3.7L Spark Plugs


Greetings everyone,

Finally in the process of changing the spark plugs on my 2006 Sport Liberty with a 3.7L gas engine. The manual says to change them every 30,000 miles but I've waited & now have almost 68,000 miles.

I went to auto parts store & picked the Champion 3344 platinum plugs for it since I could not read the spec on the data label under the hood due to the rubber seal rubbing it away over time.

I removed the most forward plug today to check the condition AND to see what the brand/spec was. Turns out it's a NGK ZFR6F 11G. The electrode protrudes farther out than the Champions that I bought, but the store where I bought the new ones (O'Reilly) gives it as one that will work

Since the Champion seems to be a different heat range than the OE plugs, will they cause any problems if I go ahead & use them?


Almost forgot to mention that the 1st, & only so far, plug I removed was in pretty bad shape. Gap had increased to about 0.070" & the electrode/anode was starting to wear away.
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I would run the correct heat range. I know on hot rods a wrong heat range plug will cause issues.