not absolutely nessasary
I think you could use a gas tank for diesel--the only real difference in the 2 is the diesel tank has a different sending unit,it has a water sensor built into it,to light the "water in fuel" light when water accumulates in the tank,they also have a built in siphon hose setup to drain the water,both are nice to have,but not really nessasary in my opinion--if you use the truck often,and fill it frequently,and use a bottle of isopropanol dry gas ocaisionally,and drain your fuel filter once in a while,I doubt you'll have any trouble.....
I dont know how much gas you can mix in with a GM diesel and have no ill effects--I do know one guy who filled a company truck with a 6.2 with gasoline,the truck had dual tanks and he used all but a half a tank of diesel on a long trip,and afraid he wouldnt be able to make it back or get diesel after dark,he stopped at the next station and topped off the tank with regular gas!!--he didnt remember he was driving the diesel company truck until he went to start it up and saw the glow plug light!!!!-
-he called the company,my brother is head of truck maintenence,he asked his boss if he wanted to send a wrecker to get him,or if he should drive the 100 miles each way to drain the tanks and refill it with diesel--his boss asked the owner of the company if they should go rescue him--he said "That truck is a POS anyway--I couldnt even get it started to plow my yard last year--tell him to dive it back---if he doesent make it,then send a ramp truck to get him"!!!---So he drove it over 100 miles with a roughly 50/50 mix of gas and diesel,and the guy at the gas station told him to add a quart of 2 cycle oil for good measure,it not only made it back with no problem,he said it actually ran better than it ever had on the previous trips he made in it--my brother simply topped off both tanks the next day,and that was over 2 years ago,and the truck still runs the same as ever!!.
I had a VW Jetta diesel,VW claims you can use up to 3 gallons of gas per 14 gallon tank in the winter!!-
-many folks add a gallon or so to make them start easier in the winter(most of them are too cheap to fix the glowplugs,and dont like using starting fluid)--havent seen any meltdowns yet,but I cant see it doing a diesel any good running it on gasoline for any length of time--bet it would clean the injectors real good though...
sounds like good info there to me. i am thinking ahead on my work in progress. eventually i will swap something like a CAT 3116 I-6 or a 3208 V-8 into it. it already has dual tanks for the 454 so i figured that may as well use them. I did not think about the water sensors though. or the siphon hose. just things to consider when doing a swap for sure. and when this gets all swapped over how hard is it really to change the sending unit from a diesel tank to the gas? they are the same size I would assume as I know it costs more money to retool your machinces and make a different part for a gas tank... so gm most likely used the same tnaks w/ same sized holes but different sending units.
---anyway,mine lies to me,the "water in fuel" light comes on sometimes,and I drained the tank,and NO WATER came out!
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