LML Duramax Up Pipe

Why Does Your 6.6L Duramax LML Need an Up Pipe?

Soot and Carbon Buildup in the Intake Tract

The factory up pipe carries the EGR riser that routes exhaust gas back toward the intake. Over tens of thousands of miles that flow leaves a hard crust of soot and carbon through the riser, the EGR cooler, and the intake, choking airflow and dulling throttle response. An up pipe built to delete or bypass that riser cuts the recirculated soot at the source and keeps the intake path clean.

Thermal Fatigue and Cracked OEM Bellows

The stock pipe uses a thin flex bellows that sits between the exhaust manifold and the turbo, right in the hottest part of the exhaust path. Heat cycling, vibration, and constant thermal expansion fatigue that bellows until it cracks at the weld, and once it cracks the truck pushes exhaust out instead of through the turbo. A T304 stainless up pipe with heavy-duty convoluted bellows and precision TIG welds absorbs that movement without splitting.

Lost Drive Pressure and Sluggish Turbo Spool

A cracked or leaking up pipe vents exhaust before it reaches the turbocharger, so drive pressure drops and spool gets lazy. Customers feel it as lag off the line and EGTs that climb under load. Sealing that leak with a clean stainless pipe puts drive pressure back where it belongs and wakes the turbo up.

What Can an Up Pipe Solve?

Restore Turbo Drive Pressure and Spool

A sealed T304 stainless up pipe sends the full column of exhaust into the turbine, restoring drive pressure and sharpening turbo spool so the truck comes alive off idle and holds boost under a heavy trailer.

Lower Exhaust Gas Temperatures

When drive pressure is right and exhaust flows clean, the turbo breathes easier and EGTs come back down. That headroom matters for trucks that tow heavy, run hot tunes, or work in the heat all day.

Remove the EGR Riser Leak Point

Our LML EGR delete kit with up pipe replaces the failure-prone EGR riser section with a clean stainless pipe, deleting EGR flow and eliminating the crack-prone riser in one bolt-on job.

Shop LML Duramax Up Pipe by Chevy GMC Engine & Fitment Guide

• EGR Delete Kit & Up-Pipe for 2011-2016 6.6L Duramax LML - Fits the 6.6L Duramax LML in 2011-2016 Chevy Silverado 2500HD / 3500HD and GMC Sierra 2500HD / 3500HD. Deletes the EGR riser and replaces the cracked factory pipe with a T304 stainless up pipe, gaskets included, to kill the exhaust leak and cut recirculated soot at the source.
• Bolt-On Passenger Side Up-Pipe w/ Gaskets - Fits 6.6L Duramax LB7 (2001-2004), LLY (2004.5-2005), LBZ (2006-2007), LMM (2007.5-2010), and LML (2011-2016) in Chevy Silverado 2500 / 3500 and GMC Sierra 2500 / 3500. Direct bolt-on T304 stainless replacement with high-temp gaskets that drops in where the factory bellows cracked.
• Duramax Up-Pipe Set for 2001-2016 LB7 LLY LBZ LMM LML - Fits the full 6.6L Duramax family from LB7 through LML in 2001-2016 Chevy GMC 2500 / 3500 trucks. CNC laser-cut flanges and precision TIG welds restore sealed exhaust flow across every generation of the 6.6L.

Why Choose EGR Performance?

The industry standard for high-performance diesel reliability.

Premium Quality & Rigorous Testing

Our EGR, DPF, and CCV delete kits are engineered from premium-grade materials and subjected to brutal quality control and field testing. Unlike generic alternatives, our products are built to withstand extreme heat and pressure, delivering unmatched durability and long-term stability when your rig needs it most.

20 Years of Proven Diesel Expertise

We aren't just selling parts. We live in this industry. With two decades of hands-on experience providing specialized modification solutions for heavy-duty truck owners, our upgrades have been extensively proven across every driving environment, from daily towing to high-performance tracks.

Industry-Leading Standards

We work hand-in-hand with top-tier industry partners and reputable organizations. Every product we design, test, and ship meets or exceeds strict industry standards, ensuring your Powerstroke, Cummins, or Duramax gets the exact precision it deserves.

Real Results, Proven Track Record

Thousands of diesel owners trust us to unlock their engine's true potential. Our massive library of positive customer feedback and successful build case studies proves one thing: our kits deliver real horsepower, lower EGTs, and flawless reliability in the real world.

What does the up pipe do on a 6.6L Duramax LML?

The up pipe routes exhaust gas from the passenger-side exhaust manifold up into the turbocharger inlet, and on the LML it also carries the riser that feeds exhaust to the EGR system. That column of exhaust is what spins the turbo, so a sealed up pipe is what builds drive pressure and spool.
It also runs the hottest exhaust in the engine bay, which is exactly why the factory bellows fatigue and crack over time.
Upgrading to a T304 stainless up pipe keeps that exhaust path sealed and the turbo fed.

Why does the factory LML up pipe crack or leak?

The stock pipe uses a thin flex bellows placed right between the manifold and the turbo, in the hottest and most vibration-heavy part of the exhaust. Years of heat cycling and thermal expansion fatigue that bellows until it splits at the weld.
The EGR riser welded into the same pipe cracks for the same reason, and soot blows out around the split.
A T304 stainless up pipe with heavy-duty convoluted bellows and precision TIG welds absorbs that movement without cracking.

What are the symptoms of a cracked LML Duramax up pipe?

The classic signs are a ticking or hissing noise under the hood, a whistling sound under load, and black soot baked onto the pipe near the bellows or riser weld.
Because the leak is before the turbo, you also feel lazy turbo spool, slower boost, and EGTs that climb when you tow.
It is an exhaust leak, not a boost leak, and the soot trail usually points right at the crack.

Do I need to replace the up pipe when I do an LML EGR delete?

Yes, and most Duramax techs recommend doing the full up pipe replacement with the delete instead of just a block plate. The EGR riser that the delete removes is built into the factory up pipe, and that riser is one of the most common crack points on the LML.
Our LML EGR delete kit with up pipe replaces that whole section with a clean T304 stainless pipe, so you delete EGR flow and remove the leak-prone riser in one job.

Will an LML up pipe upgrade lower EGTs and improve turbo spool?

A sealed T304 stainless up pipe puts the full exhaust column into the turbine instead of leaking it under the hood, which restores drive pressure and sharpens spool.
When the turbo breathes correctly, exhaust gas temperatures come back down, which gives you headroom for towing, hauling, and hotter tunes.
Most owners notice quicker boost response off idle right after the swap.

Is the up pipe the same on all 2011-2016 LML Duramax trucks?

The passenger-side up pipe uses the same fitment across the full LML generation, 2011 through 2016, on both Chevy Silverado 2500HD / 3500HD and GMC Sierra 2500HD / 3500HD.
That means the 2015 Duramax up pipe and the 2016 Duramax up pipe take the same part as the 2011 trucks, so just confirm your engine code.
Some of our up pipes also cover the earlier 6.6L Duramax family, including LB7, LLY, LBZ, and LMM from 2001 to 2010, so check the fitment on each kit before you order.

Are stainless steel up pipes better than the factory OEM pipe?

For a working Duramax, yes. The OEM pipe is built to a cost with a thin flex bellows that fatigues and cracks, while a T304 stainless up pipe uses a heavier convoluted bellows, laser-cut flanges, and precision TIG welds that hold up to repeated heat cycling.
Stainless also resists the corrosion and soot attack that eats the factory pipe.
The result is a sealed exhaust path that keeps drive pressure on the turbo for the long haul.

Can I just re-weld my cracked factory up pipe instead of replacing it?

You can weld the crack, but most techs will tell you it cracks again, usually right next to the weld, because the bellows is already fatigued and the metal is thin and soot-contaminated.
Re-welding is a band-aid that buys you a few months, not a fix.
Replacing the pipe with a T304 stainless up pipe removes the fatigued bellows entirely and gives you a clean, sealed path that will not crack at the same spot.

Do LML up pipe kits come with new gaskets?

Yes, our LML up pipe kits ship with high-temperature gaskets so you can seal the manifold and turbo flanges on the first install.
We always recommend replacing the LML up pipe gasket when the pipe comes off, because the old gaskets are usually heat-hardened and will not reseal cleanly.
Kits with gaskets included mean you do the job once instead of waiting on parts halfway through.

Is an LML up pipe with EGR delete legal for my truck?

An EGR delete kit with up pipe is intended for competition and closed-course off-road use only, because removing emissions equipment breaks federal and state emissions laws for on-road vehicles.
Confirm your engine code and year before ordering, since our up pipes fit 2011-2016 6.6L Duramax LML trucks and some also cover 2001-2010 LB7, LLY, LBZ, and LMM engines, and the fitment must match your build.
We back every order with fast and free shipping, a 1-year warranty, and a 45-day return policy so you can buy with confidence.