I have recently completed retrofitting my 23 gallon tank to the 33 gallon tank. This was a bit more involved than I originally thought, and I had a few issues along the way. I want to thank Dixit for answering many questions and posting great detailed pics of the installation. I will not be re-posting pics, since his documentation is so thorough. I do want to list all the parts needed to convert a 23 gallon tank to a 33 gallon tank and document one major issue:
Here is all the part numbers needed to retrofit the 33 gallon tank into a truck that was originally purchased with a 23 gallon tank:
* PN 68408875AC - 33 gallon Tank
* PN 5203045AB - Strap. This is a third strap that has to be added to the 33 gal tank. The other two straps from the 23 gallon get removed. The bracket that the strap goes into may or not be there. Dixit had this bracket on his truck, but mine did not. I recently stopped at a dealership and none of the 26 gal or 23 gal tank trucks had this. I plan on fabricating a bracket in order to put this third strap on. Right now, I am running the truck with about 1/2 a tank of fuel until I get this done. The attached pic has the bracket needed circled in red.
* PN 52029908AB - this is a hose is shorter and connects to 52030443AB
* PN 52030443AB Vent line
* PN 68307831AA - Vapor tube
* PN 52029888AC - Vapor Canister. The larger tank uses a larger vapor canister
* PN 52029909AC - Vent Hose
* PN 6104717AA - nut to connect third tank strap
* PN 68409160AD - Fuel pump. The 33 gallon tank requires this fuel pump and is a different pn than the one in the 23 gallon tank.
All in all it was not extremely difficult to do the swap. I did it with the help of a friend and a lift in about 3 hours. However, double check all your parts ahead of time. I put all the the parts that get fixed to the tank on ahead of time. In doing so, I found that one of the hoses had the correct part number tagged on the part, but the part was not correct. I had to order another, and this time, it came in correct. I was told incorrectly labeled parts are not uncommon. Cost is the biggest issue. When I first decided to do this, I thought there was only going to be about $600 in parts. That was until I found out I needed a new canister and fuel pump. It ended up costing about $1,200 and that is with a 25% discount from my dealer. Before you order parts, look on line or talk to your parts guy for a discount. The other big issue is the missing frame bracket for the third strap. I am really surprised that they did not just include this on all the trucks. It's not a huge issue, as there are ways to do it, but it is an added problem that I did not expect. Best advice is to order the truck with the 33 gallon tank. Good luck.