What Spark Plugs to use in a '03 Z71w/5.3L

[rgdepew]

I replaced the spark plugs in my '03 ECSB Z71 W/5.3L v-8 due to another problem. When I replaced the plugs, I installed Bosch Platinum 2's. When my mechanic found this out he suggested that I go get some AC Delco plugs and put them in.

 

Has anyone used these Bosch Platinum 2's? If so, do these plugs tend to work well with our GM trucks? I have heard that these plugs work well with some vehicles and not others and I was wondering if anyone has used these plugs in GM trucks and if they work well.

[Norseman]

NGK TR55 GP !!! They cost less than the A/C and my 5.3l runs better with'em.

 

O'ya Bosch Plats are complete cr@p, total waste of money, and dont work well in these trucks!

[C & A s Dad]

I have had no persoanl experience with Bosch but have ready many posts that agreed with Norseman. I am not 100% sure about your '03 but my '02 came from the factory with NGKs. They are hard to beat and you will not find any negative comments on this forum about them.

 

BTW If you did not replace the wires when you changed the plugs, you may want to consider it this time around. Internal damage can and likely wil occur when you are removing the OE wires. You will not see this damage but it will affect your performance.

[MrLM7]

Try Autolites.

[az'03Silverado]

Did the Bosch plugs give you any problems? If not, there's no issue. They're not junk. They put them in BMW's, VW's, Mercedes. I've put the +2's and +4's in my cars with ZERO problems. No loss in MPG and no performance issues. JUST DON'T TRY TO GAP THEM!