Start Up Question

Ok, so I'm new to the forum, I just purchased a 2000 Silverado 1500 Z71 at the end of May. What more can I say, I love it. It has the 5.3 with 90,000 miles. Now, regaurdless of what anyone has replaced on the truck previously, with 100k coming up, what should I replace as far as maintenance goes? I noticed that every once in a while, maybe 1 out of 15 times when I crank it up the next morning after being driven the previous night, white smoke would come out of the exhaust for about 5 seconds and then just stop. It doesn't do it every time, just sometimes. I don't think the smoke is any other color, it seems white in the mirror but could have a slightly light blue tint to it, but I can't tell. I had my exhaust done at a local shop as soon as I bought the truck, but I don't think it has anything to do with that. I just had them cut the whole system off right after each cat, and run straight 2.25in piping from each cat out the back. I'm hoping the white smoke is just moisture that occurs only sometimes.. like maybe after a heavy rain, but I have noticed the occurance of rain when it does it. Any ideas from anyone? Thanks for your help!

Stephen

sounds like just moisture.....and the theory on everything else.....if it aint broke, dont fix it...

I have had my Silverado for a little over 2 years now and it has done the same thing 2 or 3 times shortly after i got it, but it would only do it after driving on the highway and it sat for about 30 minutes to an hour before i started it up again. My dad's truck did the same thing ot him a couple of times but he has a 93 with a 5.7 in it and when he asked a mechanic about it the mechanic said that it was probably the valve seals were cooling quicker than the aluminum heads and a drop or so of oil would get past as the valve seal would cool down and contract quicker than the aluminum heads. That almost sounds like a logical explanation. It has been probably well over a year since mine has done it so i am not too concerned. I would only be concerned if it would do it every time or if it was alot of smoke or smoked even while it was running.

Hope this helps, probably just moisture but its worth it to check it out, just in case. I found this on the net

White smoke: White smoke is caused by water and or antifreeze entering the cylinder, and the engine trying to burn it with the fuel. The white smoke is steam. There are special gaskets (head gaskets are the primary gaskets) that keep the antifreeze from entering the cylinder area. The cylinder is where the fuel and air mixture are being compressed and burned. Any amount of antifreeze that enters this area will produce a white steam that will be present at the tailpipe area.

If white smoke is present, check to see if the proper amount of antifreeze is inside the radiator and the overflow bottle. Also check to see if antifreeze has contaminated the engine oil. You can look at the engine oil dipstick, or look at the under side of the engine oil filler cap. If the oil is contaminated with antifreeze, it will have the appearance of a chocolate milkshake. Do not start the engine if the oil is contaminated with antifreeze, as serious internal engine damage can result.

How did antifreeze get in the oil or cylinder in the first place? The engine probably overheated and a head gasket failed due to excessive heat, thus allowing antifreeze to enter the cylinder (Where it is not meant to be).

It is kinda weird to say but check trans. fluid level. If the trans module goes bad it can force fluid through and cause some white smoke. It happened to one of our grass trucks on the fire dept.

From your description, I don' think you have coolant leaking into the engine.

Moisture will condense in your cats and exhaust pipes over night. The heat and pressure change from starting the engine the next morning will convert this moisture - resulting in white vapor - not to be confused with smoke. Smoke is a product from burning. Vapor is a product from a phase change.

Blue smoke is oil burning. You can smell it. You have 100K - expect it.

Basic Questions:

How does your truck run, cold and heated?
Do you smell coolant?
Do you lose coolant?
How does your oil look?
Do you leak oil or coolant?
Do you use oil?
Do you smell oil burning?
How is your oil pressure?
How is your engine temp - hot?

And last, but certainly not least is black smoke, which is caused by ineffecient (i.e. unburned) fuel combustion. Possible causes are bad plugs, wires, and/or coils.

I have a 00 with a 5.3L I pulled a trailer the other day and when disconnecting the trailer smelled coolant. Thought truck was overheating....gauge read ok...didn't smell anywhere except the lect exhaust outlet. Have looked pretty funny several times since as I go and sniff at the exhaust, but haven't smelled it since.

Any thoughts?