overheating and burning oil

[perry0771]

I noticed last week my truck was beginning to run a little hot but cooled down after i put the heat up a little so i thought nothing of it and figured i wouldjust have to replace the thermostat. But as of the past few days when i start the truck i have noticed some blue smoke coming from the exhaust. Any answers as to what is wrong would be appreciated.

[kathyricks]

If the cooling system has been filled with aftermarket green or yellow antifreezes and tap water for several years then silicate and calcium carbonate deposits could now be partially blocking the core tubes inside the radiator.

To check, drain a couple quarts of coolant from the radiator and look down at the core tubes. If they are partially obstructed by white deposits then you'll need a new radiator because no cleaners will effectively remove these deposits.

Momentary blue smoke at start up is usually a sign of deteriorated valve stem oil seals caused by infrequent oil changes. However, this is mainly a cosmetic issue and you don't havn't to worry about it as long as the exhaust has no smoke after the engine is warmed up.

[mdbrjb]

Need more info. Did it start doing this all of a sudden? How many miles?

Could be a blown head gasket. Any oil in coolant? Or coolant in oil? Does smoke smell like oil or anti-freeze?

Or as KR said, the two might not be associated. Overheating, bad radiator. And smoke, valve guides/seals. I had a Chrysler that puffed blue when you started it. But it kept going for at least another 80k - or more - sold it.

[perry0771]

Once the engine is warmed up it stops smoking blue. The truck will usually not overheat unless i put it in 4x4 or if the a/c is on. It smells like burning oil not coolant.

[mdbrjb]

Then, it's probably what KR said. Don't go too long with it overheating. Transmissions cook fast!

[kathyricks]

If the engine overheats only during slow moving congested traffic conditions then the fan clutch is likely faulty.

If the engine overheats both on the open highway as well as in congested city traffic then the radiator is likely partly clogged.

If you truck has a bunch of engine mods and chassis mods (like a lift & huge tires) they
could be contributing to the tendency to overheat

[perry0771]

It was the fan clutch. I replaced it and now it works great. Im going to switch to 10w30 oil for the summer to see if that has anything to do with why the truck is burning oil maybe the 5w30 is too light for the summer.