1998 dodge ram 1500 heater wont heat up

Im experience intermittant heating in my truck. After truck has ran for several minutes it will warm up then start blowing cold air. Is this the thermostat? Also the temp gauge goes hot and then goes right
back to normal. Is this going to cost me a fortune to get fixed? thanks.
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Did you check the coolant level?
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"dr9" < snipped-for-privacy@www.autoforumz.com> wrote in message
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Suspect a sticking thermostat.... it will close off when completely cold, and will open at 195F (or higher), but won't close again as the temp drops around 180F or so. I'd start with replacing the thermostat - <$10 and about 30 minutes worth of work - and go from there.
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