I just replaced all 8 coolant hoses and 2 serpentine belts. I found some part numbers were difficult to find so I thought I would share this information. I used 7 Gates hoses and 1 GM hose. Three of the Gates were not a perfect fit and I will describe what I had to do.

Gates 22405 lower radiator hose, perfect fit, I reused original spring clamps.

Gates 22404 upper radiator hose, perfect fit, I reused original spring clamps.

Gates 18125 90* elbow hose from throttle body to coolant pipe. This hose is shorter on both ends and has a smaller o.d. I replaced both spring clamps with with worm clamps. I also bought a 1/4” brass barb and did the throttle body bypass mod. The mod allowed me to push the short ended hose onto the coolant pipe far enough to get a good seal. The other end of the hose goes onto the barb. There’s a lot of debate whether this mod is worth the effort. Since I already had the shorter hose the mod was a good solution.

Gates 19816 surge tank outlet to water pump hose. The surge tank end had an extra bend about 2” long. I cut that off and it worked. I reused both original spring clamps.

Gates 18127 radiator to throttle body hose. The radiator end is no problem and I reused the original spring clamp. The throttle body end has a smaller o.d. than the original hose. I replaced that spring clamp with a worm clamp. In my case, this is the end that I connected to the 1/4” brass barb for the throttle body bypass mod.

Gates 18447 heater core pipe to water pump hose, perfect fit, I reused both original spring clamps.

Gates 28417 heater core pipe to surge tank hose. This is a 5/8” straight hose. It actually measured 9/16” I.D. There was a lot of discussions about the original hose being metric with an obsolete part number. This hose fit perfectly and I reused the original spring clamps. I bought the minimum 6’ from Rock Auto and the packing slip showed a different part number 28491. I assumed this was because there is 6’.

GM 10408463 superseded by 10229488 surge tank inlet to radiator hose. This hose makes a 180* turn. The only option from Gates was a straight hose #28409. I imagine that you could bend it enough to make it work but I did not like that option so I bought the OEM hose. This hose was by far the most expensive one. It alone cost almost as much as all the other Gates hoses.

I also bought a new Gates surge tank cap. The new ones are 18 p.s.i.
The part number is 31544.

Gates K060798 main serpentine belt.
Gates K040420 air conditioning belt.

I also bought some special tools from Amazon that I highly recommend.
Lisle 17100 flat band hose clamp pliers.
Astro 9502 hose removal hook set.
Astro 9409A hose clamp cable type pliers.

One more tip...I removed the battery and it’s plastic surround. It made it so easy to get to the heater core hoses and clamps.

It’s also best to do the belts after you are done with the hoses. Spilling coolant on the belts will make them squeak.

Afterwards I took the car in to a local shop and had a power flush done. I did not let them add any chemical flush cleaners, just suck out the old and put in fresh coolant. In the past I had bad experiences with my radiator and the heater core tank seals leaking.

My goal was to single source the belts and hoses to save on shipping costs. I was successful except for the one GM hose. The tools were Amazon Prime so the shipping was free.

I hope this helps some of you in the future.

Leave the Gates 18127 throttle body hose disconnected at the throttle body end until you refill the surge tank. This allows the air to escape.

When I drained my old coolant I used a clean drain pan. I refilled my surge tank with the old coolant because I knew it was going to be flushed out the next day. This was my way of getting rid of the old coolant in an environmentally safe way.

 

Great info, thanks for sharing!

 

Thanks, also. I'm about to replace my hoses, as well.

Spaggs

 

Thank you!!

 

 

Excellent info and a great job!
I just discovered yesterday that my 04 has the original hoses from late 2003 still installed. Going to use your info to change hoses. I am thinking I should change the thermostat at the same time.
Did you consider changing the thermostat while the system was down?

 

I did not change the thermostat. My car only has 50,000 miles on it. It would be easy to change the thermostat during this process. It’s probably a good idea to do it also. Good luck with the project!

 

Thanks.
My car has 56,000 miles on it. According to service records, the cooling system was flushed and refilled in 2008 at a Chevy dealer. No mention of a T-stat change and definitely no hose changes.

 

I found this at rockauto: Dayco 86500, it has a center length of 8.25" The Gates 18125 hose has a center length of 4.2". If the Gates hose is too short on both ends, then the Dayco is probably a better fit:

https://www.rockauto.com/en/moreinfo.php?pk=960880&jsn=7574

I also found Dayco 88413 (rockauto shows it as matching GM 10229491), might be a better fit than the Gates 19816 hose (doesn't match the GM part number):

https://www.rockauto.com/en/moreinfo.php?pk=961153&jsn=8328

 

I believe the model number should be Gates K060802:

https://www.rockauto.com/en/moreinfo...423921&jsn=444

 

This is the wrong part number for the hose which goes from the surge tank outlet (the forward facing nipple) to the water pump. If you have to cut it to make it fit, it ain't the right one, not to mention possible stress on the hose if it bends in ways for which it wasn't designed. (I believe that Gates part # is for certain 4cyl GM engines.)

The correct part # is GM 10229488. Amazingly enough, I found it at my local GM dealer - they had to order it. Fits perfectly. No cutting.