This past weekend I switched out my radiator, thermostat, water pump, and fan clutch (bad pump which blew a hole in my radiator). I got a 160 degree thermostat thinking it would run cooler living in NC. Now my temp. gauge seems to fluctuate between the N and R in normal, as if the thermostat is opening and closing and causing the change. I checked fluid level several times and won't take anymore. Question: can this cause any damage not running at a consistent temperature? Should I just move up to a 180?

Thanks for any help.

 

I put a 160 degree in my truck and the truck would never warn up . The heater in the truck would get warm but not hot . I change the 180 degree and everything's fine again

 

You don't mention year or engine but most trucks with fuel injection are built to run 195` t stats I wouldn't run any less than a 180` mileage and performance as well as emissions will suffer.

 

It's not running well when I first start it but runs fine when its warmed up, I think I'm going to change it to a 180. Thanks.

 

Need mod that get the engine hotter to run cooler tstats. Usually force inducted are the ones that benefit from it.

 

I put a 195 degree in my '96 4.9L and the temp. gauge stays on the N when at normal operating temp. I would imagine a 160 would stay open most if not all the time when the engine comes up to temp.

 

That's why the gauge flutters all the time with 160's. It stays open too much for too long where the 195 is close enough to operating temp that it can regulate the temp better and more effectively.

 

Interesting, a previous owner must have put a different one in my truck (95 with a 351W) My gauge always moves from N to R to N. Never really cared but now I know why. Maybe I will swap that out some time soon.

 

160's are pretty much a high heat heavily mod'd go really fast n hard for a short time type application. Daily driving not so much lol.

 

Apparently I was wrong about my thermostat. I went and picked up a 180 and made the switch tonight. Even though I asked the guy at Autozone to give me a 160, it read 195 on the thermostat. So now I'm confused, even though at Advanced Auto they have that a stock thermo is a 195, and it didn't seem to work well, I put in a 180 and on a test drive it seemed to stabilize. I guess I'll put it to the test tomorrow when I pull a dump trailer. By the way, it's a 96 4.9. I appreciate everybody's input and hope that others on the site will write in and give results of there fixes. It's the only way I've found to repair my truck without worrying about being stabbed by a shop. Thanks again.