2002 Chevy Venture headache

I have been having problems for about 1 1/2 months. My dash gauge never indicates it is overheating. Within this time both heater hose tee’s have broken. One of the new ones only lasted about 2 weeks before it broke on all 3 connections. Now the heater hose connector broke. Does anyone know what could be causing this?

I’ll be willing to bet they are all plastic. Seems they become suspect after 10-12 years of service. Even with proper maintenance done.

The car is old enough (over 10 years) where items that are affected by ground level ozone are going to start failing including plastic and rubber items.

I don’t envy you at all. I have had to do those heater hoses before and doing anything in the space back there is inhuman.

I only see one report of a new tee. How many of the new ones have broken, and what has been the sequence - you must have worked on it multiple times by now. Each time everything would have taken abuse and those things are surprisingly wimpy. A lot of aftermarket parts are terrible too.

Anytime cooling system things keep blowing I start to wonder about a head breach allowing exhaust gases into the cooling jackets and building pressure. This can happen without any other signs of a head problem. I doubt this would be your failure mode, its just a thought.

Yes they are all plastic. One new plastic tee broke at all 3 connection points. I was thinking that the added stress from my fat hands in that tiny space may have attributed to the others breaking, but the new one is weird.

I replaced one heater hose(that was broke) and the thermostat just for the heck of it. I gave it the boil test and it did open. Could it be air in the system?

Air in the system would put less pressure on the connections if anything. There could be air in the system, but as long as the engine isn’t overheating due to the air, that wouldn’t cause these plastic component failures. What I’d do if it were my car is just bite the bullet and replace all the plastic cooling system connectors at this point with new ones. I expect this is caused by the selection of the wrong type of material or inadequate dimensions at the time the car was designed. Car manufacturers are always trying to save space, parts expense, and weight, and I think you are suffering from this frugal-ness now.

Air in the system would almost defiantly make the engine run hot. Have you replaced the temperature sending unit?

Have you checked for worn or loose engine mounts? One or more bad mount can cause the engine to rock during normal driving, pulling on the heater hoses one way or another.

All of the above mentioned things can cause the plastic tees to fail, but I’m willing to bet that they are just cheap plastic junk and don’t need any external forces to make them fail as they age. This is an Achilles heel of GM vehicles of this period, no doubt to save $1.49/vehicle. If you can find replacement metal parts I would replace all the tees with metal ones.