Water pumps and fan clutches!

[Playsinsnow]

Hi everyone, had some questions that are still bugging me after searching the OS and anywhere else for some time now so I finally registered here.
Whats the difference in performance and function of a cast iron or steel impeller water pump? Flow and weight? AC Delco has one of each avail-leaning towards one labeled oe yet rock auto has a cute little heart next to the cheap cast iron one ($#*% whens valentines-whew).
Fan Clutches, Hayden and Dorman seem to be the most prominent brands (want a behr but the local stores don't have em). Any preference over the other? I want it to act oem and Ive read old posts of bad Dorman connectors. Should I use the original connector or is everything good now?
And what's this nonsense on a flash? Ive got an '05 (11/04 DOB) TB LT 4X with 111,5xx. Do I need to go to the blasted stealership for a flash or you think a shop could do this? Black electrical tape was great on the 200k miles I put on my mazda in college but not now.
Water Pumps shaking a little and my "whoosh" has gone away for now. Whine has gotten louder though and its definitely coming from front and center. I'm hoping to hear from some of you that unfortunately had to do these repairs years ago ( got mine 05/07 with 17k) and if you have had to replace the replacement. Thanks in advance and to all those who got this and the OS up. (I found this site after seeing No Longer With Us on Roadies ID-whew)
RockAuto or anywhere else had discount codes? Thanks!


I'll fill out my profile soon, promise. again its an 05 TB LT 4X stock with K&N drop in. 111k with tires currently at treadbars frown: always something putting the LTX's off)

 

[The_Roadie]

Welcome! Glad you discovered I wasn't dead.

I've never changed my water pump, so I don't have any opinion on the impeller issue. Odd that it's never been discussed.

I use a Hayden fan clutch. Been fine. The Dormans did indeed have problems, even though I tried to get somebody with a failed one to send it to my Dorman contact for a deeper failure analysis.

Independent mechanics exist with GM Tech II tools and the means to download a new flash to your PCM to improve the fan clutch operation, but it's not a mandatory item. It helps the longevity a bit due to reducing the amount of solenoid valve activity, and spins the fan up more on a start on a HOT day, when the engine doesn't need cooling but the AC condenser that cools the cabin does. Call around, Google for them, and check their Yelp reviews.

 

[Playsinsnow]

Thanks, Hayden it will be. FWIW I replaced just the water pump (and the idler pulley for 2nd time in ownership bc it did not spin smoothly with the belt off.) Buddy has an '07 envoy and wanted to do it today so he knew how to remove his fan shroud. Got a duralst cast iron pump, I'd say a lot more than just "some" coolant spills, and any wiggle in the fan is gone (1/4" previously) Didn't realize how much of the motor I wasn't hearing. I figure for a $25 pump I will replace it when again if nec when fan clutch decides to go supercharger on me.
And until I hear otherwise I will assume that a cast iron water pump is a cheap molded heavy piece and a stamped steel impelled pump is for those that want to pay for it and feel like they are getting something in return. TBSS, prob would the

 

[tblazerdude]

Looking at buying a Hayden Fan Clutch off rockauto, as my truck needs one before summer. Roadie and playsinsnow, are you still satisfied with your purchases? Hayden is $158.99, AC delco is $236.79. I tend to use OEM parts but that price is slightly scary.

 

[Playsinsnow]

Yes, it did the trick. Only thing I'd do different is maybe take a few extra mins to rinse ALL the coolant off that spills. I was checking for leaks obsessively for the next couple of weeks bc I could smell coolant everytime I parked inside. I don't think I've heard anything against the Hayden. Plus the Roadie uses it and hasn't advised others against it! You'll be pleased that it runs smoother than the parts that are on now.

 

[AV8ER]

just replaced my fan clutch the weekend before last and if i recal it was in a hayden box but there was a behr fan clutch inside. I got mine at o'reilly auto parts for 199+tax. So far so good! After reading this i'm curious what the differences between a hayden and behr are other than brand? Another thing about the change that i found weird was the fact that when i put in the new one it stayed locked up for a few miles until I pulled out on the highway and stepped on the gas pretty good.

 

[Playsinsnow]

My understanding is that a newer fan clutch kicks in after it reaches a warmup temp. Also, from what I've read (a lot) behr/hayden seems to be a very safe bet to save a few bucks over AC Delco. Others bought a Hayden with a Behr inside. Maybe someone else can elaborate on this. I'd feel comfortable with either. I believe they are both built to the same "specs" and are virtually identical.

 

[Mypetropig]

Just noticed that I have a growling sound coming from my fan clutch . As I understand it Hayden is the part off choice. As for the water pumps,I see that some have a cast iron impeller and others do not. Need a good pump but cant spend an arm and leg. Has anyone used a Bosch pump or something other than Delco with good results. I don't want to do this again anytime soon.

 

[Playsinsnow]

I bought the cheapest water pump (duralast? I think) and all is good 6+mo.s later. 30some bucks I believe. Figured any new pump with a new pulley/shaft/blade will function better than the loose/worn pump its replacing. I asked about functional differences/benefits of cast iron vs steel impeller water pumps on here a while ago and no one tried to convince me to spend more $$ on a specific water pump. also, Hayden fan clutch all the way.

 

[Mypetropig]

I did some research and found out that most use Ni-Resist cast iron for pump impellers. This is a high Ni cast iron that has very good corrosion resistance and fair wear resistance.Fabricated impellers are usually difficult. Even if manufactures can get the geometry correct they tend to have issues with fatigue at welds over time. That being said I don't think its the geometry or the welds, its that big bulky fan clutch that's attached to it. No matter what I still have to replace it. Cant come at a worse time though, I am in the middle of remodeling our kitchen. At the end of the day I have 112k on the original fan clutch but only 44k on this water pump. I was planning on doing a slightly overdue coolant flush and this will be a hell of a way to get it all out. While I have it torn apart I am going to install new hoses as well as the t-stat and coolant sensor that's been sitting in my garage for some time now.

 

[Mooseman]

I installed a Gates when I swapped the engine in July 2011, so far, so good. Can't remember if it was a cast iron impeller or stamped.

 

[Mypetropig]

While continuing my research I have seen threads where folks say to use the 05+ model fan clutch. These are older threads so I was wondering if this is still the case. I have noticed different part numbers and pricing on the 05/06 model years. One would think that by now all of this mess has been straightened. When I had my tune installed a few years back they uploaded the most recent software at that time, which to my understanding had the newer fan clutch info. Any insight on this would be helpful as I need to order my parts soon.

Thanks

 

[Playsinsnow]

My understanding is that applies to oem replacement. Behr/Hayden clutches are updated- sorry haven't considered others.

 

[Mypetropig]

That's good to know. I was going with the Behr/Hayden clutch since that seems to be the better choice, just needed that cleared up. Its odd to me that the others have different pricing if they are all the same but I guess we cant solve all of life's little mysteries. Thanks for your thoughts on the matter.