A water pump, as you probably know, is one of the key components for keeping an engine operating at optimum temperatures and although it is largely a solid piece of machinery, it could go wrong or wear out over time. Now it isn’t rocket science to work on a nonfunctioning water pump but sometimes it’s just easier to get a new one, especially if it’s for something as durable as a 5.9L Cummins motor.
What’s the best 5.9 Cummins water pump for your truck, then? Check out this review and we’ll help you decide which one of these powerful devices is the right one for you.
If you’re curious about how to prevent water pump failures or how to tell if your water pump is about to fail, we also have some tips at the end of the article.
- Our Recommendations
- Value Champ: ACDelco 252-318 Professional Water Pump Kit
- Fast Mover: Gates 43034 Water Pump
- Consumer Favorite: Gates 43526 Water Pump
- Simple but Effective: OAW CR3072 Engine Water Pump
- Versatile with OEM Quality: Airtex AW6158 Engine Water Pump
- Final thoughts on the Best Water Pump for 5.9 Cummins
Value Champ: ACDelco 252-318 Professional Water Pump Kit
- All Makes water pumps fit GM vehicles as well as a wide range of non-GM vehicles
- Thoroughly tested for reliable, leak-free performance
- Coated seals support seal longevity and durability
- Heat-treated shaft assemblies provide superior strength and durability over non-treated assemblies
- High-quality bearings are permanently sealed and lubricated for greater durability and long life
This 5.9 Cummins water pump upgrade by ACDelco comes with a full kit including the main pump and the components such as gaskets, seals, and O-rings needed for installation. The ACDelco 252-318 is our current value champ. It’s also priced reasonably since it promises an OE level of fitment.
Suitable for a wide range of applications
ACDelco’s 252-318 pump kit can be fitted to a wide range of trucks powered by a 5.9L Cummins including the Dodge D250 (1989-1993), D350 (1989-1993), Ram 2500 (1994-2009), Ram 3500 (1994-2007), W250 (1989-1993) and W350 (1989-1993). Is there any installation hassle? The kit comes with a square cross-section O ring gasket which means bolting on the new pump is fairly straightforward.
What do we think of it?
The ACDelco 252-318 is among the good quality water pump replacements out there, one that features solidly put together bearings that are permanently sealed and lubricated for durability. It is also among the easiest applications to install given that most of the buyers have found it to be simple to work with.
- Suitable for a wide range of trucks
- Durable for the price
- Gasket provided isn’t of the highest quality
Fast Mover: Gates 43034 Water Pump
- Gates 43034
Gates’ 43034 model has proved to be a popular choice when it comes to 5.9 Cummins water pump replacement. Based on how often this product is low in stock, it sure is a fast mover, and for good reasons. Made of high-quality aluminum and steel, this water pump’s impeller is also made of metal, making the whole thing quite resilient. If you drive a Dodge B-Series (93-03), W250 (89-93), W350 (89-93), Ram 2500 (94-03) or a Ram 3500 (94-03), this aftermarket option is for you.
Packed with all essential replacement components
This 43034 model comes with a host of components including the gasket, a steel tube, and a rubber O ring seal, to complete the fitment. The bypass steel tube, in particular, is a nice add-on that you’ll like.
What do we think of it?
Gates’ 43034 water pump represents good value and if the past is any indication, it remains durable through the years. As an OE-equivalent water pump for 5.9L Cummins, it meets the majority of the buyers’ expectations and does a decent job of moving the coolant throughout the motor to ensure it stays at optimal operating temperature.
- Easy to install
- Proven reliability
Consumer Favorite: Gates 43526 Water Pump
- Gates Engine Water Pump 43526
Gates is known for making reasonably priced quality pumps and this 43526 model is no different. It is one of the highest-selling replacement pumps for 5.9L Cummins and is currently a consumer favorite since its compatible with newer versions of the Dodge Ram 2500 and Ram 3500 from 1998 to 2009.
Benefitting from solid construction, this particular water pump is known to work perfectly with 5.9L Cummins as it bolts straight up with no interference or alteration.
Closest to factory construction
The biggest highlight of this aftermarket water pump is the fact that it looks just like the factory Cummins unit. Other than a slightly modified weep hole, Gates’ 43526 model is quite similar to the factory spec in terms of the impeller design, blade count, and the all-important build quality. Interestingly, the OEM water pump from Cummins is notorious for wearing out rather quickly and as a result, a lot of users tend to opt for this Gates alternative for its relatively similar build quality and design.
What do we think of it?
All things considered, Gates’ 43526 model is worth the money you save over the factory water pump by Cummins. Featuring metal fins, as against the plastic fins on the factory pump, it’s actually beefier and feels more solid. Reliability, too, is rock solid and as per our analysis, it’s highly recommended by those who are currently using it.
- Factory-like build
- Most commonly picked
- None, really!
Simple but Effective: OAW CR3072 Engine Water Pump
- Brand New (Not Remanufactured) Parts
- OE Original Fit and Performance
- Gasket Included
- One Year Warranty / 30 Days Return Policy
- Interchangeable with GMB 120-3072 and Airtex AW7145
A simple, yet good, quality replacement for your old, worn-out 5.9 Cummins water pump, the OAW CR3072 is quite basic in its construction. That said, it does the job and is just as effective as all the other products listed here, thanks to its factory-like fitment and carbon ceramic seals for improved coolant flow. As for compatibility, you can get this pump fitted to 1993 and 1994 model Ford F700, F800 (1994-1996 and 1998), Dodge Ram 2500 (1994-2006) or Ram 3500 (1994-2007).
Leaning on the expensive side of things
OAW’s offering for a traditional 5.9L Cummins user is a textbook OEM-inspired water pump, but at $39 a pop, it isn’t exactly budget-friendly. The premium over others is down to the fact this pump uses high-quality carbon graphite ceramic seals to reduce the odds of any leaks whatsoever. So if you are someone looking for that perfect seal, this particular option might just be worth the higher price.
What do we think of it?
OAW has talked about the CR3072 in great detail about how efficiently it maintains the coolant flow and how there are no compromises. However, it seems this model sits pretty low on the buyers’ market. What’s more, some of the buyers reportedly have received the pump without a gasket despite the packaging stating otherwise.
- OEM fit
- Uses top quality ceramic seals
- Basic construction
Versatile with OEM Quality: Airtex AW6158 Engine Water Pump
- This pump is used on accessory belt driven applications
- All gaskets or seals necessary for installation are supplied with pump
- Durable housing features precisely-machined mounting surfaces for proper sealing
- The latest impeller upgrades engineered for maximum coolant flow
- Read and follow all enclosed instructions to maximize pump life and validate warranty
This is by far the most expensive water pump we have listed here. It does rely on its sturdy construction, which is always good news for a Cummins owner. In fact, the Airtex AQ6158 features heavy-duty unitized bearings and seals for use in robust applications. The metal impeller, too, has been re-engineered for more coolant flow.
Heavy-duty design that’s fit for multiple applications
Like the ACDelco 252-318 listed above, this engine water pump by Airtex can be fitted to all ISB series Cummins engines including the newer Dodge Ram Series (2002-2009), Ford F650 and F750 from 2000 to 2008 and L8501 model from 1998, although given its spec, it makes sense to splurge extra on the Airtex only if you need faster water flow under heavy load.
What do we think of it?
Is it the best water pump for a 5.9 Cummins? For someone who likes to put their truck through heavy usage like load-lugging under harsh weather conditions, the Airtex certainly is among the best options out there. Sure, it’s a little expensive but it’s also more likely to survive over the years thanks to its solid build.
- Perfect for heavy usage
- Can be fitted to several applications
- Little expensive
Final thoughts on the Best Water Pump for 5.9 Cummins
For those hot summer days when your Cummins motor needs a steady flow of coolant to keep its running fine, a water pump is crucial and if the latter fails, it could lead to an engine catastrophe. Fortunately, each of these replacement water pumps listed on this page are the right fit for your old 5.9L Cummins motor.
The OAW CR3072, for instance, is a classic aftermarket solution, however, it is priced noticeably higher for a seemingly similar construction compared to the others. Airtex’s AW6158, on the other hand, has a solid build and is aimed at those with heavy-duty trucks, but it’s also the most expensive water pump of the lot. Gates 43034, on the other hand, has consistently proven to be a great value and durable but it’s the ACDelco 252-318 Professional Water Pump Kit that offers OEM level of fitment and high-quality impeller and bearings for the least amount of money. Ultimately, it’s the consumer favorite, Gates 43526, that also happens to be our pick for the best water pump for 5.9 Cummins motor. It mimics the factory Cummins pump for construction yet it feels more solid despite costing considerably less.
How To Know If Your Water Pump Needs A Replacement Soon
Here’s how you can find out about an impending water pump failure:
- Clean the water pump housing, removing all excess dirt and debris.
- Crank up the motor and leave it running to increase engine temperature, and check if the system is pressurized.
- Check for leakage at the water pump outlet housing or the rear cover gasket, and leakage at the water pump vent or weep hole.
- A stain around the weep hole is bearable but if a weep occurs with the engine running and the coolant system pressurized, then the water pump should be replaced.
How You Can Prevent A Water Pump Failure
- Flush your cooling system whenever the water pump is replaced. This will help prevent contamination from entering the system, which may result in repeated failure.
- Inspect the fan blade. If the damage is not detected, bent blades, loose rivets, and cracks may result in premature bearing failure. If there is any visible damage, the next best thing would be to replace the fan.
- Ensure that the engine fan pulley is placed properly on the pump’s shaft. If you notice the fan wobbling while its rotating, the vibration might cause premature bearing wear.
- Inspect the thermostat and radiator cap. Examine your thermostat and radiator cap, and replace if it shows signs of sticking or leaking.