Spark Plug Torque and Gap- '94 Suburban

**globalrex** · 11-20-2008, 07:08 PM

Ok i am new to these forums and i did use the search button on this one but couldnt bring anything up...Im not new to working on cars however. I just got a 1994 1500 5.7L suburban 2wd for my job and need to do some work on it. I was wondering if anyone knew of a place to DL the shop manual for free. Also i am going to be changing the plugs on it and was wondering the gap and torque numbers for the plugs!! Thanks in advance!

**vncj96** · 11-21-2008, 05:58 PM

just use your torque wrench and see how much torque it takes to break them loose just dont crank them, use steady and constant pressure,I dont remeber gap but you local parts store dude should know that after all alot of plugs come "pregapped" i always put my plugs in with antiseize compound and go a turn or so past finger tight and have never had problems

**Springthing** · 11-21-2008, 06:00 PM

Found by one of our members. Hope this helps.

**ct9a** · 11-21-2008, 07:38 PM

Originally Posted by vncj96

just use your torque wrench and see how much torque it takes to break them loose

I would be careful doing this with a click type torque wrench as I've been told doing this can throw off the calibration. Dial types should be ok though.

**retired2001** · 11-21-2008, 10:19 PM

Welcome to the site. Have fun!

**IrishBrewer** · 11-24-2008, 09:12 AM

In many instances, the torque to remove a part is much more than the torque that was used in tightening it. Also, you don't know if the person putting it on torqued it to the proper level to begin with. I suppose that if it is an original factory plug, that might not be the case. However, many things get frozen on for one reason or another so it takes a lot more torque to get them freed up. For one thing, the torque required to get them off will be a function of the engine temperature. It is good to have a warm engine but not so hot that you give yourself 3rd degree burns getting to those plugs near the firewall.

When you do replace the plugs, it is a good idea to use anti-seize on the threads to ensure that they aren't frozen on the next time you service them.

I've never used a torque wrench on my plugs, BTW.

One other thing to note on the gap - for my '02 they changed the recommended gap from .060 to .040 so my owner's manual is no longer correct. When I put in new AC Delco plugs all of them had the correct (.040) gap from the factory.

**unplugged** · 11-29-2008, 10:40 PM

I use these two methods:
1. When the plug uses a crush washer, I tighten to seat the plug, then tighten about 1/4 turn to crush the washer.
2. If the plug has a tapered seat I use the specs from the plug mfg. like these from NGK.

**sdavis2702** · 11-30-2008, 02:01 AM

Originally Posted by IrishBrewer

In many instances, the torque to remove a part is much more than the torque that was used in tightening it. Also, you don't know if the person putting it on torqued it to the proper level to begin with. I suppose that if it is an original factory plug, that might not be the case. However, many things get frozen on for one reason or another so it takes a lot more torque to get them freed up. For one thing, the torque required to get them off will be a function of the engine temperature. It is good to have a warm engine but not so hot that you give yourself 3rd degree burns getting to those plugs near the firewall.

When you do replace the plugs, it is a good idea to use anti-seize on the threads to ensure that they aren't frozen on the next time you service them.

I've never used a torque wrench on my plugs, BTW.

One other thing to note on the gap - for my '02 they changed the recommended gap from .060 to .040 so my owner's manual is no longer correct. When I put in new AC Delco plugs all of them had the correct (.040) gap from the factory.

Very good advice