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An oil leak around your engine’s front cover can lead to messy repairs, oil loss, and extra labor if you install the wrong replacement seal. The GM Genuine Parts 296-02 (12585673) Engine Front Cover Seal is an original equipment replacement designed for selected GM engines. Its main advantage is GM-validated fit, but compatibility and correct installation matter more than the brand name alone. This review covers its verified dimensions, construction, fitment, installation concerns, and overall value so you can decide whether it belongs in your repair.
Quick Verdict
Verdict: Recommended with fitment and installation caveats
Best For: Owners and repair shops replacing a worn front crankshaft seal on a GM engine that specifies part 12585673.
Bottom Line: This GM Genuine Parts seal offers the reassurance of OE specifications, confirmed dimensions, and manufacturer support. However, it will not fix leaks from unrelated gaskets or damaged sealing surfaces, and installing it correctly can require significant engine disassembly.
GM Genuine Parts 296-02: Key Specifications
The following details come from GM’s official parts catalog and the product listing. They replace the conflicting dimensions in earlier descriptions of this seal.
| Specification | Verified Detail |
|---|---|
| Brand | GM Genuine Parts / ACDelco |
| ACDelco Part Number | 296-02 |
| GM Part Number | 12585673 |
| Product Type | Engine front cover / front crankshaft seal |
| Outside Diameter | 2.82 inches (71.7 mm) |
| Inside Diameter | 2.13 inches (54.1 mm) |
| Thickness | 0.33 inches (8.46 mm) |
| Material | Rubber |
| Classification | Original Equipment (OE) |
| Package Quantity | 1 seal |
| Compatibility | Selected GM engines; confirm by VIN and engine application |
| Warranty | GM lists a 24-month, unlimited-mile limited parts warranty, subject to terms and eligibility |
| Amazon ASIN | B000C9MBX8 |
Specification source: GM Genuine Parts official product catalog. Always confirm current fitment information before ordering.
Key Takeaways
- Verified OE replacement: GM Genuine Parts 296-02 corresponds to GM part number 12585673.
- Confirmed dimensions: The seal measures 71.7 mm outside diameter, 54.1 mm inside diameter, and 8.46 mm thick.
- Rubber construction: Designed for engine sealing applications, with GM validation for intended vehicle applications.
- Vehicle-specific fit: The same GM model may use different seals across engines and model years.
- Installation matters: Incorrect depth, orientation, or damage to the sealing surface can cause another leak.
- Warranty support: GM publishes a limited parts warranty, but coverage conditions should be checked with the seller.
Product Overview and Specifications
What Is the GM Genuine Parts 296-02 Engine Front Cover Seal?
The GM Genuine Parts 296-02 is a replacement seal used at the front of compatible engines, where the crankshaft passes through the engine’s front cover. Its purpose is to help keep engine oil inside while allowing the crankshaft to rotate. It is a sealing component, not a complete front cover gasket set.
GM identifies the product under part number 12585673, while ACDelco uses 296-02. Both numbers help you confirm that a retailer is showing the intended item. The GM catalog classifies the seal as OE and identifies rubber as its sealing material.
Unlike a universal seal selected by approximate measurements, this part is intended for specific engine applications. That makes checking the original GM part number more useful than selecting a seal by diameter alone.
The main reason to choose GM Genuine Parts 296-02 is its OE application match, not an unverified claim of better leakage performance than every aftermarket alternative.
What Comes in the Package?
The manufacturer’s catalog and Amazon listing identify this as a single-seal product. Do not assume it includes a complete timing cover gasket, crankshaft pulley bolt, installation driver, or additional sealing hardware.
If your repair involves removing the entire front cover, check the service procedure for other one-time-use parts, gaskets, and sealants you may need. Ordering them together can prevent delays once the engine is apart.
Who Should Buy It?
Best For
- Owners whose GM service parts catalog specifies seal 12585673.
- Mechanics replacing a leaking or damaged front crankshaft seal during an engine repair.
- Buyers who prefer a GM OE replacement over choosing an aftermarket seal solely by size.
Skip If
- Your engine requires a different front crankshaft seal part number.
- Your oil leak comes from the cover gasket, oil pan, or another component.
- You need a complete front cover resealing kit rather than one seal.
Before You Buy: Do not order GM 296-02 based only on your vehicle’s make, model, or engine size. Confirm GM part number 12585673 against your VIN and engine configuration. Also identify the actual source of the oil leak before replacing the seal.
Fit, Quality, and Durability Assessment
OE Fit and Dimensional Accuracy
The strongest documented feature of the GM Genuine Parts 296-02 is its original equipment application. GM states that its OE parts are engineered and validated for specified GM vehicles. This is useful when the front cover bore, crankshaft sealing surface, and seal width must work together.
The published dimensions give you a practical way to check the part before installation:
- 71.7 mm outside diameter: Relevant to the seal’s fit in the front cover opening.
- 54.1 mm inside diameter: Relevant to the crankshaft sealing interface.
- 8.46 mm thickness: Helps identify the correct seal profile and installation requirements.
These measurements are identification details, not instructions to force the seal into any opening with similar dimensions. The housing design and required installation depth still need to match your specific engine.
Material and Build Quality
GM lists rubber as the sealing material. The product is designed to help prevent oil leaks in its approved application, and GM describes its Genuine Parts line as engineered and tested to manufacturer standards.
However, the published product details reviewed here do not establish a specific rubber compound, exact temperature operating range, or measured leakage rate. Those figures should not be treated as product specifications without supporting test documents.
For your repair, correct part selection and installation are more meaningful than an unsupported heat-resistance number. Even a properly manufactured seal can leak if its lip is damaged or the crankshaft surface is worn.
Expected Durability
A front crankshaft seal is intended for extended service, but its actual life depends on engine condition, installation, oil contamination, and operating conditions. No verified mileage guarantee was found for this specific seal.
You should not interpret GM’s warranty as a promise that the seal will last for a fixed number of miles. Instead, look for correct installation, a smooth sealing surface, and no signs of fresh oil after the repair.
How It Performs in Real Use
The following examples explain where this part can help. They are practical repair scenarios, not results from an independent road or laboratory test.
1. Replacing a Confirmed Front Crankshaft Oil Leak
If inspection confirms that oil is escaping around the front crankshaft seal, replacing the damaged seal with the correct GM part can address that leak path. The seal must be positioned correctly, and the crankshaft sealing surface must be suitable for reuse.
If the leak comes from a different component, installing GM 296-02 will not solve the problem. Oil can travel across engine surfaces, so the visible drip location may not identify its source.
2. During Front Cover or Timing-Related Service
When the front of your engine is already disassembled for another repair, access to the front crankshaft seal may be easier. If the existing seal must be removed or is damaged, a new replacement can help avoid repeating labor later.
Check whether the vehicle’s procedure calls for replacing associated fasteners, gaskets, or sealant. This single-seal listing should not be mistaken for a complete engine resealing package.
3. Repairing a Higher-Mileage Engine
On an older engine, a fresh seal may be only part of the repair. A groove or damaged area on the crankshaft sealing surface can affect how well the new seal works.
Before installation, the mechanic should inspect the contact surface and front cover bore. If either is damaged, further repair may be necessary to prevent another leak.
4. Checking the Repair After Installation
Once the engine has been reassembled according to its service instructions, inspect the front cover area for fresh oil. A follow-up inspection after normal driving can help reveal problems that were not visible immediately.
If leakage continues, confirm the source again rather than assuming another new seal will fix it. Installation damage, engine ventilation problems, and nearby gasket leaks can produce similar symptoms.
Installation Tips and Vehicle Compatibility
Which GM Vehicles May Use This Seal?
GM’s parts catalogs list part 12585673 across selected Chevrolet, GMC, Buick, and Cadillac applications. Examples include certain Chevrolet Avalanche and GMC Sierra vehicles, along with selected Buick LaCrosse applications.
However, a model appearing in a general parts catalog is not enough to establish that every engine or trim uses this seal. You should confirm fit through a VIN-based GM parts lookup or a dealer parts department.
When checking compatibility, use this process:
- Record your vehicle’s year, model, and engine configuration.
- Look up the front engine cover or crankshaft front seal in the GM parts catalog.
- Confirm that the required GM part number is 12585673.
- Check whether the number has been superseded and whether the replacement is approved for your application.
- Compare the new seal with the removed part before installation.
Pro Tip: Before removing the old seal, document its installed position and orientation. Use the vehicle’s official service procedure to confirm the required depth for the replacement. A photo can help you remember the original layout, but it should not replace GM’s installation specifications.
Installation Tools and Preparation
Installing a front crankshaft seal may involve more than pressing a new ring into place. On many engines, access requires removing the crankshaft pulley or harmonic balancer and possibly other front-engine components.
Depending on your vehicle’s procedure, the job may require a pulley removal tool, seal removal tool, suitable seal installer, and torque wrench. A dedicated installation tool can help keep the seal straight and reduce the risk of damage.
Before starting:
- Confirm that you have the correct replacement seal and service instructions.
- Allow the engine to cool and follow vehicle-specific safety procedures.
- Clean the surrounding area so dirt does not enter the seal opening.
- Inspect the crankshaft sealing surface and front cover bore.
- Review any instructions about seal lip lubrication, sealant, and installation depth.
Installation Reference Checklist
| Step | Requirement | Notes |
|---|---|---|
| Fitment | GM 12585673 | Confirm by VIN |
| Surface preparation | Clean, undamaged contact surfaces | Avoid scratches |
| Seal position | Engine-specific service specification | Do not guess the depth |
| Lubrication / sealant | Follow GM instructions | Do not apply products automatically |
| Fastener torque | Vehicle-specific service manual | No universal value applies |
| Final inspection | Check for fresh oil leaks | Reinspect after operation |
Important: The earlier 8–12 Nm bolt torque and 0.5–1.0 mm seal-depth figures are not verified specifications for this product. Follow the procedure for your exact engine rather than applying those values.
Material and Installation Safety
The GM Genuine Parts 296-02 uses a rubber sealing material, but correct handling is essential. A damaged seal lip can allow oil to escape even when the part number is correct.
Do not hammer directly on the sealing surface, scratch the crankshaft, or force the seal into an opening that does not match its application. Use the proper driver and the installation method specified in the GM service information.
Lubrication requirements can differ between seal designs. Some seal types require specific preparation or dry installation, so follow the instructions for this part rather than assuming every seal should be coated with oil or grease.
If you are unfamiliar with crankshaft pulley removal, engine timing-related work, or the necessary torque procedures, professional installation is a safer choice. Incorrect reassembly can create a more serious repair problem than the original leak.
Pros and Cons
Pros
- GM-validated OE replacement for specified engine applications.
- Published dimensions help confirm product identity.
- Rubber sealing construction intended for the application.
- Clear GM and ACDelco part numbers simplify parts lookup.
- Manufacturer-backed limited warranty, subject to applicable terms.
Cons
- Fits only specified applications, despite broad GM model listings.
- Sold as one seal, not a complete front cover repair kit.
- Installation can require special tools and substantial labor.
Is It Worth the Price?
The GM Genuine Parts 296-02 is worth considering when you want an OE replacement with a confirmed GM part number. Its value comes from manufacturer compatibility and specifications rather than extra features. It is best viewed as an OE-focused repair part, not automatically the lowest-cost choice.
Front crankshaft seal repairs can involve significant labor. If your vehicle requires substantial disassembly, choosing the correct part matters because a poor fit or failed installation could mean repeating the work. A lower-priced alternative may still be reasonable if it has a confirmed application match and suitable installation requirements.
Before buying, compare the current seller price, shipping terms, return policy, and warranty eligibility. This product offers the most value when the original seal is confirmed as the problem and GM 12585673 is the specified replacement.
How It Compares to Alternatives
The closest alternative is another properly cross-referenced front crankshaft seal. For example, National 100470 is listed as an aftermarket cross-reference for ACDelco 296-02 and GM 12585673. It uses a different stated sealing material, so its installation instructions should be checked separately. A seal with a different design may require different preparation even when it fits the same application.
You can also compare GM Genuine Parts 296-02 with a dealer-supplied GM 12585673 seal. These refer to the same OE part identity rather than two different performance upgrades. Before choosing any aftermarket replacement, confirm its exact application, seal design, and manufacturer guidance.
Frequently Asked Questions
What Vehicles Use GM Genuine Parts 296-02?
GM catalogs list the seal for selected Chevrolet, GMC, Buick, and Cadillac applications. Fit depends on the engine and vehicle configuration, so verify part 12585673 through a VIN-based lookup before ordering.
What Are the Exact Dimensions of GM 296-02?
GM specifies a 71.7 mm outside diameter, 54.1 mm inside diameter, and 8.46 mm thickness. These dimensions help identify the seal, but you must also confirm the correct part number for your engine.
Can This Seal Be Reused After Removal?
Replacing a removed front crankshaft seal is generally the safer repair choice, especially if it was pulled out or its sealing lip was disturbed. Use a new part that matches your application and follow the service procedure.
Does GM 296-02 Stop Every Front Engine Oil Leak?
No. It addresses the sealing point for which it is designed. Leaks from the front cover gasket, oil pan, or another nearby component need a different repair.
Are Specialized Tools Required for Installation?
They may be required, depending on your engine. Front pulley removal and correct seal placement often benefit from purpose-made tools. Consult the GM service manual before starting the repair.
Is This Seal Suitable for Modified or Performance Engines?
It is designed for its listed OE applications. If your engine has a modified crankshaft, front cover, or operating conditions outside the factory setup, confirm seal compatibility with your engine builder or parts specialist.
What Warranty Comes With GM Genuine Parts 296-02?
GM’s official catalog lists a 24-month, unlimited-mile limited parts warranty, with labor coverage under specified dealer-installation conditions. Coverage depends on the applicable warranty terms, purchase source, and eligibility, so check with your seller.
Where Can You Buy Authentic GM Genuine Parts 296-02?
You can look for part 296-02 or GM 12585673 through GM dealership parts departments, recognized parts sellers, or Amazon. Check the seller’s identity, product number, packaging, return policy, and warranty eligibility before purchasing.
The Bottom Line
The GM Genuine Parts 296-02 (12585673) Engine Front Cover Seal is a sensible OE replacement when your engine specifies this exact part and the front crankshaft seal is the confirmed source of leakage. Its verified specifications and manufacturer backing are strengths, but limited fitment and potentially difficult installation make it unsuitable as a guesswork repair. Choose it for a confirmed application, and use the proper service procedure to protect your repair.
Ready to Buy?
Confirm GM part 12585673 matches your engine, then check current seller details and price.
