very noisey fuel pump

[sjhanlo]

My 2001 Montana just had the fuel pump replaced. It is extremely noisey and very irratating. More importantly, my wife is very mad at me.I had a very good mechanic replace the pump for me. He warned me to only buy a dealer provided pump but when I contacted the dealer they wanted $540. Advance Auto parts wanted $250.
So, I called the company that makes the Advance pump(Airtex) and asked to talk to a tech guy. He told me that they make most of the pumps used in NASCAR and are the OEM for GMC. If fact, he said that the bad pump I am replacing was probably this same pump I was buying.
I cant live with this noise and it is way too expensive to replace my wife. My mechanic says, " I told you so" and Advance and Airtex both say that they are blameless. Any insight would be appreciated. I do a lot of car work and consider myself to me automotively savy. I usually do my own work but this time I didnt feel like messing with all that gas.

[cdru]

I replaced my pump earlier this spring and probably had the exact same noise you had. My pump too was from Advanced, but it was a Master branded pump with a LLT warranty. I would have described the sound as a mechanical whirring noise and constant, not just the normal noise you would hear when it's building pressure up when the key first gets turned on. The noise would resonate in the tank, and thus would also get transfered into the frame of the vehicle.

I did the work myself and while I wasn't thrilled about dropping the tank again, I did. I took it back in to the store and said the noise was unacceptable. The happily replaced it with another one. Comparing the two, there were minor differences in the two. My "faulty" pump had springs on 2 of the 3 supports while the replacement had springs on all 3. The springs also compressed easier, like it was designed not to have to compress as much as the faulty pump. The supply tube was also considerably shorter. There were other cosmetic differences like how the float attached or the color/type of plastic, but that didn't make any difference to me. To me, it looked like my "faulty" pump might have been mislabled and was intended to go in a similar type application with a deeper gas tank. With my shallower tank, it had to compress more to fit in there, exerting more pressure on the tank and all the vibrations then were felt/heard.

If you are handy, it really isn't that hard to drop the tank. There are 3 bolts that hold the straps on, and it just drops down. There are 3 fuel line hoses to disconnect before dropping, as well as the filler tube. Empty, the tank is suprisingly light, obviously it gets heavier the more fuel you leave in it. When I did mine, I had about 5 or 6 gallos of gas left. A transmission jack would make it a snap, although I just used a few blocks of wood at each end and slowly lowered it down one block at a time on each end.