Hello,

Since these forums are always so helpful, I'm going to see if I can get some feedback from the masses. I really do not intend to start a 'this brand is better than that war'.

I have to take my 03 in next week to see if they can find a mysterious exhaust leak. I've checked over the horizontal portions of the exhaust a number of times. I can't see a thing that looks out of place. I'm suspecting it is up around the UP/DOWN pipes and/or with the turbo.

I've been looking about here in the forums to see if anyone has asked this before, but I didn't come across anything.

If the mechanic calls and tells me that I need to replace any of these items, I would like to get some suggestions on what upgraded parts may be used in place of the OEM parts. It seems like for close to the price of OEM, you can do some reasonable upgrades, maybe I'm wrong.

I've seen prices for replacement turbos in the high 1000's, and I've also seen upgrade kits for a little more than that. I tried to get my head around all the possibilities regarding turbos, but I'm pretty sure that's a life-long journey.

As far as the up/down pipes go, there's a member on here who sells units. I'm not sure if I would have to make other changes to be able to use his replacement parts, if anyone has any experience in this area I'm all ears. This same vendor also offers exhaust manifolds of improved design. Is it a waste of time to improve the up/down pipes without the manifolds?

Any other input related to this area would be appreciated.

Thanks,

Well I see lots of folks found my thread interesting but didn't provide any feedback. :(

I guess that's a good thing since I apparently didn't have an exhaust leak after all.

The shop determined that what I was smelling was 'fumes' (supposedly exhaust fumes) coming out of the breather vent. Seems unusual that there would be exhaust fumes in the crankcase though.

Their solution was to extend the breather tube to a location that would have more air circulation.

I just had a short drive home from the shop and it seems better. I guess time will tell.

Does this make any sense to you folks out there?

Is it indicative of an upcoming failure?

Thanks for the reads.

The shop determined that what I was smelling was 'fumes' (supposedly exhaust fumes) coming out of the breather vent. Seems unusual that there would be exhaust fumes in the crankcase though.

Their solution was to extend the breather tube to a location that would have more air circulation.

Is it indicative of an upcoming failure?

Thanks for the reads.

Yes, there are exhaust fumes in the crankcase. The piston rings don't work perfectly on any engine, and you get what we call blow-by. Its all the fuel and air that makes it's way down past the rings and into the case. That's why we have ventilation and PCV systems, otherwise the accumulation of pressure will eventually blow your seals.

Since your truck just vents into the atmosphere it is perfectly plausible that the fumes could make their way into your cab vents.

Too much blow-by on the other hand could be indicative of bad piston rings. I'm pretty sure that the shop would have been able to tell if it was excessive or not. You should be fine.

I'd recommend doing oil samples when you change your oil, this will let you know if there is anything excessive in your oil.

Thanks for both replies.

I'm feeling better about the 'blow by' thanks to Wes' explanation. It makes sense that some exhaust would make it past the rings. Wasn't thinking about that before I posted.

I just had oil analysis done a few weeks ago, it came out great with the exception of having a little silicon in the oil. This was a sample from the oil that was put in when the injectors were replaced, so we'll see what the next change/sample brings. The analysis place indicated that the silicon levels could be high due to sealants used to replace the injectors.

Out of curiosity, I had the shop also check the balance rates and they said they were all within spec. I would hope so, but I've heard of folks who have had 'new' injectors installed only to have problems with the replacements right away.

As always, you guys come through.

Thank you very much for the information.

I don't know what to tell you about the injectors except to keep an eye on your truck. I'm still new to the Duramax world so I'm still learning about them myself.

Glad I could help ease your mind a bit though. Better to not think before you talk than to not think before you're stuck on the side of the road.

Where is this breather vent???!!! I get damn near smoked out of the cab when at a long light.

Where is this breather vent???!!! I get damn near smoked out of the cab when at a long light.

On my '02 it drops down in the front of the motor right beside the EGR vacuum pump. Just a metal tube that vents under the truck.

This is a band-aid fix though, if you can smell fumes in the cab, you probably have another issue - like fuel in the crankcase. Either a return fuel line or injector leaking. I never had fumes prior to having diesel in my crankcase.

If there were fuel in the crankcase, wouldn't that be obvious during oil changes?

It would be super obvious. I work at a fast lube and we have had two with bad injectors come in. I pull the plug and it comes out in a spray not a solid stream. Smells like diesel fuel real bad also.