The firing order for GM's 6.0 L V8 engines is 1-8-7-2-6-5-4-3.
GM’s 6.0 L V8 family, part of the Gen IV LS lineup (including engines such as LQ4, LQ9, L76, and L96 variants), uses a consistent firing sequence to coordinate spark timing and valve operation. The cylinder numbering convention for LS engines places Bank 1 on one side with cylinders 1, 3, 5, and 7, and Bank 2 on the opposite side with cylinders 2, 4, 6, and 8; front-most cylinders are 1 and 2.
Firing order sequence
The following list shows the standard firing order in the exact sequence in which cylinders fire on most GM 6.0 L V8 engines.
- Cylinder 1 fires first
- Cylinder 8 fires second
- Cylinder 7 fires third
- Cylinder 2 fires fourth
- Cylinder 6 fires fifth
- Cylinder 5 fires sixth
- Cylinder 4 fires seventh
- Cylinder 3 fires eighth
Note: The numbers refer to the standard LS engine cylinder numbering. This sequence is widely used across Gen IV 6.0 L engines, but always verify with the specific vehicle’s service manual or timing chain cover markings if you're diagnosing ignition or timing issues.
Cylinder numbering and banks
For reference, on LS-family engines: Bank 1 comprises cylinders 1, 3, 5, and 7, while Bank 2 comprises cylinders 2, 4, 6, and 8. Front-most cylinders are 1 (Bank 1) and 2 (Bank 2). This numbering helps you map the firing order to the physical layout when inspecting spark plugs, wires, or coils.
Maintenance and practical notes
When replacing spark plugs, ignition coils, or wires, ensure you follow the firing order precisely to avoid misfires or timing issues. Use OEM-recommended parts and correct torque specifications. If a misfire is suspected, verify each coil pack and spark plug against the factory firing sequence and check for damaged wires or incorrect wiring.
Summary
The GM 6.0 L V8 (Gen IV LS family) uses a firing order of 1-8-7-2-6-5-4-3, with Bank 1 carrying cylinders 1, 3, 5, 7 and Bank 2 carrying 2, 4, 6, 8. This sequence is standard across most 6.0 L variants (LQ4/LQ9/L76/L96, etc.) and is essential for proper ignition timing and smooth engine operation. Always consult the specific service manual for your exact engine variant to confirm any variant-specific differences.
What side is odd and even on LS?
Cylinder Arrangement: As with earlier V8s, the LS engines have cylinders numbered with odd numbers on the left and even numbers on the right.
Is a 6.0 a 400?
Understanding the 6.0 Liter Engine Size and Comparisons
A 6.0 liter engine refers to its displacement, approximately 366 cubic inches, larger than a 350 (5.7L) or 400 (6.6L) motor.
What happens if you get the firing order wrong?
Symptoms of an incorrect firing order include:
Engine turns over but won't start. Rough running or loud misfires. Loss of power or stalling.
Why did LS change firing order?
GM adopted a special firing order in its LS engine series (Gen 3 and 4), which feature a 4/7 and 2/3 swap for the same reasons…to smooth out the harmonics in the pursuit of greater engine durability and to potentially generate more power.