Simple question, I just can't seem to find the answer. Have a 2001 Grand Prix GT (no supercharger) with the 3.8L engine. Will be back-flushing the radiator and the flush kit says to tap into the heater core 'inlet' hose. There is an upper and lower heater hose off the engine about 6 inches apart that run to the firewall. Which is the inlet hose to the heater core? Thanks!

It dont matter.
disconnect both hoses and flush it out both ways!!
I was an ex mechanic.
Good luck!

yep and i am a tech

Thanks guys, but the reason I ask is I will be installing a permanent 'T' for connecting a garden hose. The kit says to install in the heater inlet hose. I just don't know which one that is.

Shoot a PM to R'Addiction aka John. He will know.

I had a 2000 GP GT, and loved it.

My experience is these plastic T fittings are a good source for a future leak. My advice would be to pull both hoses and just hold your garden hose nozzel up to the disconnected hose and push water both ways thru the heater core. You then can hold your hose against both fittings on the engine and do a pretty good job flushing out the engine. I have been doing it for years this way at the dealership.

Jerry.