i have a 2001 dodge ram 1500 3.9l v6 140,000

i am having issues with the truck wanting to stall but doesnt. it's losing power on the smallest of hills to climb. when the truck has been running for a while and go above 55mph it starts blowing white smoke from the tailpipe, its alot of smoke where you can still see it in the air 500-600 feet behind you. i also do not have the fuel mileage i used to get. i fill the tank or get 1/2 tank and in under 2 days its gone.

i only drive 15 miles round trip a day to work. i put a little over 1/2 a tank in it this morning on way to work, by the time i got to work my fuel empty light came on.

i have had truck checked at auto zone, only thing that came up was a vaccum leak.

I have changed all the plugs, wires, distributor cab, rotor and coil, air filter. i run full synthetic oil mobil 1 5w30 for high mileage.

i have checked the anitfreeze, oil, transmission fluid and i am not leaking anything or burning anything. all my fluids are still full. I'm thinking about not even messing with it and just get a new motor and transmission with having 140,000 miles.

 

I can't say for certain, but it sure sounds like more than a vac leak. From the smoke description I would lean towards a leaking head gasket or cracked head & water getting into the engine, but that should show some signs, like low oil or low water/antifreeze, or discolored funky oil or water in the reservoir.

 

Well a vacuum leak will make your truck wanna stall.. so find the leak and fix it.
If your blowing white smoke, you're burning something. Have the cooling system pressure checked and recheck tranny fluid; warmed up truck, in neutral, on level ground.

As far as the mpg drop and choked engine, I would be checking the intake for a blown plenum gasket, clogged cat, and bad o2 sensor. See the Plenum Gasket thread at the top of the 2nd gen forum for info. It would also be possible that burned tranny fluid or coolant has ruined your o2 sensor and decreased your fuel economy.

 

it's not showing any signs of low oil or discolored water/oil in reservoir, my oil pressure gauge always reads about 60-80. i hardly have to add antifreeze. i check it twice a month and havent had to add any since the end of july. it's still full. same with oil i check it twice a month. i haven't had to add oil since my last oil change. which will need change at the end of the month.

i though head gasket to, but with not losing fluids or no fluids mixing together.

 

It's easy enough to pull the throttle body and check for oil so do it.
Rent a coolant pressure tester or even an analyzer to check for pressure leaks/exhaust getting into coolant. Check tranny fluid correctly.

As for no power, pull the front o2 sensor and see how it runs under load. Any better? Then your cat is clogged, likely due to burning oil or possibly coolant.

 

Unless someone sea foams your truck everyday you can't blow giant clouds of white smoke without burning something.

Any chance you're getting really really really bad gas? Sounds crazy but if you're really not losing any fluids....

 

This is what I was thinking as well..... to much water content would have a serious negative impact on fuel mileage, and would account for the white smoke, with no related fluid loss. All that moisture has to be coming from somewhere.

Pull the fuel line from the rail. (special tool needed.) Have someone cycle the key a couple times, and collect the gas in a clear glass jar. Set it on a shelf for a few minutes, and see what separates out.

 

i only use one gas station. sheetz, i never put anything other gas in my truck.

 

Do you drive your truck everyday or does it sit for long peripods of time?