2004 GMC Sierra Maintenance - MSD Ignition Coil Kit

2004 GMC Sierra Maintenance North Face Graphix Rendering

Are you in the same category as many of us-holding onto your truck and waiting to see what happens with this crazy economy? With truck owners holding onto their pride and joys longer than ever before, we wanted to address this increase in ownership time by providing you a tech section every issue dedicated to monthly maintenance. Maintenance is key to a long term, good-running truck and it may surprise you to find out how many aftermarket companies cater to the maintenance side, in addition to the performance side. We purchased our '04 GMC Sierra dubbed Project Novakane to be a street-driven performance truck and with 144,000 miles and without knowing much about the previous owners' maintenance schedule, we didn't want to drive another mile with old, worn-out parts and fluids.

For the inaugural monthly maintenance story, we focus on today's latest ignition technology from MSD, the always-important proper spark plug choice, and of course, an upgraded oil change thanks to Royal Purple and Fram. One piece of the maintenance puzzle that is often overlooked is the cooling system. Granted, antifreeze technology is better than ever, but like all fluids, it too must be properly maintained. To keep our GMC's 4.8L V-8 running nice and cool, we flushed the system and added Prestone's 50/50 mix of antifreeze and water and then added a bottle of Royal Purple's Purple Ice. This radiator super-coolant additive reduces radiator temperatures, keeps the water pump seals conditioned, and gets the most life out of the coolant.

To do everything we just listed took less than two hours and our Sierra project was running smoother, cooler, and we knew everything was done right, because we did it ourselves. Been putting off working on your truck? Do yourself a favor and spend two hours in the garage. Your truck will thank you and you'll hit that drive to work on Monday morning with peace of mind.

Popping the hood of our '04 GMC Sierra, the 4.8L was obviously given a steam bath by the used car lot we purchased it from in Phoenix. Keep in mind, like a hotel room comforter, just because it looks good from the outside doesn't mean you won't find bad news underneath.
Popping the hood of our '04 GMC Sierra, the 4.8L was obviously given a steam bath by the u
After examining the cracked original plug wires, we contacted MSD for a set of its Gen III LS-engine plug wires, and for a more consistent and stronger spark, we upgraded the factory coil on plugs (COP) coils with MSD's new coil kit. It should be noted that factory coils average $70 each and for nearly the same cost, you can upgrade to MSD performance coils.
After examining the cracked original plug wires, we contacted MSD for a set of its Gen III
Thankfully, the '99 and up engines are a breeze to work on and most things are easily accessible. The old plug wires were simply pulled free from the coils and plugs and discarded.
Thankfully, the '99 and up engines are a breeze to work on and most things are easily acce

After disconnecting the coil wire connectors, we used an 8mm socket and 1/4-inch ratchet to remove the two bolts holding each coil. With the bolts removed, the coils were removed from the valve cover coil bracket.
After disconnecting the coil wire connectors, we used an 8mm socket and 1/4-inch ratchet t
Using a 5/8-inch spark plug socket and 3/8-drive ratchet, each original plug was removed and we were now ready for the new plugs. To get the most out of our 4.8L V-8, we used a set of Autolite XP Iridium spark plugs. These pugs feature a .6mm fine wire design for better ignitability and durability.
Using a 5/8-inch spark plug socket and 3/8-drive ratchet, each original plug was removed a
According to our service manual and engine sticker, the proper plug gap was .035. We used this common ramp tool to set the gap and then easily installed the new Autolite plugs.
According to our service manual and engine sticker, the proper plug gap was .035. We used

As you can see by our sexy hand model, we used the supplied hardware to attach the new MSD coils to the valve cover bracket. The same 8mm socket was used to tighten all of the new bolts.
As you can see by our sexy hand model, we used the supplied hardware to attach the new MSD
A tip we recommend when changing plugs or wires, is to add some dielectric grease to the spark plug boots. This will help keep the plug and wire contacts protected from moisture and corrosion, while also keeping the plug wires from sticking to the plugs.
A tip we recommend when changing plugs or wires, is to add some dielectric grease to the s
After connecting the MSD wires onto the spark plugs, we connected the wires to the MSD coils. A "snap" should be heard or felt when the wire is fully secured onto the plug and coil.
After connecting the MSD wires onto the spark plugs, we connected the wires to the MSD coi