Heater hose size 2002 Regal

[rodinaz]

Yes I know it seems simple enough but I never had time to take off the hoses. I went to AutoZone to order them. I thought both was 1/2" inside. However AZ looked up the heater core and it shows one end to be 5/8". So they are saying one hose is 5/8 and one is 1/2. They look the same size to me is the reason I'm checking here.

Thanks, Rod

[BNaylor]

They look the same to me too on both my '99 LS and '01 GS Regals. 5/8" is pretty standard for GM heater hoses.

[rodinaz]

I went ahead and took off both hoses at one end, they both are 5/8", thanks for your help.

Rod

[BNaylor]

Thanks for the feedback. Good to know. I sure hope it is 5/8". Reason why is I checked the fittings I used for the flush tee connector in one of the Regals and the one I have installed is the 3/4" tee. I believe the 5/8" tee was too small. The Prestone Kit came with 1/2", 5/8" and 3/4" tees with the clamps. The 5/8" did not fit right for some reason. Maybe it was changed in the 2002 year.

[rodinaz]

I have an addition. Since my last post I bought both hoses from the dealer. The local auto parts stores just did not have them pictured correctly.

The hoses are 5/8" at the engine but the lower is 3/4" at the heater core . The upper is 5/8" at both ends. At the heater core end they are labeled, on the hose, LWR core and UPR core. GM inlet/lower #10427568 and outlet/upper #10427571. The lower at the core is the upper on the engine and upper core is lower on the engine. Hope this helps others.

Rod

[BNaylor]

Thanks for the update. Yeah I found out the same when I recently replaced the heater core in our '99 LS. The bottom port (pressure) at the heater core is definitely bigger at 3/4" versus the top (return) which is 5/8". See pics.






Delphi Heater Core HC0379