I wanted to leave some of my experience with rear mounted gas tanks for the next person who comes along and needs it.
I have a '54 3600 and the frame sits narrower in the rear than the 3100 making it really difficult to find tanks to fit that aren't fully custom. Add in a TCI 4-link rear suspension and things got even tighter.
So here are a couple of options:
1. Suzuki sidekick tank ($99 or so) fits very well between the rear rails without any modification. The difficulty I had was that if you wanted to put in anything other than suzuki components- ie fuel pickup or sending unit you really run into difficulties. The screw hole mounting for the pickup or sending unit don't work with any of the non-suzuki parts I had bought (which have standard spacing). I had a lot of time swearing and screwing up things before I eventually cut the tank to install a 3/8 pickup tube. The resulting mess lead me to scrap the idea.
2. Boyd Welding 30x12x12 Universal Tank ($250) -The lower section of the rear frame rail sits at 29" meanwhile the upper section is wider. This tank is 30" , I removed just over 1/2" from each side of the lower rail and the tank fits in perfectly. I fabbed up some mounts and I couldn't be happier with the end result. Is it more expensive? Initially yes, but by the time you're done messing with the suzuki tank you're not going to be far off. I wish I had done this from the start, it would've saved me many hours of research and messing around and pointless money spent trying to fit a round peg in a square hole.
I will say if you go with stock suzuki parts for the pickup and sending unit, you'll be very happy and it'll be cheaper. If you want to have 3/8 line and more custom features that come standard in the aftermarket world, Boyds universal tank was the way to go.
Hope this helps anyone with the 3600 looking in the future. I'm sure there are other options out there, just wanted to share my experience with two of them.
Last edited by Montana 54 Chevy; 04/01/202110:27 AM.
This looks great. What parts did you use for the side fill extension? I would like to do that too. Plus the make an EFI version of that tank! Pricey though
1951 Chevy 3100 "Project for my Wife" - Jigsaw Puzzle 1969 Camaro SS350 convertible 1969 Camaro 327 convertible
The filler hose is Gates 24718. I have the older Dakota Digital gauges, they're programable so I don't anticipate any issues with the sender. I'm still working on the suspension and rewiring it right now. As far as the tank, yeah, the EFI version is pricey. Hoping that this one will work ok w/o the baffle. I had a 72 blazer tank on it initially that wasn't baffled and didn't have any problems with fuel starvation. Only reason I switched to the mustang was because after lowering it, the tank was too close to the ground to me. The stang has a much lower profile and looks like it will work out nicely.
Last edited by Mobileortho; 04/22/20214:45 PM.
Robert C. If it's true what they say, "You learn from your mistakes," I'm a Genius in the making.
Robert, thanks for your comments. I've been planning to put the tank under the rear of my 37 pickup but don't want to have one that hangs down making it look like its got hemmroids. I looked at the mustang tank a while back and you confirm it sits a little higher. I don't need a 25 gal tank!!
