Terrible front wobble. Bearing/ spindle spacer question. Options

[roundtwo]

Front bearing / spacer help - so close to on the road

914 six almost ready to go after getting it tuned on a dyno today. More about that later.
- trying to chase down the source of the shaking front end.
- Vetted out wheels, tires, tie rods, shocks, bushings, rotor warpage, etc…. All good
-Please see pics.

It seems as if there’s a mismatch between the inner bearing and the spacer. Somethings not right but I don’t know what it is.

The last true leftover problem from the previous owner.

24 mm carrera rotors, Porsche Brenbo brakes, 911 hubs,
new bearings and seals.

Any clue at to what’s wrong?

[roundtwo]

[mepstein]

The hub and bearings either fit on the strut or they don’t. If they fit and spin smoothly, they aren’t going to wobble.

I would try a different set of wheels and tires on the car. It’s usually the tires that are the problem.

[mate914]

Tires can do what you are feeling. I once changed out a whole steering rack 0n a 914 with a bad vibration. The tires I had looked ok but were the problem. Try moving tires around on the car and see if any thing changes.

Matt

[mb911]

I believe Todd replaced tires already. I have had issues with spindles and bearings in the past but usually it’s the bearing and the race. What can happen is the race migrates into the hub and not allow the hub to be snugged effectively and cause some wobble

[rfinegan]

What wheels? Hub verse lug centrical wheels gives hi speed shake when the wheels are not mounted /torqued correctly

[Superhawk996]

Everything you measured has nothing to do with the surface the bearings ride on. What you are measuring is where the hub seal rides.

You may want to measure the spindle OD vs the bearing race ID.

You don’t detail how you ruled out tires and wheel imbalance. That is the far more likely source as others have pointed out.

[mepstein]

We had a customer with a similar issue. He swore it couldn’t be the tires because they were new, balanced, ect. Paid a shop big money to do it.
I threw on my wheels ( cookie cutters- plain Jane tires) from my 914 and the car drove smoothly at all speeds including 95+. He had some words with the other shop.

[technicalninja]

My first Z pulled violently to the left.
Had a bent strut and some other things I fixed. Full on alignment by a wizard...
Still pulled left HARD, Dangerous!

Corky Bell, who I worked for at the time, said put his car up in the air, steal his wheels and tires and try them on my car.

Fixed it right up!

Could not see anything wrong with my tires!

I second Superhawk's suggestion.

You're measuring the wrong spots...

[ChrisFoley]

With the car up in the air, grab a wheel at top and bottom and try to rock it up and down.
Anything wrong with the wheel bearing fitment will show up right away. The wheel should move only a small amount when the bearing preload is correct.

[Superhawk996]

With the car up in the air, grab a wheel at top and bottom and try to rock it up and down.
Anything wrong with the wheel bearing fitment will show up right away. The wheel should move only a small amount when the bearing preload is correct.

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[technicalninja]

Right after you do what Chris suggests spin the wheel and align the tire tread surface with a straight edge you place on the floor.

The human eye can see .001" of run out.

If you have a bulge, internal tire issue, you can often see it this way.

Has to pass Chris Foley's test FIRST!

I set my adjustable wheel bearing clearance so there is almost no play at all.

If you're using new bearings and races recheck this clearance after the first 100 miles.

Most need a tiny bit of "tighten" at this point.

[Superhawk996]

Right after you do what Chris suggests spin the wheel and align the tire tread surface with a straight edge you place on the floor.

The human eye can see .001" of run out.

If you have a bulge, internal tire issue, you can often see it this way.

Has to pass Chris Foley's test FIRST!

I set my adjustable wheel bearing clearance so there is almost no play at all.

If you're using new bearings and races recheck this clearance after the first 100 miles.

Most need a tiny bit of "tighten" at this point.

Though I agree with all above, it should be noted that you can’t see imbalance and you can’t see radial 1st harmonic tire (R1H) effects but they surely can be felt on the road as the symptoms you describe.

At this point, it no longer surprises me when tire shops screw up simple balance.

Finding tire shops with road force machines with technicians that actually know how to use them properly to counter act a tire with a high R1H problem is a task unto itself and you will pay “extra” for road force balancing.

[technicalninja]

(IMG:style_emoticons/default/agree.gif) (IMG:style_emoticons/default/agree.gif) (IMG:style_emoticons/default/agree.gif)

However, if you can see runout/big bulge the additional issues mentioned don't mean anything.

I agree, check wheel bearing play, check tire run-out visually and if you don't hit an issue look to balancing/weird tire problem.

If I cleared the first two steps, I'd either move wheels front to back OR if I had another set available I'd swap wheels.

My step was a "next one" that can be accomplished during the wheel bearing play inspection.

I got a new set of wheels/tires for my Veloster yesterday. Weight marks NOT where they were supposed to be.
The Veloster is a first for me!
I've changed tire/wheel sizes for the second time. 18 to 17 and now 17-16
I went -2!

It takes the same sized tire that I put on the upgrade Fuchs for the 914!

So, an econobox got degraded to the same size the 914 got upgraded to.

There's progress for you!

[infraredcalvin]

Agree on tires, i put Toyo r888rs on both my cars, if they sit for more than a week they get a flat spot, once the tire warms up a bit it goes away…

[Krieger]

Did you check to see if the steering rack is tight? Also, some spindles are very worn. You can tell when you go to adjust the wheel bearings. There is too much play no matter how much you tighten the outer nut. The bottom of the outside end of the spindle where the bearing rides can wear. It has a step that you can feel with your fingernail.

[roundtwo]

@chrisfoley
@rfinegan
@mb911
@mate914
@mepstein
@technicalninja
@superhawk
@infaredcalvin
@rfinegan


Thanks everybody for all the responses.
Do my best to cover the topics
1. New Pirelli CN thirty36s Road force balance by Harvey W after the wheels were dialed guaged spun then refinished.
2. Harvey and a wheel specialist in the Bay Area both checked the wheels for trueness, etc.. both said good
3. Previous tires on the wheels had the same symptoms. Toyo r888 that probably sat for a bunch of time before I purchased the car. We’re nearly unwarn.
4. Chris foley shake test. No slop. Steering rack no slop side to side. New, Turbo tie rods. New inner and outer bearings with races. New spindle spacer. New bushings. Everything checked by me and also an alignment specialist at Sonoma Raceway corner, balance, the car and adjust to the right height, did the alignment. Race is fully seated. Spindle space are fully seated. I don’t see any bend in the spindles. All with 500ish miles before the wheels were restored, and new tires mounted.

5. Nick’s plan to try Chris at the red barns front wheels on my car to see how it drives. Hope to put my wheels on his car to see if he has any new imbalance on his front end.
6. Bearings adjustment quadruple checked leaving them slightly tight vs looser side.

Will post a couple pics with a couple questions
On

my best guess is the wheels are out of balance

[roundtwo]

[roundtwo]

See previous pic

1. When I slide on the rotor hub assembly surface B on the spindle comes in contact with surface “B” on the inner bearing in the rotor.
2. Is it correct that when rotor is fully installed the rotor pushes on to the spindle spacer to the point that leaves a gap labeled “A” ? With the rotor fully on, I can see that yellow highlighted zone about three or 4 mm that has nothing in contact with it.

3 . Is the spindle supposed to come in contact with the inside of the bearing in the rotor?
Or is it designed that the spindle spacer outward edge contacts the back of the bearing?

4. Is the bearing supposed to come in contact with the base of the spindle spacer where the flange begins ?

Thanks for all the help

[ChrisFoley]

The inner bearing inner race is supposed to contact at B to B. There should be a little space at A. The grease seal rides on the smooth flat cylindrical surface nearby. Nothing should contact the flange surface at A.