This thing is about to end me!!

OK, so about three months ago I started to notice a gas smell and small puddle underneath my runner. Upon further inspection I found that I had a small crack in my gas tank and a slow leak. I figured I had done something stupid somehow to crack it (offroad and what not), although the skid plate had been on the whole time and wasn't bent. Fine. So I took the tank off cleaned it out and had a plate welded on the bottom to stop the leak, put the tank back on and off we go... wrong. Two weeks later the thing starts leaking again, another crack from a spot two inches away. WTF!? Fine. So the tank is 10 years old, let's just get a replacement tank. Searched around and found a new tank at a decent price, ordered and installed and off we go... wrong again. Two f'ing weeks later it started to leak from almost the same spot!!! Checked the skid, no rubbing. Haven't been off road, don't see how it could've been hit. Called the company and they said it could've been defective, sent another one no charge. Installed and off we go... wrong again! This is the second replacement tank I've put on and it's leaking after being on the truck for 2-3 weeks!! Can anybody please tell me what's going on/what you would do here. This is really ticking me off!
Help.

 

Go to Home Depot and buy one of their $50, night vision, color mini cams. Take it home, mount it somewhere outside out of sight (preferably when no one is around) pointing at where you park your ride, hook it to your TV and VCR, pop in a tape and wait for the vandal to show up... good hunting !

 

I'm really starting to wonder if somebody's sneaking over and beating it with a hammer or something. Although it doesn't show any damage other than the crack.

 

Maybe part of the skid is rubbing or poking a hole in it.

 

To this end... if the skid plate is not securely mounted it could be banging against the bottom of the tank as you go down the road - but - one would think that you would hear that, that is, unless you constantly jam your music too loud to hear.

 

Is the tank in a bind at all? If it is; then it may crack from stress. That could explain why the other tanks cracked in the same spot.

 

Didn't seem to be any binding. Took a little wiggling to get them in and out, to avoid the driveshaft and all, but no major cranking. The skid plate has 0.5-1" of clearance all the way around and isn't rubbing as far as I can tell. grrrr...

 

ok "if" it is rubbing, you should try and paint the tank or the skid (use a color that will show up well) and put it on and run it for a while then remove it and see if any has rubbed off on the other one. Or maybe try not running a skid at all for a while.


I really dont think that is it though, because it is cracked and doesnt have a hole in it.
"maybe" it is a coincidence that all 3 tanks have had a crack in them.
Do you have any pics of the crack? Maybe that would help us to figure out what is happening.

 

No pics at the moment, I'll try and remember to take some next time I'm at home. The area is the lower most section of the tank (I think), and it has these 6 or 8 little round indentions on it. As I remember they were connected to something on the inside of the tank but I don't remember what it was or its purpouse. I wonder if when they made the tanks they simply made that area too thin because of those indention things or what... I don't think it's the skid because after we put the first replacement tank on I left the skid off in case I needed to get back under and fool around with it, which I did...

 

Is there anything protruding from the top of the tank that is getting tweaked? If that something (ie fuel pump, etc) is welding/mounted to the bottom of the tank for those indentations you see, maybe its actually flex/interference on the top of the tank thats pushing/pulling on the bottom to cause the crack.

 

Another thing I just thought of- how hot has it been in GA lately? Just wondering if your tank is properly vented so as to not allow pressure/vacuum buildup inside. This would also cause stress fractures.

 

With that many problems with the gas tank I would be watching where you park it at home and anywhere else you take it on a reguler bases. Gas tanks don't leak like that one after the other.