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Old 02-26-2013, 09:30 AM
Hogg Hogg is offline
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The LQ4 6.0 was available on the 1999-2007 GMT800 3/4 ton and 1 ton trucks. 1999 and 2000 LQ4's have iron heads, 2001+ have aluminum heads. The only difference between an Lq4 and an LQ9 is the pistons/rods. The LQ9 uses a flat top piston yielding 10:1 compression, the LQ4 uses a dish piston for a 9.4:1 cr. Same cam, heads, crank, block etc etc, PCM tune is also different.
The 2001 C3 and 2002+ Sierra Denali also used a version of the LQ4 which was rated at 325hp@5000rpm/370 lb/ft torque@400rpm. These had a slightly different exhaust, ar intake and PCM tune.

The 1999-2007 LQ4 was rated at 300hp@4400rpm/360 lb/ft torque@4000rpm. These HD trucks featured a dual 3" exhaust from the manifolds back to the dual in/single out muffler. These trucks were detuned via PCM tuining in order to comply with federally mandated noise laws.

The 2002+ LQ4 was rated at 345hp@5200rpm/380 lb/ft torque@4000rpm.

Cant really diciper what vehicle that engine comes from, unless you had the VIN. So its either a 1/2 ton Sierra Denali(C3) or 1/2 ton HD(heavy half) truck or 3/4-1ton HD truck/Suburban.

I am not seeing that block casting number being used after 2002. Because the engine has teh 4500 trans,I'd surmised its from a 1999-2002 3/4 ton ton HD truck as thats teh only vehcile that uses teh LQ4 and the NV4500 trans.

here is the GM info on the trans
Rear wheel drive, five-speed manual transmission
Engine Range:
5.7L - 7.4L

Maximum Engine Torque:
460 lb-ft

Gear Ratios:
First: 5.61
Second: 3.04
Third: 1.67
Fourth: 1.00
Fifth: 0.75
Reverse: 5.04

Maximum Validated Gross Vehicle Weight:
6804 kg

Case Material:
Aluminum and Cast Iron


Center Distance:

Fluid Type:
Castrol Syn-Torq Synthetic oil

Transmission Weight:
97.1 kg (wet)

Fluid Capacity (Approximate):
3.78L (Dry)

Power Take Off:
Yes. One - Both Sides

GMC Sierra and Chevrolet Silverado(2500 HD and 3500 series)

Same for the LQ4 engine
Vortec 6.0L V8

Compression Ratio:

Valve Configuration:
Overhead Valves (2 valves per cylinder)

Assembly Site:
Romulus, Mich.
Silao, Mexico

Valve Lifters:
Hydraulic Roller

Firing Order:
1 - 8 - 7 - 2 - 6 - 5 - 4 - 3

Bore x Stroke:
101.60 x 92.00 mm

Fuel System:
Sequential Fuel Injection

325 @ 5000 rpm (GMC Sierra Denali)
320 @ 5000 rpm (GMC Yukon Denali/Yukon XL Denali)
320 @ 5000 rpm (GMC Yukon XL and Chevrolet Suburban)
315 @ 5000 rpm (HUMMER H2)
300 @ 4400 rpm (2500 HD and 3500 GMC Sierra and Chevrolet Silverado equal to or greater than 8600 lbs. GVW)
290 @ 4400 rpm (Chevrolet Express and GMC Savana 3500 Series)

Torque (lb-ft):
370 @ 4000 rpm (GMC Sierra Denali)
365 @ 4000 rpm (GMC Yukon Denali/Yukon XL Denali)
360 @ 4000 rpm (GMC Yukon XL/Suburban)
360 @ 4000 rpm (HUMMER H2)
360 @ 4000 rpm (2500 HD and 3500 GMC Sierra and Chevrolet Silverado equal to or greater than 8600 lbs. gvw)
350 @ 4000 rpm (Chevrolet Express and GMC Savana 3500 Series)

Fuel Shut Off:
5600 rpm
6000 rpm (With M32 transmission)

Emissions Controls:
Evaporative System
Catalytic Converter
Exhaust Gas Recirculation (Chevrolet Express and GMC Savana)
Positive Crankcase Ventilation

GMC Sierra Denali (formerly Sierra C3)
GMC Yukon Denali
GMC Yukon XL Denali and Chevrolet Suburban
GMC Yukon XL 3500 Sierra and Chevrolet Silverado Pickup and Chassis Cab 2500 HD and 3500 GMC Sierra and Chevrolet Silverado
Chevrolet Express and GMC Savana

Cast Iron
Cylinder Head:
Cast Aluminum

Intake Manifold:

Exhaust Manifold:
High Silicon Molybdenum
Cast Nodular Iron

Main Bearing Caps:
Powder Metal
Cast Iron with Undercut and Rolled Fillets

Connecting Rods:
Forged Powder Metal

Additional Features:
Extended Life Spark Plugs
Extended Life Coolant
Oil Level Sensor
Electronic Throttle Control (All applications except Chevy Express and GMC Savana)
Electronic Throttle Control on H2, including specific off road (low range) throttle progression calibration

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