The price a man will pay for comfort!!

 

Comfort wasn't my main concern. I drove a 1978 VW Bus as my daily driver even in the -30deg. Talk about no heat. I only used my truck when I was going on a longer trip or on my leave time. I was more worried about the truck temp running at 130deg. that was all the warmer it was getting.

 

Just called the local dealership parts department. They ran my vin and said that the stock stat for my truck is a 180 (they have a policy of not giving parts numbers over the phone). According to him, there is only one stat listed for my year.

Rock Auto shows motorcraft part# rt1195 as a 190, also lists other brands as oe type, and in 180 and 195.

Something isn't adding up here for me. I am 100% going to replace the one I have, but I want to make sure I put the best temp one in there. Priority to stock / better mpg than performance.

Any ford parts guys or techs that lend some insight to the discrepancies? Wondering if the ecm will accept different temp stats or will there be problems. I'll go to a 195 if the computer will accept it.

 

Well, I looked it up at Ford's official site - Official Ford Parts Site | Buy Motorcraft & OEM Ford Parts Online | FordParts.com

It says the RT1195 is for the 2002 E450 and the 2007 and newer Super Duties.

 

I just checked O'Reilly's auto parts, They list the motorcraft thermostat RT1195 for my truck also, which is a 190 deg. thermostat. They also have Murray brand thermostats listed for various temps from 170, 180, and 195deg.

If you bought your truck used it is hard to say what is in their.

 

So, do we think the ecm will support each of those different options?

 

That likely will depend on the specific calibration of the PCM.

 

I'd PM Mike or JL and ask them about the stat temp vs pcm relation and see if anything needs to be changed. I don't know why they would put such a cool stat on the truck especially a truck destined for north of the border where its known to get downright cold and nasty.

 

Thanks for the suggestion. I have pm'ed Mike. Here's hoping he is able to help.

 

Heres some date for what it's worth. Ambient temp was 45'F, this was a cold start and truck sat at idle untouched in Park. Coolant temp and gallons/hour readings from an Ultra-Guage. 05 Excursion w/2 valve V-10 all stock 81k miles.
170' = 0.91 g/h
174' = 0.90 g/h
181' = 0.88 g/h
185' = 0.85 g/h
190' = 0.83 g/h
199' = 0.79 g/h
201' = 0.77 g/h
After a 10 mile drive at idle 188' = 0.74 g/h
I thought it would have been out of enrichment by 170' but I guess not. So aside from possible PCM variables I would assume there may be a slight MPG improvement with a warmer t-stat.

 

So I sent a question to 5 star Mike:

"
Hi Mike,

I have a thread going at fordtrucks.com about the temperature of the coolant in my truck and someone mentioned that you might be able to answer a question for me. Coolant temp seems to be running a consistant 173 on my scanguage and I'm thinking that it may have a cooler thermostat installed. I would like to run the stock temp or warmer (maybe 195?) but I'm not sure if the trucks computer will accept or support a thermostat temperature change. Being wizards with tuning these trucks, I'm wondering if you know the answer.

Thanks in advance, and once I have the truck running the way it should, your tuner will be the top of my list.

Thanks Todd

ps. Here is a link to my thread. Feel free to reply there if you wish.
https://www.ford-trucks.com/forums/11...mperature.html

Hi Todd
Honestly i would not fool with a thermostat on your truck."

Not sure what to make of this.

Thanks for the info Tom. Not really sure to make of it. It's becoming clear to me that something is not normal with my cooling so I'm going to buy a new thermostat and change out the old one. Just not sure which stat I should be getting as there are so many different temps listed.

 

Well then pick up a direct replacement thermostat for your year truck and put it in. Maybe your current stat is not functioning properly causing the low coolant temp or your sender is giving readings that are off.

 

I have a 99 F350, SC, DRW, V10, my heater was not warming the truck very well and my mpg's were down. I replaced the T-stat which is a stock Ford at 195 deg's. My mileage went up about 1+mpg's and of course the cab was warmer. Towing in 100 deg weather with 13K 5r, my scangauge went up 215 on a couple of ocasions runs smooth with 352K on the odometer.

 

Ok, I'm going to install a new thermostat today (in the pouring rain - grrr) and I want to double check something beforehand. The parts store thermostat comes with a rubber O-ring but not a gasket. The counter guy said he doesn't have a list for one. Do I need a gasket or does the O-ring do that job? Thanks.

 

The O-ring is what you need.