Miss fire. I think. Please help

[Moe]

About a week ago my truck started to get a noticeable miss in it. 04 5.3 114,000 all stock original plugs and wires. It seems fine up to about 50 but between 50 and 60 it has a stutter in it. very noticable. I can feel it pretty good. If i just cruise between 50 and 60 and just give it a little gas it does it bad but if i accelerate through these speed to about 65 i don't notice it. It kinda felt like the trans slipping so i dropped it in to 3rd and it done the same thing. I also checked my trans fluid and it seems to be normal. Don't matter the rpm's just the speed. Next day or two i'm gonna change plugs and wires. It couldn't hurt anything. Help me out here. What do you guy's think?

[solidwhite1]

yeah its about time for those, noises with stutter? like clicking or banging?

[GasGuzzler]

Try to duplicate the concern with your left foot BARELY touching the brake enough that the cruise won't set. If it goes away, it's likely you have a converter clutch going south. Kinda need to know what you're driving but some of the utilities (and maybe trucks too?) had a problem of water draining off the cowl and into the trans through the dipstick. The water gets in there just enough to release the bonding of the clutch material on the TCC. The ones I've seen didn't have enough water in the fluid to see on the dipstick but when the pan was removed, they was a layer of milkshake 1/8" deep in the bottom of the pan. Usually the valve body spacer plate will have a rusty look too.

If it's a real misfire, you'll eventually get an SES light. If you can maintain the concern constantly for a mile or so the SES should flash if there is actually a misfire.

[Moe]

No clicking or bangin goin on. It's an 04 gmc sierra 1500 z71 ext. cab. I had a code reader hooked up to it but it didn't read any. I'll try the brake thing when i get out in a little bit. Thanx guy's.

[solidwhite1]

my money is on tha wires

[mnc2fan]

And plugs. Mine did that when I got it. It would stutter like nothing else, almost just short of jumping. Pulled the plugs and there was a 1/8" gap on the plugs..

[Moe]

I hope it's the plugs or wires. Alot cheaper than a trans or rearend. I just don't understand why it does it only around certain speeds. Pay day is thursday so plugs and wires will go in friday.

[GasGuzzler]

You're due for the tune up by miles anyway so it's a good idea to try that. The reason TCC's do this is because it takes a certain amount of load to feel it.