How to Remove an LBZ Duramax Turbo Heat Shield

The Short Answer

On an LBZ Duramax, the turbo heat shield is a metal cover that sits over the hot side of the turbocharger to protect nearby wiring, hoses and components from radiant heat. The LBZ is the 6.6-liter Duramax diesel used mainly in 2006 and 2007 Chevrolet Silverado HD and GMC Sierra HD pickups, including the 2007 Classic body style, as well as some medium-duty trucks. To remove the shield, let the engine cool completely, then remove the intake components that block access to the top rear of the engine. After that, remove the small fasteners that hold the shield, and lift it out without damaging the surrounding parts. The main factor that changes the job is fastener condition. Heat-cycled bolts on or near the turbo can seize or snap, and a broken fastener in a turbo or exhaust component changes a simple removal into a repair.

This guide applies to the LBZ engine only. Other Duramax generations, such as the LB7, LLY and LMM, use different turbo, intake and shield arrangements, so do not assume their procedures or parts carry over. Body style, chassis type and aftermarket intake or turbo parts can also change the access path. No manufacturer service procedure, fastener count, fastener size or torque specification was supplied for this article. Where those details matter, they are marked below as items to confirm in GM service information for your specific vehicle.

Before You Start

The LBZ turbo sits at the top rear of the engine, toward the firewall, under the intake plumbing. Working on it means reaching over the engine. The following prerequisites keep the job safe and prevent avoidable damage.

Engine fully cool: the turbo and exhaust parts stay hot long after shutdown and can cause serious burns. Wait until the turbo housing is cool to the touch. Service information: obtain the GM service manual procedure for your model year and chassis to confirm the removal sequence, fastener locations and reinstallation torque values. Battery: disconnecting the negative battery cable is a sensible precaution when you are working around harness connectors. Check the service information to see whether the procedure calls for it. Replacement parts on hand: plan for possible replacement of fasteners, clamps or seals that may be damaged or become unserviceable during removal. Confirm part numbers for your vehicle with a parts supplier or dealer. Clean work area: turbo inlets and intake openings must stay free of debris. Have clean caps, plugs or tape ready before you open anything.

Tools and Supplies

Exact socket sizes were not supplied and may vary with production changes or previous repairs. A general set suited to this kind of under-hood work includes the following items.

Metric socket set with short and long extensions and a universal joint; Ratchets, including a low-profile or flex-head ratchet for tight spaces near the firewall; Screwdrivers or a nut driver for hose clamps; Penetrating oil for heat-seized fasteners; Torque wrench for reinstallation; Intake opening covers, such as clean caps, plugs or tape; Work light or headlamp; Gloves and eye protection; A magnetic pickup tool for dropped fasteners

Step-by-Step Removal

The sequence below describes the general order for gaining access and removing the shield. Confirm each step against GM service information for your truck. Intake routing and component placement can differ between configurations, and aftermarket parts may add or remove steps.

1) Confirm the engine is cool and the truck is parked securely with the ignition off. If the service information calls for it, disconnect the negative battery cable. 2) Remove the engine cover, if one is fitted. 3) Loosen the clamps on the intake tube between the air filter housing and the turbo compressor inlet. Disconnect any sensors or hoses attached to the tube, then remove the tube. Label connectors and hoses if you are unsure where they return. 4) Immediately cover the turbo compressor inlet. Any object that falls into the inlet can destroy the turbo when the engine starts. Stop and retrieve anything that drops in before you continue. 5) Remove any other intake ducting, brackets or components that block the shield, as the service information directs for your vehicle. Keep the fasteners from each part separate. 6) Locate the fasteners that secure the heat shield. Before turning them, inspect each one and apply penetrating oil to any that look rusted or heat-scaled. Allow the oil time to soak in. 7) Loosen each fastener with steady, controlled force. If a fastener does not turn with reasonable effort, stop. Reapply penetrating oil and try again later rather than forcing it. A fastener that snaps off in a turbo or exhaust component usually has to be extracted, which may require partial disassembly or professional help. 8) Once all fasteners are out, ease the shield free. Guide it past the wiring, hoses and sensor leads so you do not pull or crack anything, then lift it out. 9) Inspect the shield for cracks, broken mounting tabs or heavy corrosion. Also check the nearby wiring and hoses for heat damage. A damaged shield should be replaced rather than reinstalled.

When to Stop and Get Qualified Help

Shield removal is generally within reach of a careful DIYer. A few situations, however, call for a qualified diesel technician or a shop with the right extraction tools.

A fastener breaks off in the turbo housing, exhaust component or other threaded mount. Threads strip or a mounting point cracks. You find heat-damaged wiring, a melted connector or evidence of an exhaust leak. An object falls into the turbo inlet and you cannot retrieve it. You find oil around the turbo or damaged turbo components that suggest the turbo itself needs service.

Reinstallation and Completion Check

Reinstall the shield before running the engine. The shield exists to protect nearby parts from turbo heat, so driving without it can damage wiring and hoses. Torque values for the shield and intake fasteners were not supplied. Use the specifications from GM service information rather than estimating them.

Position the shield so it clears all wiring and hoses, then start every fastener by hand to avoid cross-threading. Tighten the fasteners to the specified torque. Remove every cover from the turbo inlet and intake openings, and confirm that nothing was left inside. Reinstall the intake tube and any other removed components. Seat each clamp properly and reconnect all sensors and hoses. Reconnect the battery, if it was disconnected. Start the engine and listen for rattles, which can mean a loose shield, or for whistling, which can mean an intake leak. Check for warning lights. After a drive, once the engine has cooled again, recheck the shield and clamps for looseness and look for any discoloration on nearby parts.

What This Guide Could Not Confirm

Several details were not available for this article: the number and size of the shield fasteners, reinstallation torque values, part numbers, and whether battery disconnection is required. These may also vary by production date, chassis type and prior repairs. Confirm them in GM service information or with a dealer before you start, especially the torque specifications and the parts you will need.