echastain88

I have an 01 z28, cammed, stalled th400 trans that has a pretty good vibration at certain RPM's sometimes its long and drawn out, sometimes its a quick shutter. Usually at 3500-4000 rpms in 3rd (dont know the exact speed, still working on getting the speedo and trans working together.)
Is this a driveshaft out of balance problem?
Any and all help is MUCH appreciated/needed.

1981TA

iTrader: (7)

I'd check the easy stuff first: U-joints, etc. Also, is this a speed-sensitive vibration, or an RPM sensitive vibration (i.e. do you get the same thing revving it up in park?

Z28SteveA4

iTrader: (16)

look to see if you threw the weight on the drive shaft, check u joints, see if there is any play in your pinion and go from there. May sound dumb but its not a vibration from an out of balance tire right??

Blackpanther99

iTrader: (8)

It seems to me like you have a driveshaft problem, do you feel real hard vibrations? As if your car seems like it was wheel hopping? If it is, my truck was also doing the same thing at high MPH between 80-95. I would feel real scary as hell vibrations as if my driveshaft was gonna snap off. Soo I took it to my tuner and he told me my driveshaft was out of balanced. Soo I took it to get balanced about two weeks later and I rev'd it up again that same MPH as last time and there was no vibrations. It could be your U-Joints or a balance problem.

echastain88

Tried revving in park and had no vibrations at any RPM's. So that basically means it has to be something in the driveshaft, correct?

Z28SteveA4

iTrader: (16)

no doesnt exactly mean that but its something in the driveline thats no right

Blackpanther99

iTrader: (8)

Most likely yes.

1981TA

iTrader: (7)

Yup, exactly. I've owned a lot of POS cars, with a lot of vibrations. In order of frequency, most common ailments first: warped rotor/drum, bad u-joints, unbalanced tires/bent wheel, bad axle end bearing, bad pinion bearing, broken/lost drive shaft balance weight.

echastain88

Well then i will start working dow that list and see if i can spot the problem.

Another thing i have noticed, when im cruising along the highway (65-70) if i have my foot on the gas a little, slight acceleration then the vibration is quicker, if i let off the gas and start decellerating then it is a more long and drawn out vibration.

1981TA

iTrader: (7)

Sounds like a tire balance issue. Possibly an alignment problem (you'd see this possibly in unusual/uneven wear on the tires. . If it's brakes, it will be more pronounced hitting your brakes.

echastain88

Ill have a shop look at it monday. On the rims/tires i pulled off when i bought it, there was much more wear on the insides of the tires than the outsides.