Three Way Coolant Valve Bypassed??

[Jwrigh12]

Hi Everyone!

I've been lurking on these forums for quite some time, hoping to one day the ranks of RAM owners! Well, a couple weeks ago, I was finally able to pick up a 2014 RAM 1500 Lonestar with a 5.7 Hemi. Everything seems to be in solid shape! The only issue I had (and noticed before I purchased it) was that the lower radiator hose needed replacing. The previous shop had incorrectly installed the hose clamp, and it had a pinhole leak.

Decided to do the work myself and save a bunch of money! While I was in there, I came across what looked like a pump of some sort, plugged into the wiring harness, but nothing connected to the hose barbs/ports.

After some investigating and digging, I found that this is the Three Way Coolant Valve. Upon even further inspection, it appears that the hoses that should be connected to the valve barbs have been attached to a simple hose Tee fitting...essentially in an all ports always open configuration.

My best (uneducated) guess, is that the valve body cracked, the the valve was operational. So the previous owner, in an effort to save money, rigged it this way. valve is plugged in to avoid a CEL code, and the hoses were connected to the tee to fix any leak.


So, Im calling on the collective wisdom here to help see anything I might have missed:

1. Thoughts on my initial diagnosis?
2. Is this a valid fix? (AKA, should I spend the money and replace the valve, or leave it as is?)
3. What might be some symptoms of this modification?


From my understanding, this system is a transmission heater of sorts, correct? Ive noticed that the trans temp is a little warmer than most people say. Nothing concerning, but on a recent drive through the mountains i was in the high 180's - 190's. Could this be because the coolant is constantly "warming" the transmission, even after not needed?

Thanks for any help in advance!

 

[Wild one]

Hi Everyone!

I've been lurking on these forums for quite some time, hoping to one day the ranks of RAM owners! Well, a couple weeks ago, I was finally able to pick up a 2014 RAM 1500 Lonestar with a 5.7 Hemi. Everything seems to be in solid shape! The only issue I had (and noticed before I purchased it) was that the lower radiator hose needed replacing. The previous shop had incorrectly installed the hose clamp, and it had a pinhole leak.

Decided to do the work myself and save a bunch of money! While I was in there, I came across what looked like a pump of some sort, plugged into the wiring harness, but nothing connected to the hose barbs/ports.

After some investigating and digging, I found that this is the Three Way Coolant Valve. Upon even further inspection, it appears that the hoses that should be connected to the valve barbs have been attached to a simple hose Tee fitting...essentially in an all ports always open configuration.

My best (uneducated) guess, is that the valve body cracked, the the valve was operational. So the previous owner, in an effort to save money, rigged it this way. valve is plugged in to avoid a CEL code, and the hoses were connected to the tee to fix any leak.


So, Im calling on the collective wisdom here to help see anything I might have missed:

1. Thoughts on my initial diagnosis?
2. Is this a valid fix? (AKA, should I spend the money and replace the valve, or leave it as is?)
3. What might be some symptoms of this modification?


From my understanding, this system is a transmission heater of sorts, correct? Ive noticed that the trans temp is a little warmer than most people say. Nothing concerning, but on a recent drive through the mountains i was in the high 180's - 190's. Could this be because the coolant is constantly "warming" the transmission, even after not needed?

Thanks for any help in advance!

If you wanted to clean things up under the hood,you can buy the heater hoses for a 2013 6 speed truck,and go back to the older style hose set-up that only feeds coolant to the heater core(heater output seems better with the older set-up in my 14).This works good with one of Caulk04's bypasses to drop your transmissions temperature.Look for posts by Caulk04 in the search bar,and you should find Jesse's simple bypass that gets rid of the 8 speed transmissions thermostat,which has been known to fail occasionally

 

[Jwrigh12]

Ok, So lots of reading ahead. But from what I gather so far, it seems that the baseline step forward (before I get crazy with lots of swap mods) would be to replace the three way valve so Im not constantly sending heated coolant back to the transmission, and look into Caulk04's thermostat bypass.

I checked the trans temp on some driving I did today and I was incorrect. After a 25 min highway drive at about 75mph, I was sitting about 190-195 trans temp. Outside temp was 22 degrees. Then I took some off road trails for a couple hours and the transmission stayed in that temperature range.

 

[Jwrigh12]

Im also looking for any info on this apparent valve bypass situation I have going on here. Would replacing the valve with an open tee cause any major issues, or induce problems? Trying to find out if this is an issue I need to jump on immediately, or if I can focus on other things for the moment? Thanks again for the help!

 

[crazykid1994]

Actually 190° is normal with the factory heater assembly. My trans temps were always at 192°. I have a 2017 so they actually updated the coolant lines. My lower radiator hose has a tee in it with two 1/2” barbed fittings. One went to the transmission heater and the other is the heater core in the dash. No valve to adjust flow to the trans. As far as I know when the engine gets to full operating temp the valve is no longer functional and stays in the middle so full flow to both sides

 

[Jwrigh12]

Got it. So... assuming my original assumption (valve body bad/leaking, but actuator functioning) leaving it set like it is isn't a horrible idea? Full flow to both, and no CEL because the actuator is working. Next step would be the thermostat bypass to bring down temps. Any objections to that thought process?

 

[crash68]

Im also looking for any info on this apparent valve bypass situation I have going on here.

That three-way valve is it to divert coolant to the transmission TMU when not needed by the cabin for heating. The TMU has it's own thermal bypass to control the fluid temperature. As for the transmission temperature, unless the fluid is spiking considerably higher than the coolant temperature it's fine. The fluid and the materials in the transmission will handle the "high temperatures" most on the forum whine about.

 

[crazykid1994]

Crash68 is correct. Most manufacturers that use the zf trans actually run them around 200°. BMW is one of them. The dodge cars do not use a heater. They use an inline thermostat and take forever to reach operating temp. I bypassed the heater on my truck but have plans in the future to install an inline thermostat at 145° to help keep temps up and faster warm up.

 

[tcp2133]

My check engine light is on. I ram the coffee and the three way valve is the problem.I ordered one from eBay and the port marked ALT is plugged. It’s hard material not like rubber or plastic. Any info or had intone send this problem?