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ACDelco Copper Core Spark Plug: Reliable Performance & Efficient Operation

(888 reviews)
Part # FR5LS
1 year warranty
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Product Information

Product Details
Part No. FR5LS
Warranty Details (1 Year Warranty)
ACDelco GM Original Equipment Conventional Spark Plugs are designed, engineered, and tested to rigorous standards, and are backed by General Motors. These Conventional Spark Plugs are designed for reliability and efficient performance, and are a high quality replacement for many vehicles on the road today. Their high-quality copper cores and outstanding suppression characteristics deliver reliable performance. They are also available for Marine applications. These premium aftermarket replacement spark plugs are manufactured to meet your expectations for fit, form, and function. ACDelco GM Original Equipment parts are the true OE parts installed during the production of or validated by General Motors for GM vehicles. Some ACDelco GM Original Equipment parts may have formerly appeared as GM Genuine Parts (OE) or ACDelco Professional.

Product Features:
  • GM regularly updates production and service part designs to integrate new materials and technologies
  • High-Quality Copper Core: Designed with high-quality copper cores for reliable performance and efficient operation.
  • Nickel Center Electrode Tip: Features a nickel center electrode tip for enhanced durability and consistent performance.
  • Outstanding Suppression Characteristics: Engineered to deliver outstanding suppression characteristics, ensuring smooth engine operation.
  • OE Replacement: These spark plugs are true Original Equipment (OE) parts, validated by General Motors for GM vehicles, ensuring perfect fit, form, and function.
  • Versatile Applications: Providing a high-quality replacement for a wide range of vehicles.
Specifications
Center Electrode Core Material:
Copper

Center Electrode Tip Material:
Nickel

Ground Configuration:
Standard

Ground Electrode Quantity:
1

Ground Electrode Tip Design:
Standard

Height:
1.12 in

Hex Size:
16 mm

Insulator Height:
2.002 in

Length:
4.16 in

Manufacturer Heat Range:
5

Pre-Gap Size:
0.035 in

Reach:
0.75 in

Resistor Type:
Yes

Seat Type:
Gasket

Thread Diameter:
0.551 in

Weight:
.4 lb

Width:
3.59 in
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4.75 out of 5
888 Customer Reviews
96% of respondents would recommend this to a friend
Ratings Distribution
5 Stars
760
4 Stars
80
3 Stars
25
2 Stars
2
1 Star
21
Great Spark PlugsNot exact replacement but worked.I would recommend Advance autoparts for restoring your vehic
Replaced junk plugs someone else had installedI will buy this product again for my hot rod if neededWill buy again.Change your plugs!!!!!!I will buy this again
Pros
48
Improves Engine Efficiency
42
Easy To Install
38
Increases Power
37
Durable
10
Lightweight
Cons
6
none
1
Decreases Gas Mileage
1
Difficult To Install
1
No Improvement In Performance
1
None
Best Uses
52
Everyday Driving
42
Replacement
21
Restoration
9
Performance Driving
4
Racing
Car & Truck
1
Auto Enthusiast
1
Mechanic
1
Truck Enthusiast
Describe Yourself
32
Casual Driver
31
Auto Enthusiast
19
Mechanic
17
Truck Enthusiast
3
Competitive Driver
Most Liked Positive Review
worked great
I have a 2002 avalanche Z66 that I was apparently running the wrong plugs in even though ACDelco originally said were for my truck and in the middle of last year put out a notice that they put the wrong years in the catalog. Anyway I was running a rich condition and the plugs were fouled up so I didn't want to spend to much money on plugs right now so I ordered these as copper is the best metal as far as conductivity for vehicles but it also has the shortest life, usually only 10-20k. Anyway these worked great!! my idle smoothed out the response was better. Im sure the gas mileage will increase a little as well. if you looking for a cheaper plug to use in the meantime while you save $100 for the more expensive kind look no further. great plug for the 5.3L
Most Liked Negative Review
Web page has wrong description
R44LTSM, has a 0.045 gap. NOT 0.060 as listed on the web page. Verify the required spark plug gap before selecting this spark plug. If 0.060 is required R44LTSM6 is the correct spark plug. R44LTSM6 is the same plug as R44LTSM but has the 0.060 gap. 1-star to get peoples attention. hopefully read this and select the correct spark plug.
Reviewed by 888 Customers
original replacements
Staff Reviewer -
nothing fancy, just the original replacement for a gm vehicle. priced fairly...
Bottom Line Yes, I would recommend to a friend
My favorite spark plug
Staff Reviewer -
I have been driving GM vehicles for 43 years and always use AC spark plugs. I believe in using original equipment when possible and all my cars and trucks last more than 200,000 miles.
Bottom Line Yes, I would recommend to a friend
would buy it again
Staff Reviewer -
it improved the performance of my truck.it gave it alot more power.
Bottom Line Yes, I would recommend to a friend
just ok
They are over rated there just ok I prefer ngk v powers they run better and perform way nicer.
Bottom Line No, I would not recommend to a friend
The GM Standard!!!
Staff Reviewer -
Good Old fashion tune up!
Bottom Line Yes, I would recommend to a friend
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