Got vibration problems. Need help please. Video of runs inside.

[wrathchild]

Ok here is the deal. I had a problem with 3rd and 5th gear. When i would leave off the gas and let the motor slow me down i would get a shudder that felt like it was coming from the back of the car. I replaced the ujoints. Still have the shudder problem. There is also a vibration from the top of 3rd gear on up that i can feel in the shifter and throughout the whole car. The trans is also becoming very notchy to shift.

If you listen at the end of my runs on the video in the shutdown you can hear what sounds like a motor winding down, it isnt , its a sound that i think is coming from the back of my car. Any ideas?

Help please

right click

 

[Stang8URMPRT]

It could be an out of balance or slightly twisted driveshaft. Looks like you're runnin' really strong.. What... mid to high 12's at about 110-115? It being at the top of third gear and in 5th could just be because that is when the driveshaft is turning just the right speed to vibrate.

Nick

 

[94TURBO5 O]

Try your universal joints.

 

[Stang8URMPRT]

Try your universal joints.

Read his post... He already changed them.

Nick

 

[wrathchild]

I have an aluminum driveshaft. I'm not sure but, i guess theres a chance that i may have put the driveshaft out of balance by not putting it back the way it was when i changed the ujoints. Even so, if i did , it still doesnt explain why i have the shudder/vibration while off the gas in 3rd and 5th.

On those runs i was only running 12.90's (tranny wont shift and you can tell in the video). I am down 2 mph in the 1/8th. Normally run 87mph and i was running 84.9x mph. I also usually run right around 110 in the 1/4 and i was running 108.

 

[94TURBO5 O]

Read his post... He already changed them.

Nick

My bad read to fast and mis-understood. Thanks.

 

[jpctln]

How do you go about twisting a driveshaft, anyway? I have a slight vibration problem too; in the higher RPM's...probably nothing too far from the ordinary though.

 

[Stang8URMPRT]

Traction+stock steel driveshaft not made for traction=twisty twisty. Seen it many times... Not noticable by the eye, but once put on a driveshaft balancer, it's obvious. They don't twist into knots, but just like having a slightly bent rim and always thinking it's the balance that is out, when all you're feeling is the wheel bouncing or wobbling.

Nick

 

[Stang8URMPRT]

I have an aluminum driveshaft. I'm not sure but, i guess theres a chance that i may have put the driveshaft out of balance by not putting it back the way it was when i changed the ujoints. Even so, if i did , it still doesnt explain why i have the shudder/vibration while off the gas in 3rd and 5th.

My friend recently bent is aluminum driveshaft... They aren't indestructable.

Nick

 

[IndyBlk5.0]

your car sounds sweet man =)

 

[wrathchild]

your car sounds sweet man =)

Thanks

 

[hllon4whls]

For a cheap easy suggestion, try indexing the driveshaft. Turn it in relationship to the rear yoke. A wrench and jackstands is all it will take. Take a pencil or something to mark the original location.

 

[wrathchild]

For a cheap easy suggestion, try indexing the driveshaft. Turn it in relationship to the rear yoke. A wrench and jackstands is all it will take. Take a pencil or something to mark the original location.

Not sure what you mean. I already had the driveshaft off and replaced the ujoints. So if it is out of balance now indexing it wouldnt help any would it?