I tried to search for this but was unsuccesful. I need to know the screw size for the screws holding the spark plug cover plate. I am pretty sure that they are either 1/4" or M5. I know that someone here must have had to replace theirs as well due to stripped heads.

I called the dealer and they will not tell me what they are and want $6 each for a $0.15 screw and I don't want to use the crappy aluminum torx head screws for the replacement because they will just get stuck again when the motor heats up. Should I go with stainless or zinc plated?

Thanks in advance for your help.

 

take one out, go to home depot and mathc it, haha, best i can tell you. stainless.

 

the problem is i can not get them out, i am going to have to drill the heads off to get the plate off and use pliers to turn the rest of the screy out. i need to have the replacements ready to put the cover back on.

 

Get a set of screw removers for 10 bucks. They work great and you won't risk the drill walking off the screw head and gouging up your plug cover. As for size, yeah just pull one and head to Home Depot. And next time, maybe some anti-seize?

 

they were put in by the dealer when they replaced my timing chain. they must have gone nuts over torquing them.

i have tried the screw extractors and the extractor broke before the screw even budged!

 

I'm on the phone with Partech right now...trying to get you a size...my catalogue doesn't give a size...hopefully GM can give me an answer...just hang tough for a sec...

Bad news...they are telling me it is a GM specific size...won't give me the size...and say you won't be able to procure one locally...sorry...I tried.

Part #12789897 if it helps...and yes...they are expensive for all they are.

 

Thanks for the effort, looks like i am screwed....no pun intended

This must be why GM cant make a pofit. They not only build cars and trucks, but now they design nuts and bolts! What a waste of time!

 

yeah it's like finding the studs and nuts for the downpipe to manifold. They were like 4 dollars a piece or some crap.

 

most likley gonna be an M6x1.25 or M6x1.0

 

They are M6x 1.0 I replaced mine with hex-head 10mm stainless bolts. They look a lot better, and since I change plugs more often since I have stg 2 and nitrous, its a lot easier!

 

Thanks