Low temperature 6.4 thermostats

[Mike_D]

Anybody running a set of the Mishimoto low temp thermostats in their 6.4? If so, what kind of ECT temps are you seeing during 90-100 degree ambient days?

I am thinking about ordering a set to drop in before the heat hits. This is my first summer with the 6.4 and I am already seeing temps around 200* ECT just cruising unloaded. Coming from my 6.0 and Duramax days, I am so used to 190* solid.. Just seems pretty warm being empty.

Thanks for the input

 

[capt dong]

Got a set. Waiting to put them in.

 

[Mike_D]

I just ordered a set on Amazon, should be here Friday for a weekend install. Hoping to keeps temps under 200 while unloaded.

I know these newer engines like heat, but the 190* area seems warm enough from what I understand.

 

[Martin #6]

Sub'd.

 

[Mike_D]

Got them in last night. Awesome quality in comparison to the motorcraft stats I had in there.

As for temps-
Idle fully warmed up is 188
Cruising on the highway is 190-192
Decent hard throttle getting on the freeway is 196 and drops right down
These are with 102* ambient temps.

Will report back with towing temps when I get a load hooked. But so far, I'm thrilled with the new coolant temps!

 

[capt dong]

What tune are you running mike?

 

[08twinturbo]

Guys they work awesome. Just did some in a customers. You should see 190ish. That's where his sits all the time now. He was impressed.

 

[Mike_D]

Fully updated mini max on the street tune. 100% deeelllleeettteedd

 

[Strokethis04]

Anyone got a link to them?


Sent from my iPhone using Tapatalk

 

[Wizbangdoodle]

I rebuilt my motor last summer and just put stock thermostats in at the time. I see 192-194* all day long. That being said, I don't have the ambient temps you have. The best I can compare to is about 90*. I'm thinking you have other issues if it runs 200*+ empty.

 

[Mike_D]

I would think that if I had other issues, I would still see high temps with the new mishimoto thermostats.

The motorcrafts I pulled out had 197* and 205* on them.. Thinking that explains my 200* unloaded.

 

[08twinturbo]

Here is the link. They work nicely.
http://m.mishimoto.com/ford-6-4l-powerstroke-low-temperature-thermostat-08-10.html#0

 

[dohcter]

Are your oil temps lower as well?

 

[08twinturbo]

188 coolant temps and 194 oil is highest I've seen even pulling a boat. In city. Unhooked it drops way down to like 170 coolant.

 

[capt dong]

195-197 ect and deltas of 4-10 on the eot prior to my leveling kit cruising at 2k rpm. After the level its 199 ect with 8-12 degree deltas. My system is healthy because the temps come way down at lower rpm or idle. I just want to run a little cooler cruising at higher rpm. Hopefully get around to it in the near future.

 

[Mattyh3]

Anyone have issues with mishimoto low temp thermostats in there 6.4? This is the 2nd set of thermostats I’ve gotten from them and both have been stuck open out of the box. I can’t get the truck over 170 degrees even on the highway, and idle it drops down to 150s. Outside temps are 80 degrees. P0128 code as well so I’m confident they’re stuck open. Is there something that I’m doing wrong when installing these? They want me to purchase a replacement set at a “discounted” rate because I waited a few years before putting in the replacement set they sent me originally since I had already put in a new set of OE temp ones before they got to me. A little hesitant to buy a 3rd set

 

[webb06]

Anyone have issues with mishimoto low temp thermostats in there 6.4? This is the 2nd set of thermostats I’ve gotten from them and both have been stuck open out of the box. I can’t get the truck over 170 degrees even on the highway, and idle it drops down to 150s. Outside temps are 80 degrees. P0128 code as well so I’m confident they’re stuck open. Is there something that I’m doing wrong when installing these? They want me to purchase a replacement set at a “discounted” rate because I waited a few years before putting in the replacement set they sent me originally since I had already put in a new set of OE temp ones before they got to me. A little hesitant to buy a 3rd set

You might make sure the thermostat ear didn’t slip out of the lip indention on the housing. I recently installed a set and actually had to bend the ears out a little so that it didn’t slip off the housing. If they do slip off it’ll act just like a thermostat is hung open.