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schwartzy18510

Junior Member
Joined
Feb 22, 2023
Posts
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Location
Sturgis, MI
Ram Year
2008
Engine
5.7L HEMI V8
New owner of a 2008 Dodge Ram 1500 SLT Quad Cab 4x4 w/the 5.7L HEMI. Looking to perform a minor tune-up before doing some towing this summer, but ran into conflicting specs from Dodge when it came to spark plug gap and was hoping someone could shed some light on the situation. I've found OEM sources recommending .040", .043", and .045" and would like to know which is deemed to be correct.

I have attached photos of the various sources I've consulted thus far along with the gap each recommends, and have summarized my findings below:

1) Owner's Manual .043" (PDF page 513)
2) Factory Service Manual.040" (PDF page 845)
3) My Underhood VECI Label — N/A (missing)
4) Random 2006 Ram 1500 VECI Label.045"
5) 2008 Dodge Ram 1500 Rock Auto Catalog.040"/.044"/.045" (with a damning note that OE-recommended gap is .044"!)

As you can see, there appears to be no consensus, even amongst the OEM Dodge documentation. The fact that the listed spark plug type of REC14MCC4 in the Owner's Manual and Factory Service Manual doesn't exist and appears to have been a typo instead of the correct RE14MCC4 number inspires even less confidence.

At this point I'm inclined to simply purchase the OEM Champion 570 (.045") or NGK 5306 (.044") copper plugs and gap them to the minimum spec I've found thus far of .040", but would like input from others on ideal gap, particularly 2006-2008 Ram 1500 HEMI owners who can consult their underhood VECI labels.
 

Attachments

  • Spark Plug Gap — Owner's Manual.PNG
    Spark Plug Gap — Owner's Manual.PNG
    57 KB · Views: 10
  • Spark Plug Gap — FSM.PNG
    Spark Plug Gap — FSM.PNG
    83.9 KB · Views: 9
  • Spark Plug Gap — VECI Label.PNG
    Spark Plug Gap — VECI Label.PNG
    377.3 KB · Views: 11
  • Spark Plug Gap — Rock Auto Catalog II.PNG
    Spark Plug Gap — Rock Auto Catalog II.PNG
    71.4 KB · Views: 11

srv1

Senior Member
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Nov 7, 2019
Posts
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Location
blasdell n.y
Ram Year
2004
Engine
345 c.i. HEMI MAGNUM
I went with what my Haynes repair manual said:Champion RE14MCC4-.045 (It stated the following for other motors:3.7 v6-.042,4.7 v8-.040,5.9 v8-.040 and 8.0 v10-.045) The manual covers 2002-2008.
 

srv1

Senior Member
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Nov 7, 2019
Posts
317
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Location
blasdell n.y
Ram Year
2004
Engine
345 c.i. HEMI MAGNUM
Also fyi,I purchased my plugs about a year ago from rock auto.Best price I could find at the time,$1.28 ea. .
 

427invader

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Dec 21, 2011
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Location
Shippensburg, PA
Ram Year
2004
Engine
Hemi 5.7
I looked up the plugs and gap in my Daimler/Chrysler Corp. 2 book dealership 2004 DR Ram Truck 1500-2500-3500 Service Manual. What I have listed for a 5.7l Hemi is Spark Plugs: Champion - RE14MCC4. Electrode gap is: .045 in. Hope this helps.
 

GTyankee

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Location
El Cajon Calif. 92021
Ram Year
2016
Engine
3.0 ecodiesel
I just refer to the specs posted by RockAuto

They use to indicate which Manufacturer made the OE part
Like in 2008, the OEM Mopar Spark Plug was made by Champion
In 2009, the Mopar OEM Spark Plug was NGK

The NGK Spark Plug Co., Ltd. is a public company established in 1936 and based in Nagoya, Japan. NGK Spark Plug manufactures and sells spark plugs and related products for internal combustion engines, as well as sensors and ceramics for a wide range of applications.
 
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