Engine/Transmission (1998.5 - 2002) smoke coming out of oil vent tube

[damon]

First time this has ever happened. I was at a stoplight today and noticed smoke coming out from the front of the truck, kind of whitish-grey like burning oil. I figured it was just that since I've had a slight oil leak ever since the VP44 was replaced but pulled over and checked under the hood, and it is coming from my oil vent tube which is run down behind my front axle.



Oil level and pressure is good and the truck seems to be running fine.



Any ideas ?

 

[lmills]

A little is normal. A lot is blow by. Most likely you are OK. Most people don't notice it and when they do they get worried. Just keep an eye on it.

 

[dresslered]

Perfectly normal. Do a search and route the vent tube back further (i. e. mid transmission area) and you'll prevent the oily build up on the front of your engine and you won't have that terrible smell in the cab after an oil change. I still see lots of smoke from it at times at the red lights and often think that it is from the guy next to me.

 

[damon]

Thanks for the response guys, that's what I was hoping to hear. It really caught me off guard because this is the first time I've noticed it in over 2 years of daily driving.

 

[dresslered]

The real question is how grimey is the front of your engine? Here's an old reprint of a PM I sent to a new truck owner a few years ago when we all noticed the new location of the brather bottle:





To fix the blow-by problem, I wanted to retain the stock "bent" breather tube, so I just bought a 1/2" heater hose adapter. With that, I bought 5' of heater hose and just extended the stock breather. I ran the new hose along the starter cable and then left some slack (to allow for engine movement) while jumping it over to the frame using large tie wraps. I then ran along the frame to about midway of the transmission where I then point it down at the ground. Throw the original bottle in the trash as it does absolutely nothing except catch an occassional drip. I leave my drips on the highway! If you do an oil change prior to this modification, you will be gassed out of the cab as the new additives get burned off! You are not going to believe the smoke that comes out of this hose and will then understand why it mucks up the engine so much.





P. S. San Juan Capistrano: I hear that there are some great places to eat down there?

 

[damon]

Hardly anything on the front of my engine. Luckily, when the truck was nearly new, a local diesel mechanic ditched the bottle and ran a length of heater hose over the top of the engine and down behind the front axle. The mess all goes back there behind me on the road now.



SJC - good fish tacos, plenty of mex food, and you gotta try the "burritos de swallows" :-laf

 

[lmills]

Over the top of the engine? I don't believe you are suppose to do that. I think you are supposed to have a continuous down flow from the engine so that any oil that is blown by can drain out. If he has it turned upward and running over the top side it may accumulate oil.

 

[dresslered]

Good word on the "burritos de swallows" . Also, good to hear that you are keeping your engine clean. I will have to agree with lmills that you don't want the oil to be able to accumulate anywhere however. There are some side covers on the block that can actually blow with the slightest back pressure and they are a pain to replace. Also, I have heard that for the people in the colder climates, the build-up can actually freeze and block the breather completely. Not usually a big issue here in the Sunny state.

 

[damon]

Hmmm, now I'm thinking I should re-route this vent tube. I trusted that the deisel tech from the local dealer would have done it right as he had a very strong reputation in the area.



Thanks for the input.