Difference between AC Delco Fuel Pumps; MU1639 vs MU2294

[mattt]

Is there an actual difference between the two? They are both listed for an 04 Tahoe, with the 2294 being called out for a Z(flex fuel) engine. Is there an actual difference or just different #'s? I see the 2294 is part of the Professional AC Delco line and I think the other is considered OEM replacement?

My 04 Tahoe is a Z 5.3, at least for a few more weeks until the 6.0 is fully assembled and dropped in place of the 5.3, Z engine.

Thanks.

 

[wjburken]

Is there an actual difference between the two? They are both listed for an 04 Tahoe, with the 2294 being called out for a Z(flex fuel) engine. Is there an actual difference or just different #'s? I see the 2294 is part of the Professional AC Delco line and I think the other is considered OEM replacement?

My 04 Tahoe is a Z 5.3, at least for a few more weeks until the 6.0 is fully assembled and dropped in place of the 5.3, Z engine.

Thanks.

There is a difference in pumps made for flex fuel and ones not.

Stay away from anything from AC Delco’s Professional line of products. That is their lowest quality stuff,

 

[mattt]

Thanks. Do you know what the difference is between flex fuel and non flex fuel pumps?

The MU2294 pump is Professional line and the only ACDelco pump listed for a Flex fuel Tahoe.

https://www.rockauto.com/en/catalog...fuel+&+air,fuel+pump+&+housing+assembly,10147

 

[wjburken]

Thanks. Do you know what the difference is between flex fuel and non flex fuel pumps?

The MU2294 pump is Professional line and the only ACDelco pump listed for a Flex fuel Tahoe.

https://www.rockauto.com/en/catalog...fuel+&+air,fuel+pump+&+housing+assembly,10147

I’m not 100% sure, but I think has to do with the fuel pressures that flex vs non flex systems operate at.

 

[swathdiver]

I'm speculating but the difference may be that the FlexFuel pump is bigger, meaning it has the ability to delivery more volume. I don't think you'll mess anything up using it but would google around first to make sure.

ACDelco Professional is one step below GM OE. Sometimes the only option is Professional or there is no difference between the two. The one I avoid is ACDelco Advantage.

 

[wjburken]

I'm speculating but the difference may be that the FlexFuel pump is bigger, meaning it has the ability to delivery more volume. I don't think you'll mess anything up using it but would google around first to make sure.

ACDelco Professional is one step below GM OE. Sometimes the only option is Professional or there is no difference between the two. The one I avoid is ACDelco Advantage.

I got the quality levels of AC Delco Professional and Advantage lines mixed up. Thank you for the clarification.

 

[OR VietVet]

Is the new fuel pump going to be compatible with the 6.0 engine?

 

[S33k3r]

I don't know about volume of flow, but it is my understanding that the flex fuel pumps are designed to be more resistant to the destructiveness of alcohol. Alcohol tens to be very ******* all the soft parts of your engine.

 

[Fless]

The AC Delco "Professional" line is apparently now being called the "Gold" line.

 

[mattt]

Thanks all. It's interesting that the only fuel pump listed for a flex fuel Z engine is the Professional with no listing for GM Original OEM. Am I missing something here?

All GMT800 SUV's Tahoe/Escalade/Yukon(Denali & Std) use the same fuel pump(MU-1639), so no problem there. The only different one is the flex fuel 5.3 Z engine, MU-2294.

I'd just like to know definitively what the difference is. I may have to buy both, then return the one I don't use. My original 04 fuel pump w/ 324k on it is still working(shocking I know), but it does get finicky if the vehicle sits for a few days. After sitting a few days without starting, it doesn't like to pump, unless you whack the fuel pump a few times with a rubber mallet. That is a classic sign of a fuel pump getting ready to give up the ghost. My 01 2500HD CCLB used to do the same thing every so often before I replaced it. A tow truck driver of all people taught me the whack the tank trick when I was stuck at Lake Havasu with a non-starting truck. He whacked the tank and I drove the truck home and did the fuel pump once home. So I'm pre-emptively replacing this Tahoe pump during the swap.