Driveline vibration.

[MT-2500]

If all else fails make sure the U joints are in time on the 2 piece drivelines.
If not you will get some strange shaking.
Good Luck
Mt

[UncleBob]

have you tried raising the car off the ground and running it up to 60mph and narrowing it down that way?

Don't really suggest this on jack stands. Car lifts are handy for this kinda thing. Thats how we find most of our problems of this nature....assuming its reproducable with no load. Sometimes they aren't

[2.2 Straight six]

Originally Posted by UncleBob

have you tried raising the car off the ground and running it up to 60mph and narrowing it down that way?

Don't really suggest this on jack stands. Car lifts are handy for this kinda thing. Thats how we find most of our problems of this nature....assuming its reproducable with no load. Sometimes they aren't

only other way i can think of reproducing a load is to use either a power or a brake dyno.

[MT-2500]

For the real hard to find viberations the hunter GSP-9700 is one of the best.
It spins them on the car at road speed.
It will almost balance a square wheel.
For the nearest one.
http://www.gsp9700.com/pub/search/FindGSP9700.cfm

[2.2 Straight six]

Originally Posted by MT-2500

For the real hard to find viberations the hunter GSP-9700 is one of the best.
It spins them on the car at road speed.
It will almost balance a square wheel.
For the nearest one.
http://www.gsp9700.com/pub/search/FindGSP9700.cfm

that's only any use if the wheels are off-balance.

[UncleBob]

Originally Posted by 2.2 Straight six

that's only any use if the wheels are off-balance.

no, thats an old school deal. Used to be common to have multiple items in the hub that caused the assembly to be out of balance. IE, the spindle/axle, the drum, and the rim added together.

We have a on-the-wheel balancer from the 70's at work that the owner (old fart) pulls out now and then to get an old car "just right". Never see need for it on modern stuff. And it will only help you if the problem is at the hub assembly. A bad u-joint, drive line, etc, wouldn't do you a bit of good

[MT-2500]

Originally Posted by 2.2 Straight six

that's only any use if the wheels are off-balance.

That is why I posted the link.
Most 50-60 mph vibrations point to wheel balance problems.

quote from the first post on problem.
This car has a driveline vibration noticable in 4th and 5th gear at any speed over 40 mph. it is quite mild except between 50 to 60 mph. At 50-60 it gets worse, (a moderate vibration) and smooths out somewhat over 60, but is still noticable.

It is noticably worse in 5th gear than 4th. It's pretty uniform whether I am on the gas or coasting. Also, it shakes even when I shift to neutral at that speed.