Another strange vibration

[turbowgn]

Just put in a decent amount of work on my car a few weeks back and now I have a vibration that won't go away. I had Rick (flat4awd) go for a ride and he said he could barely notice it but it bugs the heck out of me! Just asking for your input, any info/advice will help. Taking a road trip to Caribou to see my father at the beginning of August and I don't want to be shaking the whole way. Thanks!

99 Impreza OBS

Sti pink struts with cut springs (will be replacing the springs soon, bought them with cut springs)

04 Wrx wheels (balanced out fine)

03 Wrx 5 speed transmission

r160 from the same 03 Wrx

Running my original obs driveshaft 

New:

Tires

Exedy clutch kit

Lightweight flywheel

Clutch master and slave cylinders

Rear main seal

Resealed the oil/air separator plate

The vibration doesn't start until 45mph and is still there up until 90 ( I wont drive faster than that)

I tried shutting the engine off going down the road, tried rolling in gear with the engine off and clutch in, etc all with no change. tried rotating my tires from front to rear and there's no change. 

Possible causes (I think)

Bad wheel bearing

Warped or bad CV shaft

Need a wrx driveshaft to go with the trans and rear diff

Bad top hat

Cut springs causing vibration

Control arm bushing?

driveshaft center bearing gone bad?

Sway bar links? I don't think this would cause a vibration though. 

 

[Matt]

Did you road force balance the tires and measure the runout or regular balance. It can balance out fine but have a tire with excess runout and vibrate.

 

[SUBARUDE]

Have you had a alignment done?

 

[turbowgn]

Did you road force balance the tires and measure the runout or regular balance. It can balance out fine but have a tire with excess runout and vibrate.

Not sure how to road balance tires, just took them to a shop and had it done. However they didn't shake before I did all this work, and the tires are almost brand new. About 600 miles on them now. I could have just not felt the shake before because I was on softer suspension, when I balanced them at my old job I thought I noticed a hump in the tread but I think I would have noticed a difference rotating them from front to back. 

Have you had a alignment done?

Yeah right after I put my transmission in I had a shop down in CT do an alignment. 

 

[Nigel Prodrive]

does vibration change if you apply the brakes

where do you feel vibration...in steering wheel, in drivetrain, or seat of pants.

your mix of parts between engine and rear diff is a likely culprit. maybe worn driveshaft bearings, or driveshaft reconnected out of balance, or the driveshaft needs to be balnced itself. you can often see lead wights attached to driveshaft to balance it...if you reconnect driveshaft to diff not in same orientation it originally was, this can often lead to weird vibrations that feel like they are coming from rear end, or noises that sound ike they're coming from rear end.

 

[turbowgn]

does vibration change if you apply the brakes

where do you feel vibration...in steering wheel, in drivetrain, or seat of pants.

your mix of parts between engine and rear diff is a likely culprit. maybe worn driveshaft bearings, or driveshaft reconnected out of balance, or the driveshaft needs to be balnced itself. you can often see lead wights attached to driveshaft to balance it...if you reconnect driveshaft to diff not in same orientation it originally was, this can often lead to weird vibrations that feel like they are coming from rear end, or noises that sound ike they're coming from rear end.

I was thinking that was a possibility, on the r160 rear diff yolk there is a white mark which I'm guessing matched up to a certain spot on the Wrx driveshaft. Ill go out and rotate it and see if that helps. Cumberland salvage has an 02 Wrx driveshaft for 100. If it comes down to it, ill go buy it and try it out.

 

[turbowgn]

Well I took the bolts out of the rear of the drive shaft and rotated it 180 degrees and now the vibration doesn't seem to start until about 60. Now it does feel like just tire balance. I'll have to call around and see where there is a tire shop with a road force balancer. 

 

[turbowgn]

Currently getting my tires road forced balanced... lets hope this is it!

 

[turbowgn]

Ok so not to post a million times but the tires did need balancing. They checked them on the road force balancer but determined that they just needed a regular balance. Doing some research online I found a guy with a 97 legacy wagon having the same random vibration and it turns out it was a stuck front brake caliper. I took mine apart and have come to discover that my passenger side brake caliper seems to be sticking which would make sense as to why the vibration comes and goes. Guess I'll be replacing that soon. It must have got rusted up inside when it took me the week to do my transmission swap.