Many L guys say its so much easie to just pull the bed rather than dropping the tank. After debating this, and deciding to just drop the tank while the truck was in the air for the trans swap anyway, I cant see how it can get much easier than this!

Yank the bed...still have to disconnect the fuel filler neck, have to disconnect the taillight wiring harness, have to unbolt the bumper, have to pull the bedrug up to unbolt the bed bolts, then have to slide the bed back on the frame, and need at least 2 people to do this, then unplug the lines and harnesses, and swap the assembly out.

Drop the tank...disconnect the filler neck, jack the truck up, put a tranny jack under the tank, unbolt the 2 straps, lower the tank 1/2 way, unplug the pumps & lines, finish dropping the tank, and swap the assembly, easily a 1 person job.

All the talk about it being a PITA to drop the tank and easier to pull the bed had me worried, but after doing it once i'd have no problems dropping the tank again, its a peice of cake! waaaayyyy easier than when i had to drop the tank on my 85 when i converted that over to EFI.

Now for the how-to with pics!!!


Step 1: Unbolt the 3 bolts from the filler neck (7 or 8 mm IIRC)



Step 2: Undo this hoseclamp under the lip under the bed...it slides onto a little metal piece that holds the filler neck up against the bed



Step 2b: Reach over the frame rail and undo the 2 hose clamps for the filler neck and vent tube. a nut driver is best for undoing hose clamps, alot easier than a flatblade screwdriver. after they are lose, reach over and pop the hoses off.
WARNING: excessive burnouts will lead to a huge buildup of rubber powder accumulating on top of the gas tank



Step 3: Its worth the 40 bucks at Costco to pick up a transmission jack! you'll find plenty of uses for it after this, so its money well spent. big flat surface area with a built in ratcheting strap to secure the tank down, but if you dont have one or cant find one, a floor jack with a board across the top will work fine as well, just a bit more balancing required. I had TWENTY gallons of fuel in my tank, and it was no problem at all with the trans jack.

Removing the DS is optional. Makes working room a LOT easier under there. Its four 12mm 12 point bolts on the rear on a 00/01 HD, or four 12 mm 12 point bolts on the rear and two 13 mm 6 point bolts on the carrier bearing on a 02/03 HD. Literally 5 minutes or less to pop out and pop back in. perfect time to polish your aluminum shaft or paint your rusty steel 2 piece shaft! (or install your pimpy CF shaft )



Step 4: Lower tank 1/2 way down, disconnect all the lines & plugs, then lower the rest of the way



Step 4a: Front connections to disconnect. 2 fuel lines (feed & return)...use fuel line removal tools to pop these off, then the front evap connection. i tried to pop the hoses off but they werent budging, i found it easier to rotate it 90* CCW and they pop right out



Step 4b: Rear connections to disconnect. another evap connection, same as front. The electrical plug has enough slack in the cable you dont have to disconnect it. And you can see the 2 upper hoses you need to disconnect from Step 2b



Step 5: Undo the six 8mm bolts holding the pump assembly in the tank
WARNING: make sure you clean the top of the tank off so no dirt or burnout powder falls in the tank!!!



Step 6: The gasket is sticky so it may take a screwdriver or some prying to pop the pump assembly out of the tank. Slowly lift it out, have some rags ready to catch the dripping gas if you've got any fuel in the tank, and put it on the bench for swapping pumps.

Here's a side by side shot with my stock single pump assembly next to my stock dual pump assembly



Step 7: Swapping stock 130 lph pumps with Walbro High Pressure 255 lph pumps from BigBill

The Walbro's come with new rubber sleeves, new gasket, new hose, new hose clamps, new filters, and one part i got extra was a SS 5/16th Y fitting. The stock plastic one can get crushed VERY easily, and starve the fuel system = BAD NEWS! SS ones go for 20-30 bucks, I snagged mine for free, but its worth the price for the piece of mind. 5/16 SS Y's are harder to find, so 3/8th will work, but its just a little harder to fit the 5/16 hose onto.



Suck Gas and Haulin A$$!



Filters - The new filters the walbro comes with seem like they will flow a lot more than stock. the stock ones have plastic molding blocking off some of the filter element, and the walbro filters have something inside to keep the filter puffed out for the most surface area, the stock ones get sucked flat and restrict suction



Step 8: Swap out Pumps, hose, filter, Y, etc. I'm not going to go into detail here, the Walbro's come with good instructions that explain it all. Basically unscrew the clamp holding the pumps on, undo the hose clamps on the hoses and Y, cut new hose to lenght, put new hose and Y in, put walbro's back in and pump clamp. snap new filters back onto bottoms of pumps. I found the rubber insulators with the walbros too thick to fit under the stock pump clamp so i reused the stock pump insulators



Step 9: Completed Pump Assembly, stick on new gasket, drop in tank, rebolt back up, and reverse instructions for putting the tank back up. easy mod!



any questions just post up!