Quieting the Ford 7.3 Powerstroke

[CHEESE_WAGON]

Originally Posted by o1marc

Normal operating temp is 190, not sure you want to, or can keep it at 170. If you want the fan on later, get an adjustable thermostat for the fan. I suspect a gauge is off if it sits at 170.

Or a sticking thermostat. I had an Impala that kept throwing coolant temp codes for no apparent reason, noticed the engine ran at 170 all the time, and wouldn't warm to over 155 if I didn't let it warm up. Come to find out the thermostat had been 'modified'. Engine had been replaced, and the donor car's previous owner had bent the edges of the thermostat to allow a constant trickle flow. PCM didn't like that apparently, but it did make the engine run cooler. However, I will offer that diesels tend to burn cleaner at higher temps to a point. Fine line to walk.

[cadillackid]

The stat on my 444e got stuck open about 1/3 a couple winters ago. Wouldn’t warm above 135 in town or 160 on highway. Of course the fan didn’t run

[Mekanic]

I had to cover the inside of my F-700 with dynamat. THe trick i used was Bestbuy will match prices on Amazon (at least they did a 3 or 4 years ago) s long as amazon is the seller. THey used to sell "Dynamat door kits" at best buy for $120 and I would buy em for the matched price at $58