Hi. It is very difficult to pump gas into my 2005 gmc sierra sle pickup truck; please help!

okay you've a vent valve or purge valve who's electrical connection has been schmeared~ or perhaps it's a vacuum connection....anyways look near the tank for physical damage to the vent valve or the purge valve...one of these ain't workin' right~ will look for a cartoon or utube~

http://www.amazon.com/ACDelco-214-2149-Professional-Canister- Solenoid/dp/B001KSCSQU/ref=cm_cr_pr_product_top

vacuum and electrical....whew~

and only 11.96~

Do you live in a state with the new gas nozzles that require physical pressure to push them in to make a secure seal? These new style nozzles (identified by the complex rubber gasket around the nozzle pipe) are there to prevent escaping fumes from entering the atmosphere and your lungs- that's a good thing- but they are harder to use when refueling- if you are using the old style nozzles (like here in New Mexico) I would guess that it's just that dumb GM design where they really don't know how to curve their filler pipes to match the curves on the gas nozzles- just a guess, but there may not be anything wrong other than trying different angles of approach and levels of penetration- damn, this sounds sexy