Where's the best place to get a deal on all 8 COPs at 1 time. I see the Ebay seller listed in the above sticky issold out.

 

If you want to take a chance on cheap ones:

http://www.araparts.com/

 

Another option. www.rockauto.com

 

Cheapest place is "DON'T" wholesale replace all 8 COPS. They probably don't need replacing, besides all 8 are not going to fail at once anyway. Do everything else first with quality parts, including new COP Boots & springs. Use a brass brush on spring contact on bottom of COPs. Use Motorcraft plugs and do a meticulously clean plug change, using dielectric grease sparingly on the bottom of boots, and COP primary plug.


Then see how it does.

 

I agree with this. Randomly throwing new parts at it, is a ridiculous approach to maintaining a vehicle! If you read through this forum you'll find a LOT of cases of people actually incurring damage while replacing COPs and spark plugs. Also a lot of the 3rd party COPs are bad right out of the box so many people spend a lot of time trouble shooting and eventually end up buying OEM parts. YMMV.

My approach; Wait until it's needed or when it's DUE to be replaced. Buy GOOD quality parts and do the job CAREFULLY so I don't incur other problems and do the job RIGHT. that means clean everything before starting and use all of the right greases, LockTite, anti-seize and put all of the hoses, wiring and connectors back CORRECTLY. Because so many people have problems with them, on something like COPs and plugs, I would do one at a time and test it after each one. That way if one is bad, I know which one it is.

 

However, if you are changing the plugs, I would change the COP boots and springs.

 

Plugs were changed at 100,000 and 2 COPs were also changed. The other 6 COPs are factory original. Truck has 180,000 on it now. I want to change all 8 COPs and all plugs again soon.