’s car when I upgraded. I just didn’t like it hanging underneath the car. Get quality fittings, drain your tank regularly and have a safety valve fitted, - then you won’t need to worry about having the baby riding the tank 
You can always drain the pressure you know … for when the kids are on-board.
Train horns are always a good idea … don’t let people put doubt in your mind 
I didn’t know that was an option! So, if kiddo was to go in the jeep with us instead of the other car, I can drain it and it’s no longer a pressure bomb waiting to go boom? Please tell me that’s really an option, if so I’m mounting that poop right in the back of the jeep! Assuming it’s a simple thing to do!
Not only is it an option - I’ll give you two for the price of one:
- Open the tank drain; or
- Honk your horns (on 2 gallons you’ll have less than 5 seconds to wait)
Just make sure you wire in a cutout switch to stop your compressor from refilling the tank of course.
If you put a 5 gal into the back, you could also consider putting in an electronic tank drain. Just drill small hole in the back somewhere and run a pipe down from your lowest tank port to underneath the car and onto a secondary solenoid. When you need to purge the tank all you have to do it hold a button.
So let me ask, maybe I’m going better this route.
http://www.trainhornkits.net/air-lift-4-gallon-pancake-air-tank
I can mount this under the cab and keep my trunk storage.
The horns I have are-
https://www.hornblasters.com/products/details.php?i=shocker-540-train-horn-kit
Wondering if that pancake tank will work.
Any tank will work. You just have to measure the clearance you want after mounting underneath. Keep in mind there’s only 3 inch height difference between the pancake and the 5 gal HB tank. You need to consider that the pancake ports are all facing down so think of the space needed for your hoses and fittings.
Also think of exposure to elements and corrosion - a tank mounted underneath your car is in for a much rougher life. Both the pancake and the 5 gal are steel units, and even though they’re coated they will definitely rust.
Thanks for all your help bro.
The wife feels the tank is a missle, if we get rear ended it could easily shoot straight into the back seat or us in front. With that being said I think my best bet is going under the cab. If that tank works I might visit the idea. I have to mock it up somehow, wish I had something the size of the 5 gallon and mock it up under there.
That tank aint no missile (not enough air) - especially if you fill it to 150psi and have it bolted to the chassis. Good ol’ steel tanks - tough as nails. If you’re ever unlucky enough to be in a major accident where the car behind comes through to the back seat, you’ve got other things to worry about rather than a small air tank. The hoses or fittings will break long before the tank ruptures. In the midst of the crash you wouldn’t even notice. It goes whoosh-fizz (show’s over & done!). I’ve had a fitting explode right next to my ear on a 5 gallon tank at 200 psi (don’t ask) … and I’m fine I tells ya. Hey … say whaaat?, sorry I’m a bit hard of hearing. Never mind, … so that’s all good then? Nothing to worry about. 
She was just worried about the tank being struck from behind and shoved into the back seat etc, that’s a 20lb object that will get catapulted into us/kids seat. I won’t win this one, I might as well just consider using the pancake tank under the jeep.
Are there any others that are more “low profile” that’ll fit well under the cab and have good ground clearance still?
If not enough clearance, I’ll just have to jack the jeep up higher than it already is!
I have a JK 2016 and I relocated the evap system and put a tank here. Tank is 8 gals. 8" x 40"
The tank and the air horns are a good safe bet.
The children on the other hand are another story…
Grade 8 bolts will solve any missile situation, and the brass fittings will pop free from the tank sooner than the tank would turn into a missile.
Also, remember it’s only 5 gallons of air. You’re not building something to launch the Space Shuttle.
Check out my install in my signature below, and ask away.
-Kris