16 Ram 3 Way coolant Valve issues

[SitKneelBend]

Maybe? The pressure test should have found any leaks in heater core though. Not wet, doesn’t smell like antifreeze inside truck. Heat works.

Have you checked around areas that coolant goes to? I wonder if it can pass a pressure test with things like the 3-way coolant bypass in play because it seals off the leak area? IN other words, maybe the pressure test is isolated from the leak? Did they pressure test it under operation?

 

[Wild one]

Maybe? The pressure test should have found any leaks in heater core though. Not wet, doesn’t smell like antifreeze inside truck. Heat works.

What year and transmission does your truck have.If you have an 8 speed transmission,check the hoses and thermal management unit over that's on the side of the transmission,they feed coolant to the thermal management unit to help warm up the transmission. You might even want to check the transmission fluid to,as the thermal management unit has been known to develop an internal leak and then feed coolant into the transmission. The thermal management unit could have an internal fissure that only leaks when the trucks hot,and might pass a pressure test when the transmission is cold.Just a thought if you can't find any other coolant leaks

 

[akvanden]

What year and transmission does your truck have.If you have an 8 speed transmission,check the hoses and thermal management unit over that's on the side of the transmission,they feed coolant to the thermal management unit to help warm up the transmission. You might even want to check the transmission fluid to,as the thermal management unit has been known to develop an internal leak and then feed coolant into the transmission. The thermal management unit could have an internal fissure that only leaks when the trucks hot,and might pass a pressure test when the transmission is cold.Just a thought if you can't find any other coolant leaks

2018 w 8spd. I actually just changed the tranny fluid a week ago. It wasn’t overfull with coolant, if anything under. I drained 4 quarts and refilled with 5.5 once I leveled off the pan.

I may just have to take to dealership and see what they can find…..

 

[Wild one]

2018 w 8spd. I actually just changed the tranny fluid a week ago. It wasn’t overfull with coolant, if anything under. I drained 4 quarts and refilled with 5.5 once I leveled off the pan.

I may just have to take to dealership and see what they can find…..

If it's an 18 you'll also have the engine oil heater/cooler above the oil filter,it'd be another place to check over close,as they also have been known to leak coolant

 

[SitKneelBend]

2018 w 8spd. I actually just changed the tranny fluid a week ago. It wasn’t overfull with coolant, if anything under. I drained 4 quarts and refilled with 5.5 once I leveled off the pan.

I may just have to take to dealership and see what they can find…..

How did the fluid look?

 

[akvanden]

How did the fluid look?

If it's an 18 you'll also have the engine oil heater/cooler above the oil filter,it'd be another place to check over close,as they also have been known to leak coolant

Fluid was dark, 80k miles. Didn’t smell like coolant.

Replaced oil filter housing about a year ago with aluminum Dorman.

 

[SitKneelBend]

Fluid was dark, 80k miles. Didn’t smell like coolant.

Replaced oil filter housing about a year ago with aluminum Dorman.

It would would probably be noticeable too. I've seen what it looks like when the coolant gets contaminated and it tends to form orangish boogers in the coolant.