Smell in cab despite extending vent!

[joe308]

Like many others, I'm getting a severe diesel or oil smell in the cab when at idle and the vent is turned on. I know DC installed a crankcase filter / vent on the 03's (not sure if it was meant to fix this). I even extended the vent hose from the fron differential area back to the rear of the vehicle but the smell remains. Is there no fix - what am I missing?

 

[y-knot]

You probably have a small leak somewhere between the turbo and the exhaust flange. I think it is pretty common, they are made of two different metals, and there rate of expansion and contraction is different.

 

[Briman]

I don't know why, but I always get an oil smell for a short time (100 or so miles) after an oil change. Some oil is stinkier than others. The smell ends up going away until the next oil change.

 

[radar doctor]

OIL SMELL

OK on the Flange, Is dodge going to fix it ? What's next???

 

[DBVZ]

I have been to two dealers on this issue, and called a third. The only advice I was given is to run with the AC in the recirc positions instead of the vent positions. Like that, I get little or no cab smell.



Let me know if you get DC to do anything to fix this problem, and what will fix it.

 

[Badunit]

If it's diesel (not oil) then you may have a leak.



If you have less than a few thousand miles on your truck and you're smelling something like oil, 99% of it will go away with a few more miles. I've read that it is a coating on the engine but I don't know if that's what it is or not. Whatever it is, it burns off after a while.



After an oil change I'll get an oil smell that goes away after a few hundred miles. Occasionally I'll get a whiff between oil changes. I've grown to like it.

 

[RJ2]

I thought all Dodge diesels have to be on recirculate not to smell diesel.

 

[y-knot]

I think this has been an issue since the 1st generation truck. Call it a nuance, characteristic of the diesel, what ever you want. I notice it on start-up, and on cool now. Which makes since, my theory is the metal expand and contract at different rates, so you have a cast (thick, dense) part heating and a steel flange (thin, hollow). The steel part heats and expands faster then the cast part, so a small leak develops. Same on cool down, just reversed. I assume if you were to insert a donut gasket between the two, it would help.

 

[Joseph Donnelly]

12 valve engines had a road draft tube from the left rear area of the engine, about a 1" clear plastic tube that ended just above the front diff if a 4x4. 24 valves had the vent on the front--the gear case cover, also a simple hose. third gen engines send the crankcase fumes to a filter under the black plastic cover that is above the valve cover. I smelled oil for a short while, but not since. In general, you can smell a bit of oil--the more volative portion--just after an oil change.

 

[kompressor]

I just took delivery of a '04 and I have a a smell that really doesn't smell like diesel. It is pulled in through the ventalation system and seems to more noticable after the engine warms up. Maybe Badunit has the answer in that it is a coating on the engine. I see that the exhaust manifold shield has a shiny coating on it, maybe it has to burn off.

 

[Tony T.]

Originally posted by kompressor

I just took delivery of a '04 and I have a a smell that really doesn't smell like diesel. It is pulled in through the ventalation system and seems to more noticable after the engine warms up. Maybe Badunit has the answer in that it is a coating on the engine. I see that the exhaust manifold shield has a shiny coating on it, maybe it has to burn off.

kompressor: I think your referring to the same smell I've always questioned, not really a diesel or oil smell something different. For the life of me it's almost a formaldehyde type smell, and the reason I say that is when my travel trailer was new it had the same type of smell to it. I would have to research back through my literature on the travel trailer, but I know I read something in there about formaldehyde being used in it for some reason. I know now since the trucks got more miles to it I don't notice the smell only every once in a while. Oo.

 

[joe308]

What's fustrating is that it appears not to be coming from the vent tube (evidenced by my nice extension not correcting the smell). I have about 7500 miles on her and have changed the factory oil with Rotella a while back. My 94 CTD only did this immediately after an oil change, then it went away - and it had no breather filter. Apparently this won't go away regardless of type of oil or number of miles. Sounds like the seal theory to me. Or, could it be the filter is restricting the crankcase blowby forcing it out somewhere else??? The blowby seems far less coming from the breather tube in my 03 than my 94 - just a thought...

 

[ttreibel]

I don't know about you guys but mine smell comes from the exhaust pipe. I have learned to quickly change the venting or turn the fan off automatically when I hit a red light kind of like shifting into first reaction I guess... ...



I passed it off because the truck is a quad cab with a short bed and I seem closer to the exhaust tip than my old ride... .



The new emission engines blow less smoke but in my opinion stink way more. I agree that they smell more right after an oil change that is were I am at now.



Fresh Oil = less smoke more smell

Old oil = more smoke less smell

but I only have 16K on the truck it's to early to tell yet.



I will buy a cab air filter if they market one however.

 

[Elite1]

Originally posted by Joseph Donnelly

12 valve engines had a road draft tube from the left rear area of the engine, about a 1" clear plastic tube that ended just above the front diff if a 4x4. 24 valves had the vent on the front--the gear case cover, also a simple hose. third gen engines send the crankcase fumes to a filter under the black plastic cover that is above the valve cover. I smelled oil for a short while, but not since. In general, you can smell a bit of oil--the more volative portion--just after an oil change.

My 03' has a vent hose, similar to what my 96' had... is it different?... btw: the 96' never had fumes in the cab, but the 03' does, it is worse with rotella, but still quite noticeable with dello... if I put the air on recirculate the smell goes away.

 

[RonWeiss]

My new 03 has the same problem, fumes getting into the cabin when the vent is selected for outside air, usually when stopped at a light.



I tried extending the vent tube and that didn't help at all. Now that I think about it that vent hose going down the side of the engine is just for leading any condensed fumes to the ground. The breather itself which lies under the valve cover hood lets the out-gassed fumes escape under that hood.



I emailed Cummins on the problem and they mentioned a few things. One was the very poor sealing on the hood seals, especially by the windshield (thats where the intake vent is located) but adding more rubber insulation making the seal tight didn't do much, maybe as a test I should tape off the gap around the whole hood and see.....



Another thing they mentioned is that it goes away after awhile, and it does seem to be diminishing, at least it's less after 3,000 miles. Why? who knows? unless it is just the fumes from the engine coating burning off.



Ron W.

 

[HVAC]

8000 miles plus now and the oil smell is gone. Surely it has something to do with the rings seating.

 

[RonWeiss]

Could be, as the engine breaks in it would generate less blow-by, I guess in 400,000 miles I'll start getting the smell again



Ron W.

 

[brillmtb]

It seems to be exhaust, it stops in recirc mode and it has not changed since day one

 

[joe308]

It stops in recirc because it's not sucking in outside air from the cowl area, just above the valve cover where the stink is eminating from. Is it true that the filter is not connected to the breather tube??? Oh well, I have 7600 mi on mine so we'll see about the break theory shortly.

 

[Elite1]

My truck has 14,000 on it and the rings should be seated the way I drive. But I still have the smell when I come to a stop light or at idle. Only when the vent is on, goes away when switched to recirculate.

I wonder if this product sold by Geno's would help, it is on page 10 of the catalog, it is called the "cab fresh filter kit" ... . it says the 2003 model will be available soon.