SYS.OK|MANUAL.DB● LIVE
HOMESERVICE MANUALSCHEVROLET2025TRAILBLAZER ACTIV, FWDREPAIR AND DIAGNOSISEXTERNAL PAGESDIFFERENT VARIANT/TRIMSECTION 4 (ENGINE MECHANICAL - 1.2L (LBP) - SPECIFICATIONS)SPECIFICATIONSENGINE MECHANICAL SPECIFICATIONS
2025 Chevrolet Trailblazer ACTIV, FWD

Engine Mechanical Specifications

2025 Chevrolet Trailblazer ACTIV, FWDSECTION Engine Mechanical Specifications
WARNING: This page is about a different variant/trim than selected.
Application Specification
Metric Units English Units
General Data
  • Engine Type
 3-Cylinder Inline
  • Displacement
 1199 ccm 73.17 CID
  • RPO
 1.2L (LIH)
  • Valves
 12
  • Bore
 75 mm 2.953 in
  • Stroke
 90.496 mm 3.563 in
  • Compression Ratio
 10:1
  • Spark Plug Gap
 0.60 - 0.70 mm 0.024 - 0.028 in
  • Firing Order
 1 - 2 - 3
Lubrication System
  • Oil Pressure - @ 2000 RPM 80°C - 100°C
 160 kPa - 190 kPa 23.21 PSI - 27.56 PSI
  • Oil Pressure - @ 4000 RPM 80°C - 100°C
 320 kPa - 400 kPa 46.41 PSI - 58.02 PSI
Engine Block
  • Engine Block Height
 276.34 mm 10.88 in
  • Crankshaft Main Bearing Bore Diameter
 48.868 - 48.882 mm 1.9239 - 1.9245 in
  • Cylinder Bore Diameter
 74.992 - 75.008 mm 2.9524 - 2.9531 in
  • Cylinder Bore Out-of-Round - Maximum
 0.013 mm 0.0005 in
  • Cylinder Head Deck Surface Flatness - over 25 mm length
 0.025 mm 0.001 in
Crankshaft
  • Main Journal Diameter Crankshaft
 43.992 - 44.008 mm 1.732 - 1.7326 in
  • Connecting Rod Journal Diameter Crankshaft (Standard Size)
 43.992 - 44.008 mm 1.732 - 1.7326 in
  • Crankshaft Thrust Bearing Seat Width
 21.994 - 22.028 mm 0.8659 - 0.8672 in
  • Crankshaft Main Bearing Thickness - ID W
 2.422 - 2.428 mm 0.0954 - 0.0956 in
  • Crankshaft Main Bearing Thickness - ID X
 2.428 - 2.434 mm 0.0956 - 0.0958 in
  • Crankshaft Main Bearing Thickness - ID Z
 2.434 - 2.440 mm 0.0958 - 0.0961 in
  • Crankshaft Main Bearing Clearance
 0.017 - 0.046 mm 0.0007 - 0.0018 in
  • Crankshaft End Play
 0.150 - 0.382 mm 0.0059 - 0.015 in
Connecting Rod
  • Connecting Rod Length
 153.25 mm 6.033 in
  • Crankshaft Bearing Bore Diameter Connecting Rod
 47.186 - 47.202 mm 1.8577 - 1.8583 in
  • Pin Bore Diameter Connecting Rod
 19.007 - 19.015 mm 0.7483 - 0.7486 in
  • Connecting Rod Bearing Shell Thickness (Standard Size)
 1.578 - 1.584 mm 0.0621 - 0.0624 in
  • Clearance Connecting Rod Bearing
 0.010 - 0.054 mm 0.0004 - 0.0021 in
  • Clearance Piston Pin in Connecting Rod
 0.007 - 0.021 mm 0.0002 - 0.0008 in
Piston
  • Piston Pin Diameter
 18.994 - 19.000 mm 0.7478 - 0.748 in
  • Piston Pin Bore Diameter
 19.005 - 19.01 mm 0.7482 - 0.7484 in
  • Piston Skirt Diameter @ 22.8 mm (0.90 in) from bottom of skirt before coating
 74.938 - 74.952 mm 2.9503 - 2.9509 in
  • Piston Skirt Diameter @ 22.8 mm (0.90 in) from bottom of skirt after coating
 74.958 - 74.992 mm 2.9511 - 2.9524 in
  • Piston Diameter @ 22.8 mm (0.90 in) from bottom of skirt
 74.857 - 74.889 mm 2.9471 - 2.9484 in
  • Piston Diameter @ 41.1 mm (1.62 in) from bottom of skirt
 74.06 - 74.098 mm 2.9157 - 2.9172 in
  • Piston Groove Width Upper Piston Compression Ring
 1.225 - 1.245 mm 0.0482 - 0.0490 in
  • Piston Groove Width Lower Piston Compression Ring
 1.22 - 1.24 mm 0.048 - 0.0488 in
  • Piston Groove Width Piston Oil Ring
 2.03 - 2.05 mm 0.0799 - 0.0807 in
  • Compression Height
 26.55 - 26.65 mm 1.0452 - 1.0492 in
  • Clearance Piston Pin Piston
 0.005 -0.016 mm 0.0002 - 0.0006 in
Piston Compression Rings and Oil Ring
  • Upper Piston Compression Ring Thickness
 1.170 - 1.190 mm 0.0461 - 0.0469 in
  • Lower Piston Compression Ring Thickness
 1.170 - 1.190 mm 0.0461 - 0.0469 in
  • Piston Oil Ring Rail Thickness
 1.09 - 1.15 mm 0.0429 - 0.0453 in
  • Piston Oil Ring Spacer Thickness
 0.387 - 0.42 mm 0.0152 - 0.0165 in
  • Upper Piston Compression Ring Gap
 0.18 - 0.33 mm 0.0071 - 0.013 in
  • Lower Piston Compression Ring Gap
 0.4 -0.6 mm 0.0157 - 0.0236 in
  • Piston Oil Ring Gap
 0.2 - 0.9 mm 0.0079 - 0.0354 in
Cylinder Head
  • Surface Flatness - Block Deck - in 25 mm
 0.025 mm 0.001 in
If the deck surface is out of specification, replace the cylinder head. Do not machine the cylinder head.
  • Surface Flatness - Block Deck - in 150 mm
 0.05 mm 0.002 in
If the deck surface is out of specification, replace the cylinder head. Do not machine the cylinder head.
  • Surface Flatness - Block Deck - between bolts
 0.03 mm 0.0012 in
If the deck surface is out of specification, replace the cylinder head. Do not machine the cylinder head.
  • Surface Flatness - Block Deck - overall
 0.1 mm 0.0039 in
If the deck surface is out of specification, replace the cylinder head. Do not machine the cylinder head.
  • Camshaft Bearing Bore - Front
 27.00 - 27.02 mm 1.063 - 1.0638 in
  • Camshaft Bearing Bore - Intermediate and Rear
 24.00 - 24.02 mm 0.9449 - 0.9457 in
  • Valve Seat Width - Intake
 1.0 - 1.4 mm 0.0394 - 0.0551 in
  • Valve Seat Width - Exhaust
 1.55 - 1.95 mm 0.061 - 0.0768 in
  • Valve Seat Angle
 90 degrees (+/-1 degrees)
  • Intake Valve Seat Angle Adjustment - Upper
 56 degrees (+/-4 degrees)
  • Exhaust Valve Seat Angle Adjustment - Upper
 50 degrees (+/-4 degrees)
  • Intake and Exhaust Valve Seat Angle Adjustment - Lower
 120 degrees (+/-4 degrees)
  • Valve Guide Bore
 5.00 - 5.02 mm 0.1969 - 0.1976 in
  • Intake Valve Guide Assembly Height
 12.25 - 12.75 mm 0.4823 - 0.502 in
  • Exhaust Valve Guide Assembly Height
 8.25 - 8.75 mm 0.3248 - 0.3445 in
  • Intake Valve Guide Length
 36.7 - 37.3 mm 1.4449 - 1.4685 in
  • Exhaust Valve Guide Length
 36.7 - 37.3 mm 1.4449 - 1.4685 in
Valve System
  • Intake Valve Disk Diameter
 27.9 - 28.1 mm 1.0984 - 1.1063 in
  • Exhaust Valve Disk Diameter
 23.17 - 23.43 mm 0.9122 - 0.9224 in
  • Intake Valve Stem Diameter
 4.955 - 4.975 mm 0.1951 - 0.1959 in
  • Exhaust Valve Stem Diameter
 4.945 - 4.965 mm 0.1947 - 0.1955 in
  • Intake Valve Length
 97.60 - 97.86 mm 3.8426 - 3.8527 in
  • Exhaust Valve Length
 96.60 - 96.86 mm 3.8031 - 3.8134 in
  • Intake and Exhaust Valve Spring Length - Unstressed
 41.8 - 44.8 mm 1.6457 - 1.7638 in
  • Intake Valve Spring Length - 162 N +/-10 (Valve Closed)
 34.8 mm 1.3701 in
  • Exhaust Valve Spring Length - 235 N +/-10 (Valve Closed)
 31 mm 1.2205 in
  • Intake Valve Spring Length - 338 N +/-20 (Valve Open)
 25.8 mm 1.0158 in
  • Exhaust Valve Spring Length - 420 N +/-20 (Valve Open)
 22 mm 0.8661 in
Camshaft
  • Camshaft Bearing Diameter - Front
 26.935 - 26.960 mm 1.0604 - 1.0614 in
  • Camshaft Bearing Diameter - Intermediate and Rear
 23.935 - 23.960 mm 0.9423 - 0.9433 in
  • Camshaft Bearing Clearance
 0.040 - 0.085 mm 0.0016 - 0.0033 in
  • Camshaft Thrust Width
 27.128 - 27.178 mm 1.0680 - 1.07 in
  • Camshaft Thrust Width - Cylinder Head
 26.853 mm 1.0572 in
  • Camshaft End Play
 0.275 - 0.325 mm 0.0108 - 0.0128 in
RENDER: 1.0x

NO RELATED

Recommended Tools & Savings

Use the Manual With the Right Hardware

Pair factory procedures with proven DIY tools so the instructions are easier to execute.

Affiliate disclosure: We may earn a commission at no extra cost to you.

Shop Manual-Ready ToolsFree Quote CheckQuote Shield Pro

When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • • You smell fuel, burning insulation, or see smoke.
  • • Brakes feel soft, pull hard to one side, or make grinding noises.
  • • The engine overheats, stalls repeatedly, or misfires under load.
  • • You are missing required tools, torque specs, or safe lifting equipment.
  • • You are not confident in the next step or safety outcome.