97 Lumina front-end vibration

[Bud McGregor]

I have a "well used" 182K 3.1 Lumina sedan with a front end vibration. The vibration stops during acceleration or braking and is speed-affected: it increases frequency as speed increases. I've just replaced rotors and pads because I had a warped rotor and the braking is smooth now though it was quite rough before the repairs. I just noticed the neutral-throttle vibration this morning on my way to work. I will be putting new tires on the front tomorrow but, when I inspected them when I got to work, they did not appear to have any visible vibration-inducing defects such as flat spots, exposed cord, bulges, or splits.
Thanks in advance.

[maxwedge]

This can be tough to isolate, if the tires turn out not to be the issue, I'd be looking at a possible ft axle issue, the inner cv joints in particular can cause this.

[jeffcoslacker]

Yeah, a nuetral load vibration or shake is usually gonna be a an axle joint or a motor/tranny mount, both of which are free to shake when there's no torque being applied...

[richtazz]

my 91 Grand PRix had a vibration like yours and it ended up being a bad outer tie rod. It would start at about 40-45, and progressively get worse. When you let off the gas (or hit the brakes) and got back on it, it would stop vibrating, then start again.