hello, i changed my spark plugs today... and i realized the guy at autozone gave me different spark plugs than i normally use. i usually get the "autolite 45", this time i got "autolite 124". my truck (1977 f250, 300) started up and ran fine after the swap. will this be a problem, or do these different spark plugs interchange?
thanks

 

My 300 had those plugs in them when I first got it so I doubt it will harm anything, I think these are supposed to be used in '73-'74 240 Inline 6's though, same engine except shorter stroke.

 

I thought Autolite was not good for this engine. Search Autolite on this forum and see. I would go Motorcraft plugs.

 

Autolites have always worked good for me, quite a few do prefer motorcraft though.

 

I've never had a problem with autolite plugs in a 300

 

I'm pretty sure autolite is just a different packaged motorcraft or some such thing...

 

I remember we went through this about a year ago on this forum. I just Googled it and found Autolite Plugs, Fram, and Prestone all on the same web site: http://www.autolite.com/home/index.html

 

It's funny cause AUTOLITE used to be a Ford OEM brand of spark plugs.

"Motorcraft Autolites" they were called....

Interesting...

 

i run autolite 46's so they burn a little hotter and burn the oil that gets into the combustion chamber before it reaches and coats the spark plug...needa re-work my engine, me-thinks...

MontanaFord

 

Autolites have never been a problem for me. try em, if they screw up i would go to motorcraft

 

Think the "autolite" brand rights got sold off to Fram's parent company, who also makes filters under the "motorcraft" brand too. Spark plugs and filters are mostly mature technology commodity items, so you'll often get the same item under many different name brands comming off the same assembly line.

As long as it's the correct heat range and the electrode sits in the correct spot in your heads, pretty much any plug will work just fine. In old motors you may need to run different plugs in different cylinders. If you're getting fouling from worn valve seals or rings in a given cylinder [or 2 or 3], bump up to a higher heat range in those cylinders only. If you run "hot" plugs in cylinders burning clean you're just risking pre-ignition.

I've run Bosch platinum plugs for years simply because they don't suffer from electrode wear like regular plugs, so you very rarely need to change them. I have one set in my old Pontiac hot rod with over 100k on them and still work like a champ. The engine has 230K+ miles on it and the valve seals crapped out long ago. Regular plugs would foul out and need cleaning with some regularity. The Bosch's seem to burn off the crud much better and have only gotten pulled once for cleaning, and then they didn't really need it. Yea they cost double a standard plug, but they'll outlast several sets and save you the trouble of changing/ cleaning them.

 

My understanding is that the new Ford vehicles are supplied with a Champion manufacturered Motorcraft filter and all parts supply Motorcraft filters are made by Purolator. So does Allied Signal own one or both of these companies?

Hey, no problem paying extra for good spark plugs. I put platinum Motorcrafts in my F150 I6 last time. Weird thing is the electrode is so skinny.