The Caddy has 78Kmiles and was taken care of by a dealer until about a year and a half ago. When do you change the plugs on one of these? It runs great. The idle seems a little rough for an 8 but nothing to worry about. I thought plugs might help since I am sure they have never been changed. (the mother-in-law owned if for 10 years and did whatever the dealer told her it needed and put 37Kmiles on it). Do I need to worry about getting the plugs out of the aluminum heads?

 

they say the platinum plugs are good for 100k, oh yes and they said dex-cool is also.... yea right. if i were you, i'd change them. i changed mine, on a 99 sts at 50 k mi, and by the way, i'll change coolant every 2 years in the N*..... for sure!
rickyd

 

Ya GM says alot of things and thats how they make most of their money. They like to also say the northstar engine can run with out oil! I havent tried it yet and dont plan to either.

Anyways yes the platinum plugs are able to last longer than the older plugs. They also do cost a lil more money so if your on a tight budget and want a good quality platinum plug for a good price id go with NGK platinum. IMO they are just as good as the OEM plugs and are alot cheaper too. NGK only makes Platinum and Irridium plugs i believe and thats what i use in every car i own and have never been unsatified with the performance. NGK's are around $2-$3 a piece next to the BOSCH Platinums which i had used in the past and was ok with until a friend told me about NGK.

 

Engine should be cold when changing plugs and install a dab of anti-seize on threads before installing. You might want to check coil towers for corrosion and a dab of dielectric grease to coil and spark plug where plug wire attaches, while you are changing plugs.

 

When it comes to "Platinum" plugs there are several types.
GM Delco uses DUAL electrodes, some others use a single electrode.
huge difference in longevity and performance.

Dual electrodes have a long long life.

I used to change plugs at 15,000 miles, old school.

with the modern Delco dual platinums, my philosophy is "if it aint broken, dont fix it" ...

What slowroll said on di-electric, IMO, a must.


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