I have a 92 Accord 5 speed with 147k miles on it. It has developed a bad vibration in the front end. It starts around 55mph and get really bad at 65 mph. The engine mounts all appear good, the wheel bearings show no play. All of the various likages/bushings etc are worn (the car has nearly 150k miles) but none show any obvious "wiggle" points. I assume the likely suspects are CV's, carrier bearing and bearings supporting the ends of the axles at the trans. How can I discern which, if any, is the culprit(s)?

All of the CV boots are intact but there is some grease leakage from the passenger side inner boot. Both CV's show a sligh bit of "play" when I grasp the axle and move it.

When I put it on a lift and run it up to 65, the vibration/wobble is readily apparent but I can't determine the source and am aware that at full "droop", all the suspection and axles angles are very different than when sitting on the ground.

Where should I start at the "relace the parts" game?

Have you had the tires checked for a belt separation or a lost balance weight yet? Are the knuckle bearings tight or loose (Does the wheel wobble when shook with it jacked up)?

The tires are in balance. The knuckle bearings are tight (no movement in either 3/9 or 6/12 oclock when the wheel is in the air). This problem didn't appear suddenly but has slowly gotten worse over time. The rate of deterioration has increased recently and it is time to fix.

Axels don't do this, if the joints were failing you would hear them usually in a turn at slow speed... How and when did you verify the tire balance?

Rotate the tires from front to back of the car and see if the problem continues.

Cord separation isn't always visible to the naked eye. I've had this happen a couple times.

Also... if you have a second person to hold the steering wheel tight (you get too much play in the steering lock to do this alone)... grab the wheels at 9 and 3 o'clock and see if you feel slack check both sides... (worn inner tie rod ends or a steering rack that's got worn bushings are a thought that comes to mind as well)

Removed both front tires/wheels. Vibration still there at 55 mph plus. It is reduced (as I would expect with much less rotating mass without the tires/wheels) but it still clearly there.

Also checked the steering as related above. Very good with only the slightest of play at the rack evident. If it were steering component related, would I get the same severe vibration with the wheels in the air? What would cause the "input" to the steering vibration if the wheels weren't on the ground?

Hmm... odd... THe steering stuff would manifast itself mostly while driving I would assume... you might notice it accelerationg but you would notice it braking. Also at certain road conditions like rough roads on turns etc...

Keep I n mind I've always done this sort of testing on the road, and not on a lift. Some conditions can't be replicated.

In a straight line you won't feel much, but on a lift with the wheels in the air... and even with them off and turned you might feel a vibration but it shouldn't be severe. You won't be driving with your wheels turned sharply at 60mph EVER anyway.

Racks are mounted in rubber isolation bushings.. so if its only a tiny amount... I doubt that's it. I was trying to see if the inner tie rod ends were toast... and it appears not.

With the back wheels on the front and the front on the back.. on the road does it change?

If its not tires... then it won't change at all... if it is.. it will change and maybe move to the back.

I assume there was no recent pothole hits that might have damaged a rim.

I actually had several different sets of Bridgestone tires do this in the past...

No change at all with the tires moved front to back.

"Removed both front tires/wheels. Vibration still there at 55 mph plus. It is reduced (as I would expect with much less rotating mass without the tires/wheels) but it still clearly there."
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It can hardly be the tires and wheels if I still have a vibration with them removed.

Tested it again with the tires/wheels off at 60 mph. With no ground friction, only the passenger side is turning and the vibration is still there. You can clearly feel it in the steering wheel/body of the car. The trans/motor is completely vibration free. With only the passenger side turning and the vibration still there, it sort of points to that being the source. i can feel a bit more play in the inner CV on the passenger side than I can on the drivers side. Same CV as the grease leak. i am going to replace the passenger CV as a start.
I feel more "play" at the inner CV on the

If the CV was the culprit you would hear it while turning and driving at low speeds... they can get a little loose without being bad. Basically the diffence between wear and failure. If you ever had one apart you would see the point I was making... when they fail they rarely stay together and litereally come apart ripping the affected boot to shreds in the process of freeing itself.

I'm wondering if you don't have a knuckle bearing on its way out... but you said it was tight with no play on several axis.

Correct all around (including the knuckle bearing) but I am running out of options.

Because of the steeper angle on the right half-axle, its CV joints are prone to failing. I would simply replace that axle ($50).

Your Accord can go well past 300,000 miles. If you plan on keeping it long-term, you are well in the zone for replacing the front wheel bearings, lower ball joints, and outer tie-rod ends. While you have the steering knuckle off, it's best to do all the work at the same time. Since most people hate doing suspension work, the savings are huge for the DIYer that can.

Yep. Went out and bought one, getting ready to break the axle nut loose.

I love doing axle and suspension work on Hondas--wish I had one to do now.

I love doing axle and suspension work on Hondas--wish I had one to do now.

New right side CV installed... no difference at all. Back to pondering the mysteries of rotating assemblies. If it is not the CV/axle and I don't think it is the wheel bearing (seems perfectly tight), that leaves only the bearing supporting the trans end of the axle. Pulling the CV back out Sunday and checking that bearing. After that, it goes to an expert.