I couldn't find any useful information to point me in the right direction. I have a titan 52gal fuel tank in my 2003 and have a slow fill issue due to small hose/fillerneck set up. I have the new generation Titan tank if anyone's wondering. Anyway, I tried to order Transfer Flow's GM retrofit fill neck kit(per Titan's rep's advice), but of course, they refused to sell me one because I have the 52 gal Titan tank. Maybe I should have lied to them in the first place. Man am I confused---first the Titan rep tells me to order this and now the refusal because I have a Titan tank? Huh? Anyway, this is the first time I encountered this kind of refusal over a very silly liability concern. I asked them point blank to give me a liability disclosure agreement and I'd sign them if it was what it took to get them to sell me the kit I needed--no go. Yikes.

So here goes looking for another solution. I know the LLY and newer equipped Duramaxes have the larger system but their $600+ from GM! I have a couple salvage yards keeping an eye out for a salvaged set but no luck so far at this point. I was wondering if there is another simple solution that anyone of you might shed some light?

Does your tank have a provision for a vent line? The reason I ask is because when I had an 03' I modified the stock filler neck to accept the large nozzle, but you must add an external vent line for it to work right. I used a 3/4" rubber line from the top of the tank to a fitting that was brazed into the stock filler neck. When I'd pump fuel the vapors from the tank were introduced into the filler above the level of the fuel pump nozzle so that they wouldn't create a backpressure and kick the pump off. The small fill line in the center of the stock filler neck just needs to be punched out with a chisel to make it physically large enough for the big nozzle.