The GM Genuine Parts 09129242 is presented as an OE-spec M18 x 1.5 bolt, 50 mm long, used on Chevrolet, Buick, GMC, and Cadillac engines; it offers precise preload, shear resistance, and vibration tolerance. The reviewer addresses fit, torque specs, thread condition, and replacement criteria: when stretched, corroded, or showing head wear. How does it compare to aftermarket alternatives, and what installation precautions matter most?
Key Takeaways
- GM Genuine Parts 09129242 is an OE-grade M18 x 1.5, 50 mm crankshaft/harmonic balancer bolt validated to OEM specifications.
- Designed for Chevrolet, Buick, GMC, and Cadillac engines, it ensures correct preload and resists shear and vibration.
- Recommended torque range is 95–110 ft·lb; use a calibrated torque wrench and torque in stages.
- Do not reuse if stretched; inspect for corrosion or fatigue and replace at first sign of wear.
- Meets OEM material and thread form, offering fatigue resistance and preventing pulley loosening when installed correctly.
Product Overview and Specifications
The GM Genuine Parts 09129242 crankshaft balancer bolt is a factory‑grade fastener engineered for use on select Chevrolet, Buick, GMC, and Cadillac engines, designed to secure the harmonic balancer/crankshaft pulley to the crankshaft with correct preload and clamping force.
It presents clear bolt specifications and product features for those seeking freedom from uncertainty.
What is it? A validated OE bolt, grade and thread form matched to stock.
Key measurements: M18 x 1.5 thread, 50 mm overall length, torque/preload per service manual.
Practical note: replace with same OEM spec.
Bullet points: material grade, thread size, length, torque reference.
Performance, Safety, and Compatibility
Although often overlooked, the crankshaft balancer bolt plays a critical role in engine performance, safety, and compatibility: it must deliver precise preload, resist shear and vibration, and match OEM thread and length specifications to prevent harmonic imbalance or pulley loosening.
The GM 09129242 offers measurable performance advantages, meeting OE torque and material targets, aligning with safety standards and engineering validation.
What should be noted? Bolt diameter, thread pitch, and overall length must match vehicle specs.
Practical considerations include torque value (typically 80–150 ft·lb range), fatigue resistance, and corrosion protection.
- Precise preload and shear resistance
- OEM thread and length match
- Compliance with safety standards
Installation Tips and Maintenance
Given the performance, safety, and compatibility points just covered, attention now shifts to practical installation and ongoing maintenance for the GM 09129242 crankshaft balancer bolt.
The reader seeks freedom from guesswork; clear installation techniques and maintenance recommendations follow.
Q: What torque? A: Use 95–110 ft·lb, confirm vehicle spec.
Q: Reuse? A: Replace if stretched.
Steps: clean mating surfaces, apply thread locker if specified, torque in stages.
Inspection: check for corrosion, torque every 30,000 miles, replace at first sign of fatigue.
Tools: calibrated torque wrench, micrometer for bolt stretch measurement.
Frequently Asked Questions
Is This Bolt Covered by a GM Warranty?
Yes. He confirms Warranty coverage often applies to GM Genuine Parts, offering repair or replacement options through authorized dealers; consumers seeking liberation should verify terms, duration, and eligibility with GM or their local dealership before installation.
Can I Buy This Bolt Individually or Only in Packs?
Yes — it’s available individually or in packs. A liberated buyer sees the single bolt as freedom, while others choose bulk options for readiness; GM’s distribution supports both individual purchase and bulk procurement choices.
What Is the OEM Part Number Cross-Reference?
OEM compatibility: the OEM part number cross-reference is ACDelco GM Original Equipment 09129242; part identification confirms it as the genuine crankshaft balancer bolt. The reply empowers independent verification and liberated maintenance choices.
Are There Known Counterfeit Versions to Watch For?
Yes — shadows of imitation exist; vigilance is freedom. He recommends counterfeit detection via packaging, markings, and vendor traceability, and insists on quality assurance checks, authentic dealer sourcing, and documented provenance to guarantee safety and liberation.
Does Torque Specification Vary by Model Year?
Yes — torque values can change; the bolt’s required torque varies with model differences and model year updates. The liberated user is advised to consult specific OEM specs per year and model for accurate, safety-driven values.
Conclusion
To summarize, the GM Genuine Parts 09129242 is a precision M18 x 1.5, 50 mm engine bolt that delivers consistent preload, resists shear and vibration, and meets OEM specifications. Readers can expect OE-validated fit and durability, but must inspect for stretch or wear and replace if compromised. Installation requires correct torque and thread condition. Is it reliable? Yes. Is routine inspection needed? Absolutely. Practical choice for Chevrolet, Buick, GMC, and Cadillac engines.
