2001 F150 5.4L 170F coolant temperature

[ARB1977]

Hey fellas out of curiosity I hooked up my scanner to the 01 F150 5.4L with 115K. I wanted to see the coolant temp. At idle it reads 170 degrees. Have it a rev and it went down to 168. Granted its 60 degrees right now. We got the truck from my mother in law. It was my father in laws truck. He died 8 years ago. Knowing him he had a colder thermostat installed since he liked the engine to run cooler.

Is it worth installing the 190 factory stat since we down into the single digits some times in the winter. We live in north Texas. The truck was originated in California.

 

[demarpaint]

I would replace the thermostat with an OE part. You didn't say if you drove the truck or how long it was running. Having said that if you drove it a while then let it idle and it was 170F the thermostat is not allowing the engine to reach normal operating temperature which is a problem imo.

 

[ARB1977]

I would replace the thermostat with an OE part. You didn't say if you drove the truck or how long it was running. Having said that if you drove it a while then let it idle and it was 170F the thermostat is not allowing the engine to reach normal operating temperature which is a problem imo.

It was driven 8 miles. 55 mph on the service road. It’s my son’s truck who’s 16.

 

[demarpaint]

It was driven 8 miles. 55 mph on the service road. It’s my son’s truck who’s 16.

Change the thermostat to an OE opening at the temperature the engine called for. Running them cooler is not doing the engine or fuel economy any favors.

 

[CarlB]

Is it worth installing the 190 factory stat since we down into the single digits some times in the winter. We live in north Texas. The truck was originated in California.

Yes.

 

[Chris142]

If Ford had wanted it to run 170 they would have used that thermostat. I'm surprised that it has not thrown a p0128 code yet.

 

[SwampSurvivor]

You're definitely not doing it any favors running it with a low temp / no thermostat. They have oil coolers on them so I bet the oil never gets up to temp enough to burn off or evaporate off what it needs to.

My 01 5.4 with factory thermostat temp runs around 200 most of the time. I've hit 215 once but it was maintaining that no problem - that was with my foot planted towing a trailer up a steep will with the engine at 4000+ RPM.

 

[Lubener]

Is it worth installing the 190 factory stat

Yes. Regardless of where you live. An engine which runs too cool will have poor fuel economy, oil contamination and excessive wear. I would only use a Motorcraft thermostat which is rated at 190-195 degrees.

 

[JavierH19]

170 is probably a touch too cold and could cause a rich condition on some vehicles from what I know and that 180 is the minimum for computers to be happy. 160 is too cold for almost all ecu's. I changed the 195 in mine for a 180 and it's happy. I've checked with my scanner that it runs at 1 afr. Did that since it can get hot in traffic and it gives me a bit of extra headroom and instead of having it go to 230-35 it goes to 215-220 at worst. I haven't changed it in 5 years and have thought about changing it and the old looking hose recently. Maybe i'll experiment with a 170 and see what the air fuel ratio is. Can you check what your afr is. below 1 is rich and above 1 is lean but from what i know it's normal for them to bounce up and down a tiny bit but it can't be too far from 1 and for too long.

 

[emmett442]

If Ford had wanted it to run 170 they would have used that thermostat. I'm surprised that it has not thrown a p0128 code yet.

Pretty sure the strategy in a lot of these older Fords uses 140 as the "warm up" threshold.

 

[thastinger]

Hey fellas out of curiosity I hooked up my scanner to the 01 F150 5.4L with 115K. I wanted to see the coolant temp. At idle it reads 170 degrees. Have it a rev and it went down to 168. Granted its 60 degrees right now. We got the truck from my mother in law. It was my father in laws truck. He died 8 years ago. Knowing him he had a colder thermostat installed since he liked the engine to run cooler.

Is it worth installing the 190 factory stat since we down into the single digits some times in the winter. We live in north Texas. The truck was originated in California.

We have a couple of 10th gen 150s in the family, both with 5.4s
These came in a lot of different configurations as far as the cooling system goes. My 98 has a remote mount that puts the oil filter behind the front bumper, but my Son's has the filter on the block but has a water to oil cooler as part of the housing. Both of ours have transmission and oil coolers up front but my radiator is a 3 core and his is a 1 core...but they both take 192 T-stats.

 

[ARB1977]

Change the thermostat to an OE opening at the temperature the engine called for. Running them cooler is not doing the engine or fuel economy any favors.

I got one ordered.

 

[demarpaint]

I got one ordered.

Good move!