I finally broke down and purchased a 20 gallon mustang fuel tank to put under the bed of my '57 GMC 100. Can I tweek the original GMC fuel sending unit somehow to use it in the mustang tank or do I need to purchase a mustang or other sending unit and change the signal somehow? As I understand it, the mustang fuel tank sending have a resistance range of around 10 ohms full and 73 ohms empty. The '57 GMC fuel guage requires a resistance range of around 30 ohms full and 0 ohms empty. Thank you in advance for your help. Nate
Nate, I have heard of guys modifying the sender. I tried on mine, and it worked for a while, before breaking. I ended up just using a small guage setup for the ford sender, and put it in an not so obvious place. I keep thinking I may try again. I have not seen any custom senders for the mustang tank, but who knows, they may be out there. Good luck.....Mike
I hack-sawed off the sending unit and a few inches of the tube that it is spot welded to from my '57 GMC. Using really small radiator hose clamps, I attached it to the tube in the mid-80's Mazda pickup tank I mounted under my bed. Did a little bending of the GMC float arm to get "full" and "empty" in about the right place and buttoned it up. Worked well for two weeks and then read always empty. Turned out the float had a small leak. It eventually filled with gasoline and sunk. Removed and drained the float. Soldered up the hole and put it back together. Been working well since last summer.
I know one of the issues with the sender, was it works basically backwards from the stock one. The mustang unit mounts under the tank. With some creativity, it should be possible. I didn't feel like messing with it at the time, but am thinking about trying again. I will let you know if I decide to....Mike
Nate, I'm in the same boat with the Mustang gas tank. I've got the proper ford sending unit in the tank and I think I'm going to do a custom gauge cluster so I can just get the gauge to match. If you want to keep your original cluster you could just mount a new gas gauge on the dash somewhere. A gauge will run you around $40-50 depending on the make.
Hey If you have pictures of your gas tank install I would really like to see them, as i have bought a 16 gallon mustang gas tank to use in my 55 project, and now realize it is way to big for the frame. any help would be nice. Thanks Brad
Mustang tank I don't know how to post pics but what I did was build a 1" x 1" sq tube frame and bolt the tank into it and attach the 1 x 1 just frame below the truck frame with pieces of 1/4 x 1 flat. Bolt it to the truck frame (not weld) or you won't be able to remove the tank in the future.
heythanks 57 restomod for the info. so you just made a 1x1 frame and screwded the tank to it and bolted it to the bottom of the frame rails. how far back is the tank mounted, and it won't scrape the groung will it. thx brad
Top of the Mustang gas tank sits about 1/4" below the bottom of the frame. There's plenty of clearance to the ground. The rear of the tank is about 4" ahead of the very back of the frame. I've got my suspension lower than stock and there's no way I have room for tailpipes to go over the axle and under the tank so I ran my tail pipes out in front of the back wheels.
sending units I am on my second Gas sending unit 55,,,The first one did not work..and the second one did not work.....So I will be stopping at the Gas station everytime i go for a ride to top it off. I got tired of taking off the the Speedometer Bezzle...
