i was just wondering when should one replace the coils? i have 90,000 miles on my '99 5.3. also how long should i go on my spark plugs? i have already changed them out probably 2-3 years ago with the NGK but i heard they burn out faster than stock. i have gone well over 30,000 miles on the current plugs should i replace them? i have also switched out the wires probably the same time i did the spark plugs.

if i do need to replace the coils shoud i just go stock or aftermarket? what company and how much? thanks for the help....

Randy

 

I Have Seen Truck Come In The Shop With 320k And They Have Not Change Theirs Unless They Broke

 

The coils should be fine. If you replaced the factory plugs with copper NGK's (TR55's or TR6's) 30k ago, I'd replace them (NGK TR55's are pretty cheap...less than $2 a plug). Wires should be fine too if they're quality wires and not cheap aftermarket wires.