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Posted by: markyb Jun 13 2012, 12:36 PM

I'm getting a bit of vibration and wiggle in the rear of the car at 60-65 MPH, irregardless of the RPM or gear that i'm in, and smoothes out over 65MPH. This would lead me to believe that it's something wrong from the trans shafts outward.

Any suggestions on how to check play on the wheel bearings without a big teardown? Other ideas? Wheels and tires are in good shape and balanced...

Thanks

Posted by: siverson Jun 13 2012, 12:44 PM

I'd try rotating the wheels to double check that that's not the problem. For me, it seems like tire balancing is *always* the problem for these sorts of things.

-Steve

Posted by: Jeffs9146 Jun 13 2012, 12:56 PM

Check your suspension attachment points!

Posted by: 6freak Jun 13 2012, 03:09 PM

wheel and tire balance issues no ?....

Posted by: SirAndy Jun 13 2012, 03:17 PM

QUOTE(Jeffs9146 @ Jun 13 2012, 11:56 AM)

Posted by: vsg914 Jun 13 2012, 03:19 PM

What you describe is classic out of balance tires. How long ago were the wheels balanced? What kind of weights did they use? The clamp on weights won't stay on the Mahles. The glue on weights won't stay on a wheel with dirt, grease, brake dust, and grime on them. Balance jobs sometimes don't last very long. One panic stop and a small flat spot on a tire will throw the balance off.

Posted by: markyb Jun 13 2012, 04:09 PM

I'll try all of the above, stay tuned....

The wheels have tape weights, and balanced about 1000 miles ago. I'm going to try a different tire shop, some of the nearby ones don't impress me at all, and I don't like the way they handle rims around the mounting equipment, tossing them on and off without too much care. While the tires are off I'll do a little snooping around underneath and see if everything feels tight. Hussey said that this car is all original, that might mean there's some things needing attention in the suspension.

Posted by: rhodyguy Jun 14 2012, 08:39 AM

at least you don't have to worry about the employees taking the center caps off with by placing a screwdriver handle against the center of the cap and smacking the the driver with a hammer. after one experience i always do the cap removal myself.

k

Posted by: 6freak Jun 14 2012, 10:10 AM

the colored dots are on new tires for a reason

Posted by: larss Jun 14 2012, 12:49 PM

I had about the same problem with my 914, after trying a ot of wheel balancing I found the problem beeing the surface between the disc and rear hub not being perectely clean. After cleaning the surfaces the vibrations were gone.

Lars S

Posted by: markyb Jun 27 2012, 03:52 AM

After a visit to a more professional shop for tire rebalancing, VOILA! I now have a smooth ride. The tape weights are now on the backside of the rim too for a cleaner look. Now on to other stuff as the ass end on my '75 appears to be sagging a bit. The springs are most likely original so I'll need to measure up bumper height after allowing for a slight difference in the current tire height (185/65-15).

Any suggestions on what brand and where to buy for a set of new rear springs? I looking to maintain a near-stock ride.
The frame and other suspension components are rock solid form what I can gather.

Thanks for all of the ideas, my wallet is much happier that it was something so simple.

Posted by: MikeM Jun 27 2012, 08:22 AM

You are very lucky...mine has the same shimmy and I can't figure it out. Mine shimmies on the hoist so it can't be wheel balance and I've tried everything!!!
Glad yours is fixed!!!
Mike

Posted by: mepstein Jun 27 2012, 08:29 AM

QUOTE(markyb @ Jun 27 2012, 05:52 AM)

Posted by: Dr Evil Jun 27 2012, 11:49 AM

A pic from behind the car may be enlightening. See if your wheels are even and not leaning.

Posted by: markyb Jun 27 2012, 02:26 PM

O yeah, they be leanin' a bit. You can't really see it on the full ass shot, but next to the framing square it shows.

Posted by: Dr Evil Jun 27 2012, 02:37 PM

From more of a distance you can usually see one or both have bad camber. Hard to tell in those pics. Jack up the end of the car and wiggle the wheel from top and bottom looking for play in the arm.

Posted by: 6freak Jun 27 2012, 02:42 PM

QUOTE(MikeM @ Jun 27 2012, 07:22 AM)

Posted by: MikeM Jun 27 2012, 03:09 PM

I mean when the motor is running and the wheels are turning.
I have tried 2 other sets of wheels and tires....same thing.
You were going for a bent rim...right?
Thanks,
Mike

Posted by: vsg914 Jun 27 2012, 04:35 PM

Not an engineer, but I would think anything other than a perfectly balanced wheel would bounce with no load on it. Any slop in the suspension is surely gonna show up.