GM 391423 Dynamic Jetstar Nos Grille Lower Extension Lh

( Brand: Gm ), ( Manufacturer Part Number: 391423 ), ( Part Type: Grille ), ( Manufacturer Warranty: No ), ( Finish: Stamped Steel ), ( Placement On Vehicle: Front, Left ), ( Country Of Origin: United States )

Review GM Oldsmobile Dynamic Jetstar Nos Grille Lower Extension Lh fits 1966–1998

The **GM 391423 1966 Oldsmobile Dynamic Jetstar 98 NOS Grille Lower Extension (LH)** is a meticulously crafted, high-quality reproduction part designed to restore the iconic front-end character of one of General Motors most distinctive muscle cars from the mid-1960s. This left-hand side (LH) grille lower extension, numbered **391423**, is a faithful replication of the original component found on the legendary **1966 Oldsmobile Dynamic Jetstar 98**, a model celebrated for its aggressive styling, powerful performance, and timeless appeal. Crafted from durable, corrosion-resistant materials, this part ensures both authenticity and longevity, allowing restorers and enthusiasts to achieve a flawless, factory-accurate appearance. The Jetstar 98 s front end was a standout feature, blending sharp, angular lines with a bold, dual-slotted grille that exuded confidence and speed qualities perfectly preserved in this NOS (New Old Stock) extension. Whether installed on a fully restored classic or a project car in the early stages of assembly, this grille lower extension enhances the vehicle s visual impact, complementing the iconic chrome grille and hood scoop that define the Jetstar 98 s aggressive stance. Ideal for collectors, show car builders, and performance-minded drivers who demand precision and heritage, this part bridges the gap between originality and modern craftsmanship, ensuring that every detail aligns with the original 1966 specification. With its clean, unaltered condition and exacting fitment, the **GM 391423** is an essential addition for anyone seeking to bring the unmistakable allure of the Dynamic Jetstar 98 to life.

### **Pros and Cons of Buying a 1966 Oldsmobile Dynamic Jetstar (GM 391423, 98 NOS Grille, Lower Extension, LH)**

#### **Pros**

1. **Classic American Muscle Car Heritage** The 1966 Oldsmobile Dynamic Jetstar is a well-regarded model from the golden era of American muscle cars, known for its distinctive styling, performance, and engineering. It represents a piece of automotive history that enthusiasts value.

2. **Strong Engine Options** The Jetstar was available with a variety of powerful engines, including the **390 CID V8 (325 360 hp)** and the **425 CID Rocket V8 (360 375 hp)**. These engines were robust for their time and can be restored or modified for better performance.

3. **Distinctive Styling** The Jetstar s **98 NOS grille, lower extension, and unique body styling** make it stand out from other mid-60s Oldsmobiles. Its aggressive, futuristic look was ahead of its time and remains desirable among collectors.

4. **Potential for Restoration** If the car is in rough condition, a well-executed restoration could yield a highly collectible and valuable vehicle. The Jetstar is not as common as some other Oldsmobiles, which could make it more sought after in the future.

5. **Parts Availability** While parts for classic Oldsmobiles can be challenging to find, the Jetstar s popularity means that some key components (engines, transmissions, body panels) may still be accessible through specialty suppliers or restoration shops.

6. **Driving Experience** For those who appreciate the feel of a mid-60s muscle car, the Jetstar offers a mix of power and handling that can be enjoyable, especially if the suspension and steering are restored to proper condition.

7. **Potential for Investment** If the market for classic muscle cars continues to rise, a well-preserved Jetstar could appreciate in value over time. However, this is speculative and depends on future trends.

---

#### **Cons**

1. **High Maintenance and Restoration Costs** A 1966 Oldsmobile, especially one with **98 NOS grille and lower extension modifications**, is likely to require extensive work. Rust, worn-out suspension, failing electrical systems, and outdated fuel/ignition components are common issues. Restoration costs can easily exceed **$10,000 $30,000 **, depending on the car s condition.

2. **Rust and Structural Issues** Many cars from this era suffer from rust, particularly in the floor pans, rocker panels, and frame rails. A thorough inspection (or a **frame-off rust inspection**) is essential before purchasing.

3. **Engine and Transmission Wear** The **390 or 425 V8 engines** from this era were durable but have likely accumulated significant mileage. Common problems include **valve train wear, oil leaks, rod bearing failure, and transmission synchro issues**. Rebuilding or replacing these components can be expensive.

4. **Electrical and Modernization Challenges** Classic cars often have **outdated wiring, vacuum systems, and mechanical fuel injection (if equipped)**. Modernizing these systems for safety and reliability (e.g., adding a modern ignition system, fuel pump, or alternator) is necessary for safe daily driving but adds to costs.

5. **Limited Daily Usability** Even after restoration, a Jetstar may not be practical for daily use due to **poor fuel economy, limited modern amenities (no power steering, power brakes, or modern climate control), and high insurance costs** for a classic car.

6. **Market Saturation and Competition** The classic car market is crowded, and while the Jetstar is desirable, it competes with other **Chevelles, Camaros, and even Pontiac GTOs** for collector interest. Selling it later may not be as straightforward as buying.

7. **Hidden Modifications and Alterations** The **98 NOS grille and lower extension** suggest that the car may have had **aftermarket modifications**, which could affect its originality and value. Some owners add unnecessary weight or performance parts that reduce drivability or reliability.

8. **Insurance and Storage Costs** Classic car insurance can be **expensive** (often **$1,000 $3,000 per year** for a high-value restoration project). Secure storage (garage or climate-controlled facility) is also a significant ongoing cost.

9. **Time-Consuming Project** Restoring a Jetstar to concours-level condition is a **multi-year project** that requires mechanical skill, patience, and access to specialized tools. Many enthusiasts underestimate the time and effort required.

10. **Depreciation Risk** Unlike modern cars, classic cars can **lose value if not maintained properly**. A poorly restored or neglected Jetstar will not hold its value, and the market for them is not as stable as newer vehicles.

---

### **Conclusion**

Buying a **1966 Oldsmobile Dynamic Jetstar (GM 391423, 98 NOS grille, lower extension)** is a **passionate project** rather than a practical purchase. It is best suited for **enthusiasts with mechanical skills, deep pockets, and a long-term commitment** to restoration. The car offers **historical significance, strong engine potential, and a unique aesthetic**, but it comes with **high costs, maintenance challenges, and practical limitations**.

If you are **not prepared for a major restoration project** or **do not have the time/money to invest**, this purchase may not be the right choice. However, if you **love classic muscle cars, enjoy hands-on projects, and are willing to commit years to bringing it back to life**, the Jetstar can be an incredibly rewarding and valuable addition to your collection.

---

### **Recommendation**

- **Get a professional inspection** (preferably a **frame-off rust inspection**) before purchasing.

- **Verify the engine and transmission condition** consider having a mechanic pull the engine and transmission for evaluation.

- **Check for originality** ensure the **98 NOS grille and lower extension** are authentic and not aftermarket additions that devalue the car.

- **Budget for a full restoration** expect to spend **$20,000 $50,000 ** depending on the car s condition.

- **Store it properly** rust prevention and climate control are critical for long-term preservation.

- Consider **buying a more restored or lower-mileage example** (if available) to reduce risk.

- Look into **alternative classic cars** that may be **more practical or less expensive to restore** (e.g., a **1965 Cutlass, 1967 Chevelle, or 1964 Pontiac GTO**).

- If you want a **drivable classic**, consider a **well-maintained 1960s Olds 442 or a restored Camaro SS** that requires less work.

- Start with a **simpler project car** (e.g., a **1960s Ford or Chevy**) to gain experience before tackling a Jetstar.

- Join **classic car forums (like Hemmings, MuscleCarForum, or Oldsmobile forums)** to learn from experienced restorers.

**Final Verdict:** The **1966 Oldsmobile Dynamic Jetstar is a fantastic car for the right buyer** one who is **passionate, patient, and financially prepared** for a long-term restoration. For everyone else, it may be a **costly hobby** rather than a wise investment.

Details:

1966 Oldsmobile Dynamic 88 Jetstar 98 NOS grille lower extension LH 391423: genuine GM extension, drivers side, part number 391423.This fits 88, Delta Star fire. Brand new, still has original parts tag attached, never installed.

part #: 391423 prices

• $24.99-$65.00

specifications grilexte:

• for makes: Oldsmobile
• for years: 1966-1998
• brand: Gm
• mpn: 391423
• part type: Grille
• manufacturer warranty: No
• finish: Stamped Steel
• placement on vehicle: Front, Left
• country of origin: United States

offer grilexte:

• sold: 0
• options: Ship-to-home
• quantity: 1
• started: May 31, 2026
• availability: In Stock

seller grilexte:

• rating: 100.0%
• # reviews: 19244
• city: Toledo, Ohio

payments grilexte:

• other
• credit card: Discover
• wallet: Apple-pay

returns grilexte:

• policy: No Returns

shipping grilexte:

• service: USPS Priority Mail, UPS Ground, FedEx Ground / FedEx Home Delivery
• carrier: USPS, UPS, FedEx
• type: Calculated
• transit: 8-13 Days
• cost: $19.85
• class: Expedited, Standard

general grilexte:

• condition: Used
• Car Truck Parts Accessories > Exterior Parts Accessories > Grilles

Gm 391423 Is Similar To:

• ------- Gm Oldsmobile Cutlass Exterior Oem Grille Olds (40.9% similar) The grille itself is in very good condition with no cracks and all mounting tabs are intact oldsmobile cutlass 442 F85 exterior olds Gm. This grille was pulled from a 1971 cutlass. The chrome oldsmobile badge is in very good condition. The chrome mouldings that go along sages has some slight bends...(March 1st, 2018)
• 2 3664899 Chevrolet Lot Of Gm Grill Grille Crank Hole Cover Chevy (25.2% similar) See pics for condition. Lot of 2 Gm grill crank hole covers, part number I am not familiar with all makes and model's this fits, please verify pics match your application. Pieces are in good used shape...(January 8th, 2019)
• 25528715 Lh 25528716 Rh General Motors Oldsmobile Cutlass Supreme Euro Nos Gm (32.3% similar) Part is stamped on each. Discontinued from Gm pair of left side and right head light bezels, grille surrounds for a 1987 , 1988 oldsmobile cutlass, 442, supreme, euro car...(September 30th, 2018)
• 3942145 Nos Chevrolet Gm Cxhevrolet Impala Bel Air Biscayne Radiator Support (27.3% similar) There is surface rust on the lower side. This is a nos part but it was not stored properly. Please look at the pictures closely to determine condition...(March 21st, 2018)
• 00000000 Buick Gsx Rear Spoiler New Nos Genuine Gm (29.9% similar) Buick nos GSX spoiler. It has not been mounted. Original box pictured. I bought this from Buick many years ago. It has the original black primer from Gm...(October 9th, 2018)
• 03875746 Gm Nos Chevrolet Corvette (32.4% similar) Any questions call Les. Advertised locally reserve right to end listing early...(June 12th, 2017)
• 03929895 Gm Chevrolet Impala Or Passenger Car Front Upper Grille Oem (29% similar) This is a used oem part removed from 1969 Chevrolet impala. The compatibility tool may not be completely accurate for this part...(May 3rd, 2018)
• 10000180 Gm Nos 1980s Pontiac (18.9% similar) Up for offer is an nos 1980 S Pontiac's header panel emblem. The part number is group item in good unused nos condition and comes its original Gm parts box. It was well stored and looks good...(October 17th, 2017)
• 10002936 General Motors Pontiac Phoenix Front Grille Nos Gm (33.8% similar) ...(May 3rd, 2018)
• 10007760 Gm Nos 1978 1979 (15.7% similar) Flat rate shipping cost is to the lower 48 states of USA only. This an original nos Gm part. When they are gone forever. You are viewing a listing for nos Gm Pontiac grand am lh grille new old stock original discontinued part...(May 22nd, 2017)
• 10013168 Gm Original Oem Right Lower Radiator Grille Grand Prix (34.3% similar) Very heavy in the 1950S and a few 1970 S. All American made cars 1930S 1940S 1950S 1960 S. Or if you choose to re-purpose, display in your man cave, hot rod, rat rod. Items are perfect to be re-chromed for show room quality. Some have dings and slight damage. From none to light heavy pitting no ...(July 12th, 2018)