Engine/Transmission (1998.5 - 2002) Water pump upgrade

[jaybo]

I have some great news for everyone about water pumps.

You may have heard my stories about overheat when towing at high power over Loveland pass last summer and some have told me about your experiences with overheat conditions similar to mine on the same grades and conditions i. e. I15 southbound out of Vegas.



I have done considerable research on water pumps for our trucks.

Genos, Gates, and Cummins have three different pumps for:

1. 12 valves from 89 to 98 (Gates part 41181)

2. 24 valves from 98. 5 to 07 (Gates part 43526)

3. 24 valve 6. 7 liter 08 on (Gates part 42291)



I have discovered that the water pump casting area on the block is the same on all of these engines and that any of these pumps will mount on any of these engines. Furthermore, the drive pulleys are indentical in diameter and offset, and the impellers are all the same depth. The mounting bolt holes are identical, the sealing O rings are identical.

Cardone is an aftermarket water pump manufacturer and they build products superior to Gates and OEM (for a little more money); Cardone pumps use roller bearings. Cardone makes only two pumps for all these model year trucks. Model 5531411 is specified for model years 89 to 07 5. 9 liter and model 5531412 for the 6. 7 liter 08 and up.

The 5531411 uses a five blade stamped impeller. The 5531412 uses a 7 blade cast iron machined impeller. The Gates pumps use five blade stamped impellers for both of the 5. 9 engine pumps and a composite (plastic) 7 blade impeller for the 6. 7 liter pump.



Some TDR members reported trouble with the early 6. 7 liter OEM pumps and were substituting 5. 9 liter pumps since 6. 7 liter replacement pumps were in short supply back in 09. In one post a Cummins engineer reported it was ok to use a 5. 9 pump on a 6. 7 engine "in a pinch" but warned that the truck might overheat at altitude under high power output condtions because of reduced water flow. Bells began ringing in my head.



SOOOO, I bought a Cardone 5531412 seven blade 6. 7 liter pump and mounted it on my '99 5. 9 liter bombed engine. It fit perfectly. I figured it would be a good match with my Griffin aftermarket radiator (one gallon extra coolant capacity. )

And the best part. I just returned from a towing trip to Sacramento with my 15,000 lb. 5er and can report the following:

It is difficult to warm the truck up when driving around empty. I have a 190 degree thermostat (stock) and the truck heats up to 180 and no higher. The truck used to get up to 190 right away empty. Now empty it runs 10 degrees cooler. This would no doubt be an issue for smog police if they were to check warm-up characteristics, but in no way affects truck performance (I have been using a 180 degree thermostat in my Suburban for years for extended engine life. )



On grades at sustained 30 pounds of boost (Altamont 580 westbound at 65 MPH sustained) the truck heats up to 195 fairly quickly. As soon as the thermostat opens the temp visibly drops to 190 and never goes higher, even at sustained high power. I used to approach 220 degrees on this grade before under similar towing conditions.



After 2 months of mixed use I have not been able to get the truck over 195 degrees under any condition, ever. Admittedly it is winter and not hot out and I haven't been over any grades above 2000 feet yet, but I believe that the extra flow from the seven blade pump will prevent overheating in the summer because of the results I have seen so far. I also came over 17 from SJ to Santa Cruz today with most of the driving past Redwood Estates at 45 mph in second locked up at 32 pounds of boost. This grade is steady, curvey, and fairly steep. Before this would result in 220 degree coolant temps. Today I could not exceed 195 degrees.



If you run 250 to 350 hp you need to install the seven blade pump. It's a 30 minute job. I am sure the seven blade Cardone 5531412 will fit any truck from '89 up. They cost around $80. I am not a dealer and am not trying to sell or advocate any particular brand.



Jaybo

 

[JR]

Very nice write up thanks for sharing. I also run a 190 stat and there are times in the summer towing heavy I see around 210. Not overheating but definitely enough to make you pucker at times. What kind of weather do you see in the winter months? Im afraid living where I do it may be too much even with winter fronts on from Oct thru April I rarely see 190 unless Im hooked to something.

 

[jaybo]

Winter here is very mild never lower than freezing. On my trip to Sacramento last weekend I got up at 4 am for black friday and drove 40 miles to store. Tule fog out with temp about 45. Truck warmed up slightly slower than usual but reached 170 in ten minutes. I was anxious to get the heat on and while slower than normal it was fine. Don't know how it would do in zero degree weather but if you are restricting air flow I don't think you would notice much difference. You DO after all have a thermostat.

 

[Bob4x4]

Good luck with cardone parts of any type. They have not done well in any apps. I have seen yet. Not talking water pumps just the brand in general

 

[BigPapa]

I'm with Bob on this one. A1 Cardone is at the best mediocre.



Also, you may want to watch "upgrading" to a higher flow. A standard water pump will blow the freeze plug out of the back of the head if you run high RPM's. I've known people to clip the blades on a stock pump trying to cut down on the coolant flow for this reason. Most folks now running high RPM's run an electric water pump.

 

[jaybo]

Thanks for the opinions. I have used both OEM and Gates water pumps. The Cardone looks to be better quality but I have no experience with other Cardone parts. I have found however that you get what you pay for and the Cardone pump costs twice what a Gates pump costs. Incidentally I have also used Gates fan belts and found that they squeal all the time, no doubt because they cost less. If you can find a seven blade cast iron impeller pump use it no matter what brand.



As to the freeze plug issue, since the freeze plugs are the same on the 6. 7 and the 5. 9 block I would doubt that a water pump change would blow a freeze plug. In any case a water pump has such loose tolerances between the impeller and the block machined surface that the static pressure is inadequate to cause a freeze plug to blow even if the thermostat had no bleeder pin hole and was stuck closed. I would be more concerned about deteriorated components like the heater core or radiator. Remember, the maximum coolant system pressure is relieved by the radiator cap at about 15 psi.

 

[NIsaacs]

Remember, the maximum coolant system pressure is relieved by the radiator cap at about 15 psi.

Water pump/block pressure is not included in this figure. I would think that the larger the radiator the more flow you could stand. Too much flow in a small radiator might not allow the water to have time to cool. I did a check on O'Reilly's and they only show one water pump for all years. It appears to have 7 vanes with the ring connecting them.



Nick

 

[BDaugherty]

i think it's a great find. while the stock setup works fine for my use, those working further from stock parameters need parts that are further from stock. if i work on a truck with habitual overheating problems, i will add 7 blade water pump to my list of things to do/check.

 

[ILIANBG]

So, what is the difference between Gates water pump from Genos and an OEM or Cummins water pump. I am planing on replacing coolant, thermostat and water pump. Water pump is still the original one that came with the truck. Truck has a bit over 122k miles. What do you recommend?

 

[JR]

Are you having issues with your water pump? In most cases the pumps on these trucks will go trouble free for many miles. My former 00 had 340k on the original water pump when I sold it. For all I know it may still be on the truck. I realize not everyone wil last that long but if your not having any issues wirh yours at 120k I wouldnt have any concerns about leaving the original pump in.

 

[Bob4x4]

The older water pumps hold up much longer than any of the current offerings. I still have the oem on my 94

 

[ILIANBG]

The older water pumps hold up much longer than any of the current offerings. I still have the oem on my 94

Thanks Bob. I haven't talked to you in a while. I hope all is good.

It's good to know that. No, no issues with it. I thought it was something needed to be replaced at a certain mileage. I'm more then happy to leave it alone

 

[EDankievitch]

not sure what has changed but I had put well over 200,000 miles on the pumps that were in my 1989 but the pumps in my and my friends 04 and 05 trucks couldn't last past 75,000 -90,000. It didn't matter who's pump it was stock ( cummins) Gates or Cardone they all failed. Bearings failed first then took out the seal then the impeller.

 

[seafish]

I was also planning to replace the water pump on my 2005 (90k miles) when I flush the radiator this winter...

Given the shorter lifespan of the newer pumps, it just seems much more convenient to do everything at once, rather then having to drain partway when the pump actually fails. I might evne go ahead and replce the hoses with a Mr. Bobs silcone set, if the wife lets me.



All that being said, in the last 20 years of my life, I have found that rebuilding parts is often preferable to replacing with inferior parts... does anyone know if it is possible to source high quality bearings and seals for these water pumps and then simply rebuild them??

 

[AH64ID]

I know that 6. 7 owners are going to 5. 9 pumps when deleted because the 6. 7 pump is designed for the increased flow of the EGR cooler, without the cooler the 6. 7 pump moves the water too fast for efficient cooling. While this won't be an issue in the winter, I suspect it will be in the summer.

 

[Bob4x4]

not sure what has changed but I had put well over 200,000 miles on the pumps that were in my 1989 but the pumps in my and my friends 04 and 05 trucks couldn't last past 75,000 -90,000. It didn't matter who's pump it was stock ( cummins) Gates or Cardone they all failed. Bearings failed first then took out the seal then the impeller.

I would guess off shore bearings

 

[seafish]

I would guess off shore bearings

That's EXACTLY what I think... which is why I think that this pump, though inexpensive to simply replace, would benefit from a DIY rebuild with quality made bearings, if they can be found, which I think is highly likely, though I am NOT sure whether the seal might be available...

 

[Shamp]

I was doing other research and remembered this thread talking about blowing freeze plugs out from to much pressure with an upgraded pump. While it is for my 2004. 5 engine I dont think it would be much different.

 

[cerberusiam]

The freeze plugs blow out of the back of the head form excess heat around that cylinder flashing the coolant to steam, not from the water pump flow. #6 cylinder has restrictions to coolant that cause excessive heat retention under high power applications. They aren't blowing with stock power, mostly with hard throttle and ramped up fuel delivery.

 

[Wooter]

Going to buy a new water pump tomorrow and not a Cardone, Have had the overheating syndrome after replacing radiator, thermostat and supposed improved water pump !!!!!*&^%R