Spark Plugs For Older Gmc Truck

[chuckwagon101]

I have an older GMC truck...(1992) and would like to put in a new set of plugs.

 

The old plugs are Autolite platinum and have been in the truck for

6 years. Even though gapped properly, they have never seemed to be the optimum for

my truck. This is especially during idle when it seems to "miss".

 

I used to run the factory plug cr43ts but they would foul and burn lopsided on the electrodes and I would change them yearly. But notwithstanding this bit of inconvenience, the plugs seemed to run more smoothly than the Autolites.

 

I have some time off this week and would like to do the job before I head out on a fairly

long trip to south Texas.

 

Thanks, Chuck

[chuckwagon101]

Ps.....my truck is a fully loaded Sierra 350.

[2004GMC1500CC]

Ps.....my truck is a fully loaded Sierra 350.

Go with the stock AC Delco's.

[GatorFan]

Ps.....my truck is a fully loaded Sierra 350.

Go with the stock AC Delco's.

 

I agree. I think the stock AC Delco plugs would be the right choice for your truck.

[silversport]

check for some kind of platinum plug from AC...one that is made for your truck...you mention the stock plugs run smoother (seemingly) but foul and need to be replaced yearly (remember those days??? )...and the Autolites not running as smooth...look for an improvement on the stock but perhaps an AC plug (or whomever makes it for them...) and perhaps you'll get long plug life AND smoothness...I am using A/C RapidFire Platinum #12s in my 350...perhpas yours will be the same...I sent A/C Delco an email as their site listed the #14 as the correct plug and they agreed with me that it is #12 (I have used them before in GM V8s) but hadn't changed their website last I looked...

Bill