Background Info: Backyard mechanic since 1965
Have rebuilt/overhauled serveral engines Would like to hear from professional and hobbyest mechanics. Problem as follows:

Aug. 2001 replaced thermostat on 4.2 liter v6 engine in 99 F-150. Used truck from then to now (march 2002) when it started to overheat again. Decided to have Ford dealer look at it...they decided it was thermostat and replaced it, said the thermostat that was in there was put in "backwards" and that is what is causing overheating.

Argued with them that this is just not possible, I used the truck to go to South Dakota twice which is a 1800 mile trip oneway, and on one of the occasions I hauled a u-haul filled a 16 footer also use it everyday for work.

Payed for repair, got 3 miles overheated again, returned to dealer, tore down to water pump, water pump good, now testing radiator.

Now the million dollar question: Is it possible to run the truck all this time and NOT, I repeat NOT have an overheating problem until now with the thermostat "supposedly" in backwards.

Thanks in Advance.

 

hello major having similar problem and was wondering did you ever find out what was causing your engine to overheat, sure would like to know, thanks from the Dawg.