A quality aftermarket part should fit as well as the oe part. It's the el cheapo "value" parts that are usually a 'make it fit' operation.
My experience with Airtex has been poor. I replaced the fuel pump (along with the strainer and fuel filter) in my previous Protege and it failed in three months, and the warranty replacement one started whining right after replacement. I'm unsure if that one failed prematurely, as I sold the car.
Airtex is junk. After you warranty out your pump a couple times I'm sure you will just buy a better one anyway. I have definately had better luck with the precision branded (carter) fuel pumps I've sold from Oreillys than the airtex brand ones which had ALOT of wty claims.
The carter pump in my old Buick made it three months. The Airtex made it past the one year warranty by a day. I won't buy carter ever again (airtex either for that mater)
ACDelco or Delphi only no exceptions if you plan to keep the truck for many years. Delphi is the OEM pump. DELPHI Part # FG0053 is for non flex fuel (dont know what yours is) and costs $161.79 on rockauto. The flex fuel version is $302 http://www.rockauto.com/catalog/moreinfo.php?pk=1112133&cc=1399507
I have trouble getting any of my customers to consider an Airtex. They have had too many failures and don't like doing the job twice (or three times) and only getting paid once. A lifetime warranty on a fuel pump usually is given by a company that is trying to overcome previous issues with their pumps. Doesn't mean they've fixed the problem - just means they are hoping to sell more pumps. Delphi is not part of GM (not since the 90's). Delphi does make SOME GM fuel pumps - but those pumps are sold under the GM or ACDelco label. An ACDelco fuel pump is built to the exact specs that GM has for the pump. A Delphi that was OE is also built to those same specs. But Delphi can't make the same exact pump and put their own name on it without violating their agreement with GM. Now having said that - they can make a minor irrelevant change and probably get away with it. But any pump that they are not the OE supplier - they are forced to reengineer on their own - just like all the aftermarket suppliers. If Delphi was the OE pump manufacturer on the original pump, but are not the current supplier for GM replacements, they don't have access to any improvements to the OE design. GM does look at pattern failures and institutes changes to parts all the time. Unless you know that Delphi is STILL the current OE manufacturer for the pump you are looking for - it is not the same as the ACDelco/GM part.
Obviously, any brand can have premature failures but the Airtex in our Caravan crapped out in 2 years and about 25,000 miles.
Well, against some recommendations from you guys, I bought a Bosch unit. Father-in-law said they've had great success with them for customers' vehicles. Been using them for about a year....mainly because they're almost always available when they need them fast. Haven't had one to come back yet. It was a direct plug in....didn't have to splice/solder any harnesses. Pump is as quiet as the OE unit. Entire swap took about 45 min. Unbolted the bed and just lifted up the driver side enough to access the pump/unit and supported it with some 2X4's we had that just happened to be the perfect length. Everything was within easy reach. So, if it fails, I know it won't be much of a hassle to do again. It wasn't near as bad of a job as I thought it would be.