ATD-5401 Spark Plug Insert for 5400 Kit

9:07 am Ford Problems

ATD-5401 Best Price

DennisB © Summary: We sell the ATD5401 at a great price. It’s a replacement spark plug insert that is installed using the ATD-5400 spark plug thread repair kit typically used on Ford 4.6, 5.4 and 6.8 liter engines with 2 valves per cylinder. The ATD5401 replacement spark plug insert is a stainless alloy steel insert that lasts the lifetime of an engine when repairing a spark plug hole from a spark plug blowout. See current pricing on the ATD-5401.

Besides being over-sized, the ATD5401 has a patented lip that helps to repair oblong holes from a failed previous repair when compression loss caused erosion. The outside measurement of this lip is .85″ which is almost 22 millimeters.

The outside measurement of the threaded part is .74″. The larger outside diameter makes this insert usable to repair spark plug holes when smaller parts store kits fail like Helicoil. The ATD-5401 also has the taper seat for the spark plug built-in to the insert. This way there’s no seat preparation tool needed to allow the spark plug to fit and seal properly. Unlike the Dorman spark plug fix, the ATD5401 accepts the original size spark plug which is a taper seat M14x1.25. We currently offer the best pricing on this spark plug insert at the ATD-5401 product listing on our website, You may also order on the phone by calling our toll free number at 800-524-9783.

Brand: ATD, manufactured by Horizon Tools. Call for tier discount pricing for larger quantities.

Outside measurement .74″ on outer part of threads, .85″ on O.D. of lip
Patented lip makes sure there is no loss of compression.
Permanent fix to damaged cylinder threads for spark plugs making the threads 10 times stronger than original.
Replacement insert for the 5400 spark plug thread repair kit.
Replacement spark plug insert for Ford engines 4.6,5.4 & 6.8 Liter 2V’s that have the typical “Blowout” problem.
Used to repair damaged cylinder heads with blown spark plugs without removing the heads.
Sparkplug insert size: M14x1.25 Taper seat insert for the Ford Cylinder Repair Kit (ATD5400). Packaged 1 insert per kit, in poly bag with label. Alloy steel insert.

  • Better than Helicoil.
  • Better than Dorman.
  • Professional, permanent repair.
  • Repair done right over the fender.
  • Oversize repair that fixes previously repaired holes.
  • Won’t back out on next spark plug change.
  • Tough, durable Stainless steel alloy that can withstand the heat and stress of the combustion chamber.
  • Similar properties to aluminum alloy.
  • Your questions answered when you purchase at!
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Please note: Your comment will not be posted until it's approved. We appreciate and read all on topic, relevant comments. Please don't ask for repair manual info like torque specs, wiring diagrams and specific repair procedures. If quick assistance is needed with purchasing a tool or part, please visit our tool website or call to place an order at 800-524-9783. *Note we don't offer repair advice on the phone.