SPOOLOGIC Turbine Shaft 10 Blade

The SPOOLOGIC Turbine Shaft 10 Blade SL-240-021 is an OEM-spec replacement turbine shaft for the GT3788VA turbocharger on 6.6L LLY Duramax applications. Built to factory geometry — same 10-blade High-nickel Inconel turbine wheel, same shaft length, same compressor-end thread — so the new shaft drops into the bearing housing and accepts the original compressor wheel and lock nut without modification. This is a direct OEM-spec replacement only — no performance changes to blade count, trim, or geometry.

Features

• OEM-spec 10-blade turbine wheel — same blade count, trim, and exducer diameter as the factory shaft it replaces
• High-nickel Inconel turbine wheel — holds strength at sustained EGT
• Friction-welded shaft and turbine wheel assembly
• Machined compressor-end threads for the compatible compressor wheel and nut
• Shaft journal and seal lands machined to OEM dimensions for clean bearing housing fit
• Service-replacement part — built for rebuilders restoring a damaged or worn factory shaft to original spec

What's Included

• Turbine shaft and wheel assembly — 1

Fitment

• 2004.5-2005 Chevrolet Silverado GMC Sierra 2500 3500 6.6L Duramax LLY

OEM-Spec Replacement, Not a Performance Upgrade

This shaft is a service-replacement part built to the original turbo's specifications. Same blade count, same wheel trim, same shaft dimensions, same material grade as the part it replaces. It is the correct choice when a turbine shaft is bent, scored on the seal land, or the wheel is damaged from a foreign object event and the rest of the CHRA is still serviceable. It is not a performance-trim wheel and will not change spool, flow, or top-end power compared to a healthy stock shaft.

Turbine Wheel Material

The High-nickel Inconel turbine wheel withstands high exhaust temperatures. The shaft is alloy steel, friction-welded to the wheel to form the turbine shaft assembly. Compressor-end threads are machined to OEM spec so the original compressor wheel and lock nut torque correctly during reassembly.

Turbine Specifications

• Inducer: 72.5 mm
• Exducer: 66.4 mm
• Blade count: 10

Installation Notes

The turbine shaft is individually balanced. Balancing the assembled rotating assembly is recommended best practice. Follow the applicable service specifications for compressor-wheel nut torque, shaft endplay, and bearing clearance.

OEM and Manufacturer References

• 736554-0015, 740659-0010, 759622-0005, 97387896, 98011735

⚠️ DIY Product — All Sales Final, No Warranty, No Returns

This SPOOLOGIC turbocharger repair product is intended for experienced turbo builders and qualified technicians. Proper installation requires suitable tools, careful inspection, and correct assembly. All sales are final—no warranty, returns, or exchanges. Confirm compatibility before ordering. See the SPOOLOGIC Warranty Policy for details on products sold without a warranty.