Heater Hose - Aluminum Parts Upgrade

[Yukon_driver]

Has anyone replaced the plastic hose connections on the firewall with metal aftermarket parts? Specifically the Dorman T connector and the Dorman 800-409 adapter? I attached pictures of these parts below for your reference. I have ordered these parts because I want to minimize the risk of failure in my coolant system, especially something that does fail so universally on these engines!

Anyway, I was hoping to get advice from someone who knows: should I expect to replace any O rings in this process? If so, can someone please provide me with a part number? I have had a pretty difficult time determing from the websites if I need new O rings and there is very little to find about them on youtube. Also, would anyone know the part number for the plastic clips that snap the adapters into place or will I need to transfer those from the old T connectors?

Thank you for your help!

 

[Tonyrodz]

Has anyone replaced the plastic hose connections on the firewall with metal aftermarket parts? Specifically the Dorman T connector and the Dorman 800-409 adapter? I attached pictures of these parts below for your reference. I have ordered these parts because I want to minimize the risk of failure in my coolant system, especially something that does fail so universally on these engines!

Anyway, I was hoping to get advice from someone who knows: should I expect to replace any O rings in this process? If so, can someone please provide me with a part number? I have had a pretty difficult time determing from the websites if I need new O rings and there is very little to find about them on youtube. Also, would anyone know the part number for the plastic clips that snap the adapters into place or will I need to transfer those from the old T connectors?

Thank you for your help!

View attachment 453901View attachment 453903

Pretty sure @89Suburban swapped his. He has a GMT900, but those are pretty much the same parts between the 2.

 

[Yukon_driver]

Pretty sure @89Suburban swapped his. He has a GMT900, but those are pretty much the same parts between the 2.

Nice thread man! Seems like you've done a lot of the things I want to do with my Yukon, I'll definitely be looking into your project for inspiration.

 

[Tonyrodz]

Nice thread man! Seems like you've done a lot of the things I want to do with my Yukon, I'll definitely be looking into your project for inspiration.

Thank you for the compliment. You're gonna have to weed out a lot of bs pertaining to my procrastinating lol.

 

[rockola1971]

Has anyone replaced the plastic hose connections on the firewall with metal aftermarket parts? Specifically the Dorman T connector and the Dorman 800-409 adapter? I attached pictures of these parts below for your reference. I have ordered these parts because I want to minimize the risk of failure in my coolant system, especially something that does fail so universally on these engines!

Anyway, I was hoping to get advice from someone who knows: should I expect to replace any O rings in this process? If so, can someone please provide me with a part number? I have had a pretty difficult time determing from the websites if I need new O rings and there is very little to find about them on youtube. Also, would anyone know the part number for the plastic clips that snap the adapters into place or will I need to transfer those from the old T connectors?

Thank you for your help!

View attachment 453901View attachment 453903

Lock clips and oring should already be installed on the new parts. Every replacement ive ever used has them installed. The top picture shows the clips installed. Cant tell on the bottom pic. You should be able to reuse your old locks if needed and assuming they are compatible with the new parts. Orings can be bought at just about any hardware store. They are nothing special since gas or oil is not involved.

 

[89Suburban]

Pretty sure @89Suburban swapped his. He has a GMT900, but those are pretty much the same parts between the 2.

Iamdub/Chris installed them and texted me the photos and info. I don't think he did that adaptor though. I have not seen that piece before in metal.

Links to the metal tee pics:

https://www.tahoeyukonforum.com/threads/the-what-you-up-to-thread.54016/page-7975#post-1947494

https://www.tahoeyukonforum.com/threads/the-what-you-up-to-thread.54016/page-7976

 

[Joseph Garcia]

Has anyone replaced the plastic hose connections on the firewall with metal aftermarket parts? Specifically the Dorman T connector and the Dorman 800-409 adapter? I attached pictures of these parts below for your reference. I have ordered these parts because I want to minimize the risk of failure in my coolant system, especially something that does fail so universally on these engines!

Anyway, I was hoping to get advice from someone who knows: should I expect to replace any O rings in this process? If so, can someone please provide me with a part number? I have had a pretty difficult time determing from the websites if I need new O rings and there is very little to find about them on youtube. Also, would anyone know the part number for the plastic clips that snap the adapters into place or will I need to transfer those from the old T connectors?

Thank you for your help!

View attachment 453901View attachment 453903

I would either use (1) OEM plastic Tees (Dorman plastic tees don't last as long), or (2) use the Gruven metal Tees.

When you change out the tees, be sure to wear gloves, as the firewall insulation is quite aggressive, and your hands will itch for days.

 

[Yukon_driver]

Iamdub/Chris installed them and texted me the photos and info. I don't think he did that adaptor though. I have not seen that piece before in metal.

Links to the metal tee pics:

https://www.tahoeyukonforum.com/threads/the-what-you-up-to-thread.54016/page-7975#post-1947494

https://www.tahoeyukonforum.com/threads/the-what-you-up-to-thread.54016/page-7976

I was not able to view the pictures, says I don't have permission or something like that. Could you drop the picture directly into the post maybe? It would be really cool to see the metal T's installed on someones system before I get started!

 

[Yukon_driver]

Lock clips and oring should already be installed on the new parts. Every replacement ive ever used has them installed. The top picture shows the clips installed. Cant tell on the bottom pic. You should be able to reuse your old locks if needed and assuming they are compatible with the new parts. Orings can be bought at just about any hardware store. They are nothing special since gas or oil is not involved.

Great, thanks! I just got the adapter from the second picture today and thankfully it does have the rubber seal on the inside and the clip is also pre-installed

 

[Fless]

I was not able to view the pictures, says I don't have permission or something like that. Could you drop the picture directly into the post maybe? It would be really cool to see the metal T's installed on someones system before I get started!

You should be able to view the pics now.

 

[bubbz22]

I replaced both today using the aluminum Dorman Ts. I didn't get the 800-409. Is that supposed to go on the end of the left T and then the hose with the spring clamp will fit it correctly? I just put the hose to the T and used a worm gear clamp. Seemed to do the job and I didn't see any leaks after about 15 minutes of running.

It did only take 2 gallons of coolant and seemed to be full. Does that seem right anyone that has done this repair after the plastic one failed?

 

[rdezs]

2 gallons after replacing the tee fittings sounds like a bit much, unless you replaced one or both of the hoses going down to the water pump? Then that would sound about right.

I always vacuum fill the cooling system, never have to worry about an air pocket.

 

[bubbz22]

The left side(black tee) broke while it was running and puked quite a bit of coolant out, probably should have mentioned that. It was started a total of 4 times before I did the replacement, each time for less than a minute. The last 2 times it didn't really lose any coolant, which is why I was figuring it would take more than 2 gallons.

I don't have the tools currently to vacuum fill, but they would be nice to have.

 

[89Suburban]

The left side(black tee) broke while it was running and puked quite a bit of coolant out, probably should have mentioned that. It was started a total of 4 times before I did the replacement, each time for less than a minute. The last 2 times it didn't really lose any coolant, which is why I was figuring it would take more than 2 gallons.

I don't have the tools currently to vacuum fill, but they would be nice to have.

When one of those tees let’s go it’s like slicing a jugular open.

 

[rdezs]

If you had one of those split, it's probably time to tackle the rear heater hoses behind the right rear wheel. Nobody really looks at them because they're pretty much out of sight. Just like the oil cooler lines, they're available from GM as a complete line set with the rubber section crimped on.... Alternatively, you can cut the crimps off and use the hose clamp of your choice and just replace the flexible hose. If you drop the spare tire, you have access to cut the original crimp off, or simply cut the metal pipe and use a compression fitting to convert to a hose barb in a more convenient spot. The 90° elbow off the bottom of the heater core..... It's a 3/4 quick disconnect x 5/8 hose barb.... I've only found them available by Dorman.

Above the spare tire

And behind the rear passenger tire

Those 90° fittings can be found here:

Dorman Heater Hose Connector https://a.co/d/a0fmrD0

And The originals removed at 170,000 miles

The hoses themselves and the original 90° fittings are exposed to whatever gets thrown up by the rear tire, as well as heat from the exhaust. So yeah, if you have a t connector on the firewall which is protected from road spray finally get brittle and break, you might want to pay attention to these ones as well.

If you go the route I did with a compression fitting on the original pipe, that pipe is 1/2 inch outside diameter.

After dropping the spare tire, here's what you're looking at. The two crimped hoses closest to the camera that look like they've been sleeping are the heater hoses. You can carefully cut the crimps off, and there's a hose barb under there. Or simply cut it off a little shorter and have more room to work with for future replacement.

This is all you need, in addition to 5/8 heater hose.... I used silicone heater hose for this.... And hose clamps of your choice. I prefer the oetiker clamps.

 

[89Suburban]

If you had one of those split, it's probably time to tackle the rear heater hoses behind the right rear wheel. Nobody really looks at them because they're pretty much out of sight. Just like the oil cooler lines, they're available from GM as a complete line set with the rubber section crimped on.... Alternatively, you can cut the crimps off and use the hose clamp of your choice and just replace the flexible hose. If you drop the spare tire, you have access to cut the original crimp off, or simply cut the metal pipe and use a compression fitting to convert to a hose barb in a more convenient spot. The 90° elbow off the bottom of the heater core..... It's a 3/4 quick disconnect x 5/8 hose barb.... I've only found them available by Dorman.

Above the spare tire
View attachment 459266
And behind the rear passenger tire
View attachment 459267

Those 90° fittings can be found here:

Dorman Heater Hose Connector https://a.co/d/a0fmrD0

And The originals removed at 170,000 miles
View attachment 459268

The hoses themselves and the original 90° fittings are exposed to whatever gets thrown up by the rear tire, as well as heat from the exhaust. So yeah, if you have a t connector on the firewall which is protected from road spray finally get brittle and break, you might want to pay attention to these ones as well.

If you go the route I did with a compression fitting on the original pipe, that pipe is 1/2 inch outside diameter.

After dropping the spare tire, here's what you're looking at. The two crimped hoses closest to the camera that look like they've been sleeping are the heater hoses. You can carefully cut the crimps off, and there's a hose barb under there. Or simply cut it off a little shorter and have more room to work with for future replacement.

View attachment 459269

View attachment 459270

View attachment 459271

View attachment 459272

This is all you need, in addition to 5/8 heater hose.... I used silicone heater hose for this.... And hose clamps of your choice. I prefer the oetiker clamps.

View attachment 459273

Good stuff. Saving this for later reference.

Tag: Rear Heat Tee Fitting

 

[Yukon_driver]

Alright guys, I've done it. Mostly. I replaced both of the plastic T connectors and respective adapters for the heater core hoses with aluminum counterparts for my 2002 GMC Yukon. I still haven't replaced the Y connector down by the water pump because I'm not prepared to drain coolant in my apartment parking lot.

Anyway, the aluminum parts work beautifully. Few thousand miles and no leaks. The only things you need are the parts, hose clamps, and some special line removal tools, I'll link them (you may also need new hoses if the plastic adapters have broken off inside/fused to hose). Follow any old tutorial on YouTube on how to replace them, the steps don't change whether you're using metal or plastic parts.

IMPORTANT: The Yukon/Tahoe models have different parts than Silverado/Sierra models. Maybe this is obvious to some of you, but the pickups don't have rear heater cores, and don't need the T connectors and they have different sized adapters that lock directly onto heater core pipes protruding from the firewall. SUVs need the T for the rear and the adapters are much smaller. I didn't know this, and apparently the techs at the auto store didn't know either. Lol.

ALSO: You will notice that the stock plastic T connectors are two different colors, whitish-yellow and black. I didn't think that mattered because they pretty much look identical, but I was wrong. You can still use them in place of each other, I discovered this because I needed to drive to work in the morning and refused to fail. However, it will be much more difficult to get one of them on if you order two of the same part number, as one part number is a 90 degree T and the other is a slightly more acute degree T. I just ordered two of the same ones by mistake and made it go together because it was 11:00pm. I believe the 90 degree one is meant to go on the passenger side, but I'm not sure.

I highly recommend getting the correct parts...pictures are linked to Amazon.

Dorman Part Numbers: 800-413HP; 800-414HP



The adapters are both the same: 800-403HP

This is all plug and play guys, just use a little lubricant on the seals (pre-installed at factory) and put it together. These little guys are going to last forever, I know it. At least 100K miles if not more. Trust me, you want the line disconnector tools!!! Please just do this for yourself, I beg you. They are linked below:

Amazon.com

I hope that this post finds someone like me who really could have benefited from it, please share! Here are some photos of mine:

Thanks to anyone who followed my story, sorry for the length.

 

[Yukon_driver]

If you had one of those split, it's probably time to tackle the rear heater hoses behind the right rear wheel. Nobody really looks at them because they're pretty much out of sight. Just like the oil cooler lines, they're available from GM as a complete line set with the rubber section crimped on.... Alternatively, you can cut the crimps off and use the hose clamp of your choice and just replace the flexible hose. If you drop the spare tire, you have access to cut the original crimp off, or simply cut the metal pipe and use a compression fitting to convert to a hose barb in a more convenient spot. The 90° elbow off the bottom of the heater core..... It's a 3/4 quick disconnect x 5/8 hose barb.... I've only found them available by Dorman.

Above the spare tire
View attachment 459266
And behind the rear passenger tire
View attachment 459267

Those 90° fittings can be found here:

Dorman Heater Hose Connector https://a.co/d/a0fmrD0

And The originals removed at 170,000 miles
View attachment 459268

The hoses themselves and the original 90° fittings are exposed to whatever gets thrown up by the rear tire, as well as heat from the exhaust. So yeah, if you have a t connector on the firewall which is protected from road spray finally get brittle and break, you might want to pay attention to these ones as well.

If you go the route I did with a compression fitting on the original pipe, that pipe is 1/2 inch outside diameter.

After dropping the spare tire, here's what you're looking at. The two crimped hoses closest to the camera that look like they've been sleeping are the heater hoses. You can carefully cut the crimps off, and there's a hose barb under there. Or simply cut it off a little shorter and have more room to work with for future replacement.

View attachment 459269

View attachment 459270

View attachment 459271

View attachment 459272

This is all you need, in addition to 5/8 heater hose.... I used silicone heater hose for this.... And hose clamps of your choice. I prefer the oetiker clamps.

View attachment 459273

Thank you for this, very helpful.

 

[DRLexpress]

So just to be clear, I need to order one each of the tee's and 2 of the connectors?

 

[bubbz22]

So just to be clear, I need to order one each of the tee's and 2 of the connectors?

If your factory quick connectors are in working condition, you don't NEED the 2 connectors. I had one of the quick connectors that seemingly had broken in the past(before I got it) as it wasn't there and had a spring clamp on the hose. On that side I used the 800-403hp connector, and had to switch to a worm gear clamp as the spring clamp would leak after the vehicle was off for about an hour. The other quick connector was still intact so I didn't use the 800-403hp connector on that one, just clipped it onto the T-fitting.