Airbox mod?

[Killerbee]

Originally Posted by kowekiller

Wow you did your homework on that one!Good find.So does it make any sense to use and aftermarket filter system like s&b or afe?

Only if it can be demonstrated that they keep down IAT. In my testing and experience, they do not.

I ran an AFE vehicle up the heated grade, and it did no better than stock. But that is mainly due to the fan induced IAT increase. To guard against it, you have to go outside the engine compartment for air, which the donaldson does with limited effectiveness.

From 02-06, after the TSB. the intake box sourced air underhood, and you were insured of nice thin, pre-heated air charge (dumb), and that beat up the induction system with a thermal feedback loop, which led to other problems when the wastegated turbo disappeared, in 04.

[kurt]

this is the tsb i found

2001 Chevrolet and GMC C/K Pickup Models

with 6.6L Duramax™ Diesel Engine (VIN 1 -- RPO LB7)

Condition
Some customers may comment on decreased engine performance/power on the above vehicles with the LB7 Duramax™ Diesel engine. The Malfunction Indicator Lamp (MIL) may be illuminated with DTC P0101/P0103 set. The customer may also note that the "filter minder" on the air cleaner assembly may indicate the filter element needs replacing at very low mileage. These symptoms are more likely to occur when pulling a trailer on wet/slushy roads, but have been reported in heavy rain, at curb weight, during highway driving.

Cause
The LB7 diesel engine creates very high air flow under load. The primary source of inlet air to the engine is through the right front fender. The tires kick up water spray on wet roads which is pulled in with the incoming air from the right fender opening located over the front bumper. This ingested water may soak the airfilter element causing increased restriction. This restriction may activate the "filter minder". If the water continues past the filter, wetting the mass air flow (MAF) sensor, the MIL may illuminate.


Important
If the vehicle is being driven through snowy and/or slushy roads that have been salted, the MAF sensor may be contaminated with soluble road salt.


Correction
Install a revised air cleaner assembly, P/N 25345138, that has a lower incoming air velocity. Also, seal off the right inner fender panel air inlet holes and reprogram the ECM by following the procedure below.



here is the aftermarket intake.


How is this any better? Is it because its primary source of air is not the fender and because it can draw air from just about anywhere?

I see where it can become restricted and cause a lack of performance but that doesn't necessarily mean its letting water into the engine. Its just not letting in enough air.

[Killerbee]

Against water intrusion, the benefit is that there isn't high suction in a water laiden area, it's "open". The narrow openings in the fender, when employed, are subject to high suction, as referenced in the TSB. That is suction necessary to pull heavy water drops toward the element with high velocity. If that suction is reduced, water drops will tend to fall with gravity before reaching the element. The new 06-on intake gives entry air a quick spin, sending drops outward...and eventually out a one-way valve on the bottom of the intake box.

I think most of the problems were code related back then, not so much water ingestion causing engine damage. Water isn't fatal, or even harmful, unless it pours in, as in high water crossings.

It's a nice picture, but the AFE does absolutely nothing for you, with the exception of frequent MAF code reports, and additional cleaning maintenance.

Good for the diner car show...but nothing else. The metal tube speeds conduction air heating as well, FWIW. But does reflect most radiation effects.

[kurt]

that makes more sense. Thanks

[Killerbee]

FWIW, I use an intake that is very similar to the original 01 intake. It is modified with a demand door that only opens under high load (suction). That lowers velocity through those fender openings. Here is a look at the difference between the TSB'd box (red), and this effective CAI (blue). This is for the LLY, not the 06-on intake.

[Tigger]

Ok guys, now I am confused. I just bought a 2003 GMC 3500. With the extreme similairities in GMC and Chevy, I figure I have some filter intake concerns here. Currently the truck has the stock filter box and filters. Is there something I need to be concerned with on the current setup or is this okay to continue running with here?

Thanks for the help.

[BigRedChevy]

Your fine, it is the LLYs that have the restriction in the turbo mouthpiece. The LB7 has a different turbo and mouthpiece on it.