Possible bad flywheel Help Please!!

[rdlyn13000]

Ok so I picked up this 1995 GMC Sierra Z71 RCSB 305 V8 5 speed 4x4 for an ok deal on craigslist. Well imagine this I got taken for a ride! This was suppose to be a solid truck, I looked over it pretty good and test drove it a couple times with no issues so I bought it. Well it seems the truck desided to fall apart right after I purchased it so ive been working on it more then driving it Anyways here's a list of what I have done to her since I got her and then what my issue is...

New Parts:
Intake Gasket
Harmonic Balancer
Plug/wires/cap/rotor/battery- all AC Delco
Transfer case
Blower motor
blower motor resister
1 ujoint
New pinion seal and changed oil in rear end
coolant flush
oil change

I feel like there's more too but anyways im going to do a fuel filter and rebuild the tbi this weekend also.

Well mt problem is I have this terrible vibration through out the whole truck between 2000-3000 RPMs I thought it was in the drive train but I was sitting in the parking lot and decided to rev it up in nuetral and the vibration was still there. Im kinda leaning towards the flywheel since I think I changed out everything else? What do you all think???

 

[sewlow]

Loose/missing flywheel bolts?

 

[Tempted]

First thing I would do is check for a miss. Flexplates can cause a knocking sound on occasion but they don't even normally cause an intermittent vibration like you are talking about. Start pulling plug wires with the truck running until you find one that doesn't change how the truck is idling. I wouldn't think this is a flywheel issue.

 

[rdlyn13000]

if it is a missfire what else could I do to fix it? I already did the full tune up

 

[Tempted]

Like I said, start pulling plug wires and see if one doesn't change the idle. If it doesn't, check the spark, then fuel, then compression. Tune up doesn't always fix a misfire.

 

[rdlyn13000]

Copy that, I'm doing the fuel filter right now, doesn't look like its ever been done then I'll try that

 

[MattyJ]

why did you change the harmonic balancer?

 

[badazzbulldog]

the truck is a 5 spd correct? so it wouldnt have a flexplate issue

 

[Tempted]

That's why I don't believe it is a flywheel issue. A cracked flexplate isn't unheard of but a fouled flywheel causing his issues are something I haven't run across.

 

[rdlyn13000]

I changed my harmonic balancer because I thought it would help the vibration issue but it didn't.

And yes my truck is a 5 speed, I didn't have a chance to check for a misfire...