UCABlackChevy

iTrader: (10)

Yesterday, after getting tired of the vibration I was getting at 1/4 throttle or more right before shifting I bought a ES poly mount from Byunspeed.

I took off the tranny crossmember to find that my stock mount had ripped into two seperate pieces (pics below)

I installed the poly mount and started the car...No vibrations at idle at all, No vibrations when I drive like maw maw (like your supposed to). But I still have the vibration at 1/4 or more throttle right before shifting, after it shifts the vibration goes away but if I stay in it, it will start vibrating again as it gets closer to shifting into the next gear.

Does anyone know what might be causing the vibration right before shifting under more than normal throttle?

Oh yeah here are the pics of the factory tranny mount as it came off the car:



Here is a pic of me manually putting it back together:



Here is just another pic for the hell of it:

BlackHawk T/A

iTrader: (3)

My Prothane does the same thing. Vibration, even visibly shaking the steering wheel, a couple hundred RPM before and up to each shift. You need a stock style rubber mount (that isn't torn up) if you want it smooth again, that's all there is to it.

jimmyblue

iTrader: (11)

When your suspension loads up the driveline angle changes.
You can have perfect angle (minimum vibe) at rest, at max
load or some point in the middle but you can't have it good
everywhere. So usually you dial it a couple of degrees negative
so under full torque / load it's zero net angle and min vibe when
the drivetrain is under highest stress.

The tranny mass does a lot to "soak up" the vibration when
it's soft-suspended but the harder the mount the more you put
onto the body via the crossmember. And the body pans make a
nice pair of steel drums.

BlackHawk T/A

iTrader: (3)

I should add that I was talking about part throttle driving and not WOT.

UCABlackChevy

iTrader: (10)

Well, I took it out today and I did a couple of WOT throttle runs and now the part throttle vibration has pretty much gone away except for 3/4 to WOT being the only times I still feel it. Now pretty much any driving I do it feels smooth as butter.

99HUGGRSS

iTrader: (1)

my problem is i have a vibration at 90 MPH and above. would you guys assume i have the same problem. i have all BMR suspension mods. stock mounts,shocks,springs,k-member. i think my angle is set at 0 degrees. or maybe it's the driveshaft??

BlackHawk T/A

iTrader: (3)

Check the suspension forum. Been plenty of threads about that.

99HUGGRSS

iTrader: (1)

ok. thanks.