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Coolant system fittings Issues - Attention all 1999-2008 GM owners............SERIOUS BUSINESS !

blue2002

Full Member
Joined
Sep 13, 2010
Messages
72
Location
Clinton IA
If you own a GM product model years 1999-2008, please read this whole story. It may very well get you off the side of the road and it SHOULD save you an imminent breakdown. It will DEFINITELY save you an engine if you'll make these repairs promptly.

This is just a friendly tip to those of you who own a 1999-2008 GM vehicle. I found a weak link in the cooling system yesterday in a most unrfotunate manner. I had been to a swap meet near Tulsa driving my '02 2500HD.  At about 80 MPH on a turnpike 60 miles from home I was alerted by the "check coolant temperature" light illuminating on the dash. I looked at the gauge just in time to see the needle blaze past the 230 mark on the way to the peg. I shut it off and coasted to the shoulder as steam rolled out of the front end. Great !  Here I am broke down on a turnpike with no buildings, people or resources in sight. I popped the hood to assess the situation.

I noticed immediately that the leak was high and above the back of the engine. The clue was the copious amount of steam and the coolant dripping from the hood. I'm smart like that.  It was then that I noticed a broken fitting going to the heater core outlet. Here's what the fitting looked like after the 5/8 hose fell off and dispensed the coolant back into the atmosphere.....


As you can imagine, I was really scratching my head at the mess I was in. Here I am standing on the side of the road with absolutely no means of getting the heater hose back on the outlet since the outlet nipple was broken off in the aforementioned hose. It was at this point that my mood shifted to anger at the pencil necked geek engineer who designed this type of connector in the first place. If I could have gotten my hands on him I would have beaten him to death with the offending hose connector. Fortunately I had a pair of channel lock pliers and a cooler full of water in the back of the truck.

I removed the clamp from the hose and the remains of the outlet nipple crumbled out in my hands. My initial thought was to disconnect the other water pump to heater core hose and just loop the hose back to the pump. That would work on our other cars right ? Not so simple on this deal. The other outlet is a 3/4 or bigger and while I was able to force the 5/8 hose on the water pump nipple ( It's amazing how pliable rubber is when it's blistering hot ), the 5/8 hose clamp wouldn't go over the nipple and the 3/4 clamp wouldn't tighten enough to hold it.  I managed to insert some plastic cut from a water bottle between the clamp and the hose and it held. It was at this point I realized that the puke tank/ reservoir was now useless as a coolant additive location since I had disconnected it from the system. The reservoir shares a hose with the other side of the heater core in the form of a "Y" type hose that I had just removed from the water pump. Refer back to previous engineer comments at this point.

Being somewhat of an "engineer" myself, I deduced that the only way to add coolant to the system now was to remove the upper radiator hose from the radiator, elevate the end of it to about head high and pour water into it allowing air to burp periodically. That technique worked like a charm and I was ready to go in no time. I was a bit concerned that this was now a sealed system with no vent capabilities but I figured I'd make a run for it anyway.  I nursed my old dog home the remaining 60 miles without a hitch and made the repairs today. In retrospect, these are my thoughts on the situation................

I love this truck ! It's the hardest working pickup I've ever parked my butt in and I show it no mercy. I've replaced a water pump, a fuel pump and a POS hose connector after 145,xxx miles of service. It spends more time with a trailer hooked than unhooked and I view the GVW warning sticker as just a helpful piece of advice that I ignore on a regular basis. A few weeks ago we made a long trip weighing in at just over 17,000 pounds combined.  :shock: It's a stud and I'll drive it till it drops !

I am darned lucky to have a cooler full of water in the bed of my truck. The ice had melted the day before and I hadn't refilled it yet. I try to keep an ice chest and drinks with me at all times during the summer months. Winter too for that matter

I was equally lucky to have a pair of channellocks laying in the back floorboard of the truck. I think I'll keep them in there from now on.

Keeping a couple of hose clamps in my junk box under the back seat is probably a good idea.

I'm also lucky the antifreeze ( ethylene glycol ) didn't light off on the exhaust and converter. It will burn and I have personally seen it cause a car fire.

I have researched this design and GM used these fittings on EVERY LIGHT TRUCK, VAN, SUV, MEDIUM DUTY AND HEAVY DUTY TRUCK BUILT FROM 1999-2008. They also used it on millions of cars from all of their brands. The odds are very good that you own one of these or a close relative does. REPLACE THIS FITTING NOW ! And do it every few years.

The factory GM part number is 15032062 and it will set you back about $33.00.  The Dorman number is 800-409 and will cost you about $7.00.

GM is not the only company to use this type of fitting. Check your ride and replace as necessary.

Preventive maintenance is the key. Save yourself some headache and change these every 50,000 miles or four years accordingly.

I have also concluded that not all engineers are pencil necked geeks. Kyle is an engineer ( for GM no less) but he's a long way from being a geek. For those engineers who are not pencil necked geeks ( all 5 of you ), I apologize if I have offended you.

I would still like to get my hands on the mental midget who designed this fitting. Why in the corn dog hell he thought he was improving on a system 100 years tried and proven is beyond me. Hopefully that sorry bastard was among the thousands of GM employees who lost their jobs in the last few years. If he was and if he's flipping burgers at McDonalds now........ EAT AT BURGER KING !  When I find him I'm kicking his ass !

Here's a few pics to help you make your own repairs. It was simple really and I used only the tools shown. It took me less than twenty minutes to reverse the band-aid engineering I had done on the side of the road and to replace the failed connector and fill the system with coolant.

Here's the tools you'll need...................................


Here's the GM fitting on the left ( made in Mexico ), the Dorman fitting in the center ( made in China ) and the Lisle connector release tool on the right ( made in the USA )


Here's the tool in place after the removal of the broken connector....................


Here's the new fitting pushed into place over the heater core outlet. I used a Dorman piece on my truck. The others are for my wifes Tahoe and my Dads Silverado...............


Here's a couple shots of the new GM part, Dorman part and broken part all side by side. As you can see, WHEN it breaks off you're screwed !....................................



Go get yourself the service part and save yourself some trouble. I don't think I hurt the engine since I got it shut off so quickly. BUT, I sure didn't do it any good.

Just a little friendly FYI, Dean
 
they used these POS's on grand prixs too.  Really ruins my day when the car is rendered useless due to a turd plastic fitting
 
Wait...So he's bitching about a simple part that fails after 145k miles of not-so-easy use (see 17k towing)?

It's also something he made work in 20 minutes using nothing more than channel locks and some ingenuity.

This is hardly "SERIOUS BUSINESS" in my book.
 
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Sorry To All About the Photos not working the first time
This Information Is from a friend on Bangshift.com and i thougth this may save some of you a breakdown on the side of the road
 
Yep plastic tends to get brittle and break with age and heat. Wait till that coolent jug let's go. 
 
Thanks for the information blue2002!Post like this helps everybody (y)
 
Well I just had a blast going through this same problem. Low coolant light has been coming on lately but the block never ran hot. After a pressure test I saw the leaking at that dreaded fitting. Looks like the rubber o ring was leaking. I read this post and decided to tackle it. Instead of buying the removal tool I used a chisel to delicately break the weak plastic off around the metal pipe. After visiting a few auto parts stores they were no help at all for this part. Even with the part number they had nothing for me. I decided to buy some small hose clamps and just pushed the hose over the metal pipe and tightened it down. So far so good.  I'll keep a good eye on it and hope it holds. 112,000 miles and this is the first fix I have really had to do. I still don't understand the use or purpose of this fitting at all. $2.50 for the hose clamps was a good fix.
 
This just happened to me.  I thought I was going to have to replace the heater core.  Thank goodness it was this plastic piece.  Took 20 min to change.
 
They are made like that so on the assembly line they just plug in the pre-assembled hose assembly, no tools, no having  to check and see if the clamp is tight. Just push it on, give a tug and if it doesn't com off it's go to go.

Don't go to the dealer for them most will charge $20 -$30 each.. Get them on line, ebay or GM parts web sites have them cheaper, usually under $5.00 ..


Connector Heater hose drivers side        PN-15032062

Connector Heater hose passenger side    PN 15151875






 
Randy said:
They are made like that so on the assembly line they just plug in the pre-assembled hose assembly, no tools, no having  to check and see if the clamp is tight. Just push it on, give a tug and if it doesn't com off it's go to go.

Don't go to the dealer for them most will charge $20 -$30 each.. Get them on line, ebay or GM parts web sites have them cheaper, usually under $5.00 ..


Connector Heater hose drivers side        PN-15032062

Connector Heater hose passenger side    PN 15151875

RockAuto shows the Dorman 800409 for both of those GM part numbers.
What's that about?

CarMech1969
 
Got the fittings today.
On my truck, I need two PN#15032062.
The PN#15151875 is the wrong size.
Anyhow, only one fitting was leaking (the one on the driver side), and it crumbled like wet cardboard as soon as I tried to remove it.
The other one is black like the new one I bought, so maybe someone changed it already?  ???
Imagine that thing letting go on the highway with the fishing boat in tow. I probably would have gone postal lol.
Thankfully, this problem was noticed in a timely manner by yours truly...as I did not see the leak, but could smell a coolant smell for the past couple of days. Now I can go fishing tomorrow  :B:

CarMech1969
 
Those are both the ones I put on mine. Wonder why the one didn't fit yours, I looked it up again and it shows another one (15059583) plus 15032062.. I think the one will fit both lines, the colors are probably just for the assembly line to connect the right hose to the right fitting.

They should be replace at every radiator flush or 100,000 miles. One of mine was leaking just enough to cause the system to slowly lose pressure and coolant over time without dripping or showing signs of leaking..
 
Randy said:
Those are both the ones I put on mine. Wonder why the one didn't fit yours, I looked it up again and it shows another one (15059583) plus 15032062.. I think the one will fit both lines, the colors are probably just for the assembly line to connect the right hose to the right fitting.

PN#15151875 crossed over as a Gates 28500, which is what I bought because the parts store only had one Dorman 800409 in stock, so I got one of each. lol  :D
The Gates 28500 fits a 5/8" pipe...and the Dorman 800409 fits a 3/4" pipe. Both of them fit a 5/8" hose. lol.
Looks like RockAuto has their listing wrong. If you search PN#15151875 on their site, a Gates 28500 pops up. Well guess what. They're wrong. It doesn't fit. So apparently, PN#15151875 is the same as a Dorman 800409 because if you search 'Dorman 800409' on their site, it shows that it replaces the two different GM part numbers you mentioned. Damn it! Lol. So that is how the confusion started.

Randy said:
They should be replace at every radiator flush or 100,000 miles.

Anyhow, the truck is fine for now, and like you say, it's wise to replace them periodically, so I'll be ordering a couple more of those to keep in the truck just in case of trouble. That being said, are there any other 'Achilles tendons' that I should be aware of in these cooling systems??
Thanks for replying to this issue.

Randy said:
One of mine was leaking just enough to cause the system to slowly lose pressure and coolant over time without dripping or showing signs of leaking..

Now that is a real bugger, a total disaster just waiting to happen! Glad you nipped it in the bud in a timely manner.

CarMech1969
 
I replaced mine with the hoses last year on my truck. A 2003 with 270k miles at the time. Those connectors were fine on my truck but I replaced them anyhow.

With the "new" heads and the hoses installed last year, currently been ~95F with 60+% humidity at 85 mph my temp is sitting at about 200F.

Transmission is about the same temp. Missing the AC but then again at 85mph and all windows rolled down, with occasional rear window removal, not missing the AC too much right now.
 
Well, as luck would have it....  :rolleyes:
The connector on the passenger side heater hose failed.
Alas - I have been here before....last summer....when I could only get one connector.
Stupid!
If I was able to buy two, I would have changed both of them at the time and been done with it.
Noooo....that's too simple.
We all know GM vehicles are extremely rare and exotic - so we'd better have only one connector in stock in case it doesn't sell!! :beating:
Anyhow
I noticed the leak when I was 4 hours out of town (could smell coolant), and of course, nobody around had one.
I had slipped over to the local breakfast joint, and returned to the motel with take-out.
Wifey and I had food, and by the time we were done with that, the engine was cool enough to get in there and mess around.
Heater hose broke away from the heater core with very little effort.
Tried to redneck a removal tool from a plastic bottle like before...didn't work  :E:
Breaking off the remains from the heater core pipe was a SOB, as there was no room to work, and caused me to use choice words.
Strangling that pencil necked geek who designed this stupid crap would be a contribution to society. Lol!
Anyway, in the end I just jammed the heater hose on to the heater core pipe directly, and clamped it off - which is the way it should have been in the first place. Oh wait...I know! Let's take ideas that have worked flawlessly for decades, and then throw them in the garbage  ???
Fixed is fixed - that's the way she'll stay!!

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CarMech1969
 
Ya know I wondered about that too, they work fine on the radiator.
 
I replaced both of mine this past spring.

I got both of the OEM hose and quick disconnect assemblies from the dealer parts department using my VIN to make sure I got the correct part.

I wasn't about to put aftermarket quick disconnects on there, after reading so many times that they broke again in short order.

It was a pain getting the old quick disconnects removed with the limited room to work in and the fact they had been there for who knows how long.

I'm pretty certain they were the original assemblies from the factory.

Having the correct quick disconnect removal tool helped a lot, but still.

But, I felt after 230K miles, I was pressing my luck and I had a couple of long trips scheduled in the coming months.

 
The funny part is that you don't even need those connectors.
One can simply push the heater hose onto the heater core pipe, and the problem is fixed.
When manufacturers come up with stupid ideas like this, and then they wonder why they lose customers when people get stuck on the road and have no way to repair it. The mindset of building vehicles to be simple and durable has been replaced with making them cheaply and quickly.....who cares what happens after the car leaves the line. Repairable? Not our problem.

CarMech1969
 
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