Every 36,000 miles mate..it is in your manual.Good tip..purchase them from e bay..if you get them from someone who specialises in Renault then they will arrive pre measured so you wont need to use a feeler guage.2 tips on changing the plugs.Firstly...they are deep set so you will need a long reach spanner,8mm if remember correctly.Dont force them too hard as you may snap them..gentle but firm and use a magnetic end to fish them out.A good tip when putting new ones in is use a piece of garden hose to start the screwing in...as its flexible this will prevent crossthreading
no
40,000 km
They come from the factory with platnium plugs. The factory recomends changing every 100,000 miles
No, as long as they were working good before you changed plugs and did not break them while changing the plugs they will work fine.
How many miles should I have before I change my spark plugs
It is 0.9mm
They should not need changing until 90,000 miles.
Spark plugs and wires should be replaced after 60,000 miles depending on the type of driving and the location where you live and drive.
Your Silverado came factory equipped with premium spark plugs designed to be efficent for 80,000 miles. Replace them sooner if you have neglected regular service of engine filters and oil changes, drive in dusty conditions, live in an extreme climate, or do a number of short trips which do not allow the engine to reach operating temperature, or if you have experienced sub-standard quality gasoline. The AC brand plugs you put in will be a Platinum plug, and should give another 80,000 miles service.
one of your wires is most likely loose so check that and if that isn't it make sure your spark plugs are tight
Take the old one out and put a new one in
NGK platinum plugs