84545446 Emission Reduction Fluid Supply Pump Module

I had been contemplating deleting my truck after a previous pump didn't solve my problem. The pump I needed was for 2017 L5P Duramax engine and this was news to me that diesel trucks needed emissions items that are so expensive. My first replacement pump was purchased on Amazon and after the mess and stench of DEF fluid cleared my truck wasnt fixed and even took it to the dealership to check my work and the pump. Sadly it wasnt fixed and I still had to look a big warning on my dash screen and had to remove that pump, deal with 2.5gals of DEF fluid wasted($21 wasted) and my truck wasnt fixed. The refund and return policy of Amazon is the best but I just wanted my truck fixed. Now I ordered this pump, learned from previous mistake and only put 1 gal into the DEF tank and went for a drive to see if the problem was fixed. Initially the warning was still there, but after about 20mile drive the check engine light was off which was a sign that this pump worked 50% of my problem was solved. I pulled over and the warning was still showing on the dash but no check engine light came back, so I spent another $21 on 2.5gal bottle of DEF fluid(a full tank is 5gal). I waited for about 5mins, turned the key forward without starting the truck and the warning finally disappeared which meant the last thing to do was check the level. Scrolled through the menus(which were not available before) to the DEF level screen and it read"OK". Drove home with no other problems and now I am happy my truck is fixed for now. Update: Code for DEF level came back again along with def heater and my truck went into limp mode in Oct 20203. Now I have a big shiny lawn ornament that is a 2017 GMC Sierra Crew cab Long-bed dually because of this damn DEF pump again and now the truck is speed limited for the same issue.

Perfect fit for 2019 duramax.

My truck is in the shop currently. Was just told that this part is the culprit. It's barely been a year since it was installed. So unless you want to do all of the work to replace it, only to do it again in a year, i wouldn't buy this. That's why it's so cheap compared to other sites.

Just like it said GM Genuine part , it was packaged well and no damage , I installed it right after I received it and everything worked well , cleared the code and its been 2 days and no check engine light .

Installed and truck runs fine now. Had code P1050, after install and clearing the code CEL went away. This part is known to go out fairly often. Hoping I can get good life out of this product.

Great replacement part !! OEM part

Starting to click and tick. I hope it last

Fit as listed 18 Chevy 2500 diesel. Genuine GM part.

I purchased this AC Delco replacement part instead of am aftermarket part. Within less than 2 weeks / 800km of driving the emissions system warning came back on. Thinking it might need ECU reprogramming to acknowledge the new part I took it to the dealer who confirmed that the warning was because of an "internal failure" on this AC Delco replacement heater. Not even worth the time, effort, or hassle, and definitely not worth the purchase price.

Had this heater unit installed at our local GM dealership beginning of January of 2026, and less then 2000 km later it's failed. Late enough so it can't be returned and cannot get any info on if there is warranty or not.