89 f1t0. 4.9 2wd. My temp gauge starts below the C and the hottest it gets is to the o in normal and I know that's hot because it shot to that when I only had a half gallon of antifreeze in it. Ive owned the truck for a year. The temp sender looks new and the person that replaced it used what looks like Teflon tape. Will that cause a grounding problem? Is the temp gauge not going to read right with a newer temp sender? I cleaned the connector on wire. Some wire is exposed but not corroded and the boot was cut off.

 

First lets establish what you are calling "hot"....If the trk is not overheating it likely is a thermostat issue & the guage is reading right....I would replace that as a first thing to do...& Also use a OEM stat !!!.The teflon tape should not be an issue as your gauge is reading....As you do above you could clean & replace the ends of that guage wire (Rock auto & other parts stores can help here)
Other side note is in winter is the heater putting out sufficient heat...if not that backs up the stat change as well ????

 

The heat works great. I replaced the radiator with a narrower one and since then the gauge has gone up to the o almost to r. I'm not sure where the thermostat is
It's definitely running hot. You can smell it and the way the metal creaks you can tell its hot

 

So you are thinking it's overheating ?? Thermostat is very front of the engine & upper rad hose will go into it....Pull the stat....there should be a heat range stamp on it (probably 195 192 or 190) I would test stat....bowl water on your stove as it starts to bowl place your stat into the water....Water bowls @ 212 degrees so a 195 stat would immediately go to full open... Take stat out & it might take a 1/2 minute but it should fully close up again !!!......If you are happy with it's operation I would reinstall it... Both heater hoses should be @ the same temp when you grab each one.....It might be a good idea while apart to back flush your heater core & rad etc... It should run etc. & be okay with the narrower rad (as long as it is not plugged etc)....That's all I have ...Good Luck !!

 

I don't see any problems with your engine overheating since the coolant hasn't boiled over.. My gauge reads halfway or slightly above that on the gauge. No big deal. I don't get hung up on what it displays since it doesn't indicate actual degrees.

 

Does your new radiator have more cores than the original?
I put a 3 core in my van where I took out a 2 core
Now my gauge reads lower, because the temperature is lower

 

Top hose is way hotter than bottom hose. I just drove it for 5 minutes and it's acting way to hot. The top hose is too hot to touch the bottom hose you can grab and hang onto.
it didn't start acting like this until i changsd out the radiator.
temp gauge reads off in my opinion

 

That's the way it's supposed to be, especially on a 85 degree day in Michigan.

 

It is normal for the bottom hose to be cold, and the top hose be so hot you cannot hold on to it for long.
That is why a lower hose lasts about 40 years and the upper hose will need to be replaced periodically
Use an aftermarket capillary tube gauge if you want an accurate temperature reading

 

Sounds like your radiator is doing a good job.