'79 GMC Sierra Grande P/U- gas tank mod.?


#1

Has anyone had any exper.in reinforcing/re-locating this gas tank? I know its in a dangerous location–my neighbor still drives his “as is”-this is a great truck (tho not"P.C."to drive!)it has 300,000 miles on a rebuilt 350 i hardly ever drive it-its a dilemma whether to sell it or not becse of the tank but then someone else would be driving a dangerous vehicle! I-was told the tank could be moved to between the rear frame–any ideas about this??


#2

Was this the infamous “side-saddle” gas tank design? One thing to keep in mind is that the crash test films shown all over the news (and probably to the juries) were rigged with pyrotechnics to ensure a spectacular fireball. I wouldn’t panic over them. That said, if you still want to do something about it, I’m sure it can be done for enough money. I have no idea if there is room to install new tanks inboard of the frame rails (where the driveshaft is). Maybe behind the rear axle (is that “between the rear frame”?)? Maybe a tank within the pickup bed (above the frame), right behind the cab? Just make sure it’s heavy enough not to be penetrated by any cargo you carry. Perhaps the existing tanks can have some “armoring” by bolting 1/4 inch plate to the side, front, and beneath each tank? (You wouldn’t bolt into the tanks themselves, but attach the armor to the frame and bed.) I guess the idea would be to keep the tank from being crushed and split open, or penetrated by something, and if worst comes to worst, the gas spews to the rear, away from the cab.

As I said, don’t let those doctored films panic you into spending a lot of money on an old truck. Do you use the truck enough that you feel your exposure is too high? Have you done research on impartial statistics (National Highway Safety Institute, National Transportation Safety Board, etc.) to see if they consider these trucks high risk?


#3

If the tank isn’t in the cab, you probably don’t have to worry. A tank system can be changed without major problems on your truck if you want too.


#4

The tank met all standards for 1979. I would drive the truck and enjoy it as it is. If you are concerned about your personal safety, get rid of it and buy something newer with air bags. All older vehicles are less safe than the newer ones, it is pretty difficult to modify it, and without crash testing the truck, you would never know if your modifications were successful.


#5

well if safety is your main concern then sell it.if you go do a search on wikipedia you’ll find that since that design was introduced in 73 around 2,000 or so people have died in crashes related to the gas tanks placement.and if your worried about the buyer then inform them about side-saddles im sure there are a lot of people out there like me who will risk it for such a great style truck.

                                                                      -By a proud owner of old gm iron