Iridium IX Spark Plug (TR55IX)
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Iridium IX Spark Plug (TR55IX)
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NGK Iridium IX Spark Plug (TR55IX)

Part No. 7164 Warranty Details  

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Laser-welded iridium center electrode is resistant to heat, corrosion and electrical wear. The tapered ground electrode minimizes quenching. Provides outstanding acceleration, high fuel efficiency and durability.

Product Features:
  • 0.6 mm iridium-tip center electrode provides durability and a high melting point
  • Taper-cut ground electrode shape provides improved flame reproduction
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Electrode Core Material:Iridium
Electrode Tip Material:Iridium
Ground Strap Quantity:1
Manufacturer Heat Range:5
Resistor:Yes
Shorty Spark Plug:No
Spark Plug Reach:0.708 in
Spark Plug Seat Type:tapered
Spark Plug Thread Size:14 mm
Tip Configuration:Loose
Type:Iridium IX
Wrench Diameter:5/8 in

REVIEW SNAPSHOT®

by PowerReviews
NGKIridium IX Spark Plug (TR55IX)
 
4.7

(based on 35 reviews)

Ratings Distribution

  • 5 Stars

     

    (28)

  • 4 Stars

     

    (5)

  • 3 Stars

     

    (1)

  • 2 Stars

     

    (0)

  • 1 Stars

     

    (1)

94%

of respondents would recommend this to a friend.

Pros

  • Improves engine efficiency (27)
  • Increases power (21)
  • Easy to install (20)
  • Durable (13)
  • Lightweight (6)

Cons

  • No improvement in performance (3)

Best Uses

  • Everyday driving (28)
  • Replacement (19)
  • Performance driving (17)
  • Restoration (7)
  • Racing (6)
    • Car & Truck:
    • Casual driver (6), Auto enthusiast (4)
    • Reviewer Profile:
    • Casual driver (11), Auto enthusiast (9), Mechanic (5), Truck enthusiast (5)

Most Liked Positive Review

 

Will buy again.

I put these in my 2001 Cadillac Seville SLS. I was having intermittent missing and occasional starting problems - especially when hot. Since I bought the car used and didn't know the service...Read complete review

I put these in my 2001 Cadillac Seville SLS. I was having intermittent missing and occasional starting problems - especially when hot. Since I bought the car used and didn't know the service history, I decided to replace the plugs first. This solved the problem instantly. Even though pre-gapped, you should check the gap, as 3 out of 8 were off. No noticeable fuel economy improvement, however, above problems were solved and there IS a noticeable power increase - probably in the 10% range.

VS

Most Liked Negative Review

 

fragile

These plugs are fragile, must be very careful gaping them, I cracked one installing it on the back side of engine and I have never broken a plug in my life, did not...Read complete review

These plugs are fragile, must be very careful gaping them, I cracked one installing it on the back side of engine and I have never broken a plug in my life, did not do anything extra for motor runs normal,took out old e-3s and if I had to do over I would go with the e-3s or ac-delco. Overall just a normal replacement plug that is a little on the delicate side!

Reviewed by 35 customers

Displaying reviews 1-10

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5.0

Great

By 

from New port Richey , florida

Verified Buyer

Comments about NGK Iridium IX Spark Plug (TR55IX):

Easy to use
Durable
Are a bit pricey

Comment on this reviewHelp Icon(earn points)

 
5.0

A distance driver's perfect gift!

By 

from Weslaco,TX

Pros

  • Increase Gas Mileage

Cons

    Best Uses

      Comments about NGK Iridium IX Spark Plug (TR55IX):

      Installed these on a bone-stock 1996 Mustang GT after the Bosch Iridiums consumed 7 1/2 gallons of gas with just 130 miles of driving.

      Not even after 5 seconds of starting the Mustang, high idle quickly adjusted to normal. A bit of city driving showed these NGK Iridium's can handle stop-and-go traffic without hesitation/lag and no massive gulp of fuel.

      Now for the fun part: I reset my tripmeter and went on a long distance highway cruise without stopping to refuel or for a traffic light (merry-go-round cruising). With 3.925 gallons (1 Quart on the Mustang fuel gauge) I topped 138.5 miles...so that's 35.28 miles per gallon. Perfect for a distance driver!

      Comment on this reviewHelp Icon(earn points)

       
      4.0

      Worth the money

      By 

      from Austin, TX.

      About Me Do It Yourselfer

      Pros

      • Improves Engine Efficiency
      • Increases Power

      Cons

      • None

      Best Uses

      • Performance Improvement

      Comments about NGK Iridium IX Spark Plug (TR55IX):

      Fit my 99 Suburban perfectly. Was having some trouble firing up in the cool morning. these new plugs along with AC Delco wires fixed the problem and have seen about a 10% improvement in performance especially when merging into traffic. She just has a little more pep in her step.

      Comment on this reviewHelp Icon(earn points)

       
      5.0

      Works for my '96 Roadmaster

      By 

      from Miami, FL

      About Me Auto Enthusiast

      3 or more reviews submitted

      Pros

      • Durable

      Cons

        Best Uses

          Comments about NGK Iridium IX Spark Plug (TR55IX):

          Great product. Put it on my 1996 Buick Roadmaster. Have had it on for 4 months now. To be honest, I have not noticed an increase in performance or gas mileage though. Good thing though is that these are supposed to last a lot longer, therefore, less labor.

          Comment on this reviewHelp Icon(earn points)

          (7 of 11 customers found this review helpful)

           
          5.0

          Iridium IX Spark Plug (TR55IX)

          By 

          from Chicago, Il.

          About Me Auto Enthusiast, Casual Driver

          Verified Buyer
          Helpful Reviewer

          Pros

          • Durable
          • Easy To Install
          • Improves Engine Efficiency

          Cons

            Best Uses

            • Everyday Driving
            • Performance Driving
            • Replacement

            Comments about NGK Iridium IX Spark Plug (TR55IX):

            Love the Plugs. I have these Plugs in both my Vehicles, 02 Ford Escape/07 Chevy Cobalt, and I am very satisfied with the overall performance of this product.

            Comment on this reviewHelp Icon(earn points)

            (7 of 12 customers found this review helpful)

             
            4.0

            gets the job done

            By 

            from East Haddam ct

            About Me Truck Enthusiast

            Verified Buyer
            Helpful Reviewer

            Pros

              Cons

                Best Uses

                • Everyday Driving
                • Replacement

                Comments about NGK Iridium IX Spark Plug (TR55IX):

                Like I said gets the job done, didn't notice the power increase others mentioned but certainly didn't hurt it either

                Comment on this reviewHelp Icon(earn points)

                (5 of 9 customers found this review helpful)

                 
                5.0

                Great plugs, just as described

                By 

                from Wilson, NC

                About Me Casual Driver

                Verified Buyer
                Helpful Reviewer

                Pros

                • Improves Engine Efficiency
                • Increases Power

                Cons

                  Best Uses

                  • Everyday Driving
                  • Performance Driving
                  • Replacement

                  Comments about NGK Iridium IX Spark Plug (TR55IX):

                  Tell the difference as soon as I had them put in. Car started right up everytime (before my start-up was kinda sometimey). Seems like they will be long lasting but haven't driven long enough yet.

                  Comment on this reviewHelp Icon(earn points)

                  (10 of 13 customers found this review helpful)

                   
                  5.0

                  Burning rubber

                  Pros

                  • Easy To Install
                  • Improves Engine Efficiency
                  • Increases Power

                  Cons

                    Best Uses

                    • Everyday Driving
                    • Performance Driving
                    • Replacement

                    Comments about NGK Iridium IX Spark Plug (TR55IX):

                    I did through research on these before I bought them. Both on this website and others.
                    There is no need to buy thread lube. Unless the vehicle is vintage. My ASE certified mechanic set me straight on that.
                    There is no need to gap either. They install like, well spark plugs.
                    I noticed a substantial power increase. My car downshifts less, and upshifts sooner. I can get the car to break traction more often than I used to.
                    I keep close track of the fuel economy. I have noticed a 1 to 2 MPG increase.

                    Comment on this reviewHelp Icon(earn points)

                    (5 of 10 customers found this review helpful)

                     
                    5.0

                    Quality plug

                    By 

                    from Hemet, Ca

                    About Me Casual Driver

                    Verified Buyer
                    3 or more reviews submitted

                    Pros

                    • Durable
                    • Easy To Install
                    • Improves Engine Efficiency
                    • Increases Power
                    • Lightweight

                    Cons

                      Best Uses

                      • Everyday Driving
                      • Performance Driving
                      • Racing
                      • Replacement
                      • Restoration

                      Comments about NGK Iridium IX Spark Plug (TR55IX):

                      Awesome product

                      Comment on this reviewHelp Icon(earn points)

                      (6 of 11 customers found this review helpful)

                       
                      5.0

                      Good Premium Plugs

                      By 

                      from Austin TX

                      About Me Mechanic

                      Ask me a question

                      Verified Buyer
                      Level 4

                      Pros

                      • Durable
                      • Improves Engine Efficiency
                      • Increases Power

                      Cons

                        Best Uses

                        • Everyday Driving
                        • Performance Driving

                        Comments about NGK Iridium IX Spark Plug (TR55IX):

                        I always run NGK plugs in every gas engine I own. They have always worked great for me. The iridium plugs with their increased life are worth the extra cost especially if they are hard to change.

                        Comment on this reviewHelp Icon(earn points)

                        Displaying reviews 1-10

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                        Do you have questions about this product?(earn points for answers!)

                         

                        Ask a question, get answers from real customers and in-house experts. For further assistance, please review your support options on our Contact Us page.

                        10 Questions | 11 Answers
                        Displaying questions 1-10
                        • Q:

                          will these work for a toyota corolla 2008
                          Asked on 8/27/2014 by sunny from texas

                          1 answer

                          • CUSTOMER CARE

                            A:

                            Hi Sunny, glad to assist you! This part is not an exact fit for your 2008 Toyota Corolla. We do have an exact fit part available online for your vehicle and the part number is 5464. Please enter your vehicle on our website and search for this part to check the fitment.

                            Answered on 8/28/2014 by Steve from AAP
                        • Q:

                          Are these spark plugs high performance?
                          Asked on 3/18/2014 by Kroydog

                          1 answer

                          • CUSTOMER CARE

                            A:

                            It's a good question, Kroydog! This plug line (IX) is an entry performance line.

                            Answered on 3/19/2014 by Vincent from AAP
                        • Q:

                          What is the gap for 2000 GMC k2500 454 big block?
                          Asked on 11/1/2013 by Northgregg

                          2 answers

                          • CUSTOMER CARE

                            A:

                            Hi Northgregg, this NGK Iridium IX Spark Plug (TR55IX) -part# 7164 is an exact fit for your 2000 GMC K2500 and is pre-gapped at 0.060".

                            Answered on 11/3/2013 by Vincent from AAP
                          • CUSTOMER CARE

                            A:

                            Hi Northgregg, this NGK Iridium IX Spark Plug (TR55IX) - Part No. 7164 pre-gapped at 0.060 inch.

                            Answered on 11/3/2013 by Morgan from AAP
                        • Q:

                          Would these work in my 2000 buick reagal LS?? 3.8 ltr non supercharged..
                          Asked on 5/26/2013 by Justin from St Albans, VT

                          1 answer

                          • CUSTOMER CARE

                            A:

                            This NGK Iridium IX Spark Plug (TR55IX) - Part No. 7164 works fine with your 2000 Buick Regal LS 3.8L. For any further assistance please feel free to call us at: 1-877-238-2623 or visit the nearest Advance Auto Parts store and one of our Parts Pros will gladly assist you with any questions or concerns you may have.

                            Answered on 5/26/2013 by Morgan from AAP
                        • Q:

                          Will these work in a 1997 Ford F15 4.6Liter, I chatted with a representative on here and they said they will, cause they made a recommendation to me that they would. I like the fact that they have lifetime warranty on them.
                          Asked on 4/27/2013 by Brad the man from Fitzgerald,GA

                          1 answer

                          • CUSTOMER CARE

                            A:

                            This NGK Iridium IX Spark Plug (TR55IX) (Part No. 7164) should work fine for your 1997 Ford F15 4.6Liter. For further assistance, please feel free to call us at 1-877-238-2623 or visit your nearest Advance Auto Parts store and one of our representatives would be more than happy to assist you.

                            Answered on 4/27/2013 by Max from AAP
                        • Q:

                          what do they torque at
                          Asked on 3/20/2013 by rich

                          1 answer

                          • CUSTOMER CARE

                            A:

                            For further assistance regarding NGK Iridium IX Spark Plug (TR55IX), Part No. 7164, please provide the year, make, model and engine size of your vehicle. This information would help us to assist you in a better way.
                            For any further assistance please feel free to call us at: 1-877-238-2623 or visit the nearest Advance Auto Parts store and one of our Parts Pros will gladly assist you with any questions or concerns you may have.

                            Answered on 3/20/2013 by Aaron from AAP
                        • Q:

                          i was getting 19 miles per gallon hwy using the standard plugs in my ford f150 with the 4.6 windisor engine. i replaced the standard plugs with the ngk iridium tr55IX plugs to get better gas mileage but i went from 19 mpg to 16 mpg what is wrong
                          Asked on 2/26/2013 by herb back yard mecanic from manning s.c

                          1 answer

                          • CUSTOMER CARE

                            A:

                            Sorry, with reference to your inquiry on the NGK Iridium IX Spark Plug (TR55IX) - part# 7164, without the presence of the vehicle we could neither diagnose the problem nor provide you with a 100% answer. However, I would suggest taking your vehicle to a certified mechanic for a proper diagnosis before buying and having parts installed that may not (solve/be) the problem. For any further assistance, you may also call us at: 1-877-238-2623 or visit the nearest Advance Auto Parts store and one of our Parts Pros will gladly assist you with any questions or concerns you may have.

                            Answered on 2/27/2013 by Vincent from AAP
                        • Q:

                          What is the gap for a 2005 Mazda 6S?
                          Asked on 4/11/2012 by Anonymous

                          1 answer

                          • CUSTOMER CARE

                            A:

                            The owner's manual for your 2005 Mazda 6S specifies the following: I-4 2.3L NGK's ITR6F 13 Gap: (0.049-0.053 in), V-6 3.0L Motorcraft AGSF 22FSCM Gap: (0.051-0.057 in).

                            Answered on 4/13/2012 by Vincent from AAP
                        • Q:

                          what is the gap for 01 gt
                          Asked on 3/22/2012 by Anonymous

                          1 answer

                          • CUSTOMER CARE

                            A:

                            This NGK Iridium IX Spark Plug (Part No. 7164) already comes with pre gapped with 0.060 inch and this part fits your 2001 Ford Mustang GT.

                            Answered on 3/23/2012 by Dennis from AAP
                        • Q:

                          what is the recommended gap for this spark plug for a 1994 ford explorer?
                          Asked on 1/14/2012 by Anonymous

                          1 answer

                          • CUSTOMER CARE

                            A:

                            The recommended gap size for this NGK Iridium IX Spark Plug (Part No. 7164) manufactured by NGK is 0.054 for your 1994 Ford Explorer.

                            Answered on 1/15/2012 by Dennis from AAP
                        Displaying questions 1-10

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