Need a reply quick, car is on jackstands. Trying to check hub runout in neutral!

Hey guys I'm looking for a quick reply with input or knowledge to something I may be missing .

I have my car up on stands and I'm checking for runout on my front 2 rotors and hubs.

The issue is I took everything off ( caliper, pads) so it's just the rotor bolted to the hub on both sides of the car and the hubs/ axle shafts are very difficult to spin .the point of the test is to see if my wheel bearing Is toast as I've been having lateral wear on my pads.

1) should the hub be spinning on its own or should the hub and shaft be spinning together. I was thinking if its a good quality new hub it should spin freely by itself with no shaft movement. And if its a worn bearing /starting to seize it's giving me this issue where if I turn the hub the whole shaft spins also??


Summary
I understand it is a open differential and only 1 side spins ( whichever I'm rotating) but I don't understand if the hub should spin freely or with the axle shaft also under load. THANK YOU

Hub and axle are 1 when connected so they spin togeather. A bearing failure will show a sloppy wobbly axle and hub.
To check runout, you have to torque down the rotor with a plate. But for the most part should be true.

Ok I torque's down 3 lugs. And I actually managed to " break free " the hub
I put a wrench to the lug and pushed and something gave and rust fell down from the steering knuckle (bearing area) And now it spins better but still with alot of resistance

Its toast. If the car is in neutral it should spin smoothly and with not much force.

Ya I just torque's both sides down to 50ftlbs and neither spin...... like I can't budge it.

So we're saying that's the bearing NOT the transmission differential ?


Because before I torwhed it I could spin it but now torque's to just 50 I can't at all

You're making unnecessary work for yourself.

Here's my bearing when it was really bad.:

https://www.youtube.com/watch?v=-vRR2eMm9zA

The day before this video, I drove from Vancouver to Seattle and back at 120km/h. Didn't notice much other than a little squeaking when turning at low speeds.

Point is, it can get really bad and you can still drive on it. I wouldn't recommend letting it get as bad as this one, but if you can't tell it's bad just by shaking the wheel, it's not bad enough to worry about.

But I can't even spin the thing ? I have lateral wear on 2 sets of pads in 3 months . I changed caliper pads and rotors all brand new leaving the hub and bearing last. There original with 229k km on them. I need to know what's causing the wear so I don't keep wasting money on pads .

Sometimes you can have bad bearings that don't present the same. If they're rusted and not lubed properly they will not show the slop the same. However, if you've been driving it this is unlikely.

Most often the issue causing uneven wear, and/or excessive wear on the pads are the pins not being lubed properly, or the caliper not releasing fully. I've seen both cause horrible wear issues.
Front doesn't have e-brake on Monday so the pins are suspect. In the Rear the parking brake not fully releasing is common. In the end you either clean the pin holes in the caliper and replace the pins lubing then properly, or replace them both for good measure.
Occasionally improperly torqued bearings can cause odd wear on pads, however, a simple push and pull on the top of the wheel will show it and they bearings would be screaming.

Brakes not fully releasing due to pins that are sticky will cause issues with turning wheels, usually not so extensive though

Sent from my Armor_2 using Tapatalk

When i bought new pads rotors and calipers I filled those holes to the brim with silicon grease high temp. I removed them and it was a bit darker in color but still present. I find that once you turn the car on after a brake job and the pins slide a few times. Any grease or pub on the pins get removed by the caliper seals they go into and slide in.

Upon removal today and inspection both the ends where the 8mm Alan sits was covered in Orange grease like new. But the middle and head of the pin was dirty grease / to none at All..

Use brake grease in those pins. It's more resistant to moisture and high temp.

Lateral wear on the pads? Do you mean the leading edge is thicker/thinner than the trailing edge, or the outer edge of the pad is thicker/thinner than the inner?

Either way, I'd think as above that it is the way the caliper is riding on the caliper carrier and pins. I've been finding on mine that the caliper, when brand new pads are loaded, hangs up a little and the inside pad ends up not being pushed in. This is resulting in the inner rotor surface rusting badly and killing the rotors early.

HTH

Cheers,

PH

03tdiwagon said:

Hey guys I'm looking for a quick reply with input or knowledge to something I may be missing .
I have my car up on stands and I'm checking for runout on my front 2 rotors and hubs.
The issue is I took everything off ( caliper, pads)

Click to expand...

but not caliper bracket - could the rotor be touching the bracket? (Wrong size rotor; not fully seated)

03tdiwagon said:

so it's just the rotor bolted to the hub on both sides of the car and the hubs/ axle shafts are very difficult to spin .the point of the test is to see if my wheel bearing Is toast as I've been having lateral wear on my pads.

Click to expand...

not sure what lateral wear means - just wear? Wear on one pad only? Different wear on left vs right side of a pad?

03tdiwagon said:

1) should the hub be spinning on its own or should the hub and shaft be spinning together. I was thinking if its a good quality new hub it should spin freely by itself with no shaft movement. And if its a worn bearing /starting to seize it's giving me this issue where if I turn the hub the whole shaft spins also??

Click to expand...

I doubt your car has freewheeling hubs

03tdiwagon said:

Summary
I understand it is a open differential and only 1 side spins ( whichever I'm rotating) but I don't understand if the hub should spin freely or with the axle shaft also under load. THANK YOU

Click to expand...

the axle stub and hub are connected via a sliding spine (outside teeth on axle engage inside teeth in hub)
In a later post you talk about torqueing. Are you removing/loosening the axle bolt, or just working on the lug bolts (I assume this car has lug bolts, like my 2012 TDI) which screw through the rotor into the hub?

03tdiwagon said:

Because before I torwhed it I could spin it but now torque's to just 50 I can't at all

Click to expand...

i.e. what is the first 'it' you torqued?

Diesl said:

but not caliper bracket - could the rotor be touching the bracket? (Wrong size rotor; not fully seated) not sure what lateral wear means - just wear? Wear on one pad only? Different wear on left vs right side of a pad?
I doubt your car has freewheeling hubs
the axle stub and hub are connected via a sliding spine (outside teeth on axle engage inside teeth in hub)
In a later post you talk about torqueing. Are you removing/loosening the axle bolt, or just working on the lug bolts (I assume this car has lug bolts, like my 2012 TDI) which screw through the rotor into the hub? i.e. what is the first 'it' you torqued?

Click to expand...

these cars the mk4 don't have a caliper bracket in the front, they do just in the rear. The front caliper bolts to the steering knuckle which was 2 threads holes built into the knuckle.

I noticed where the pads sit there is quite a bit of material pickup (fresh metal exposed/ material scraping from pad to steering knuckle)

Have you checked the surfaces were the pads ride? Make sure to clean/wire brush them, lightly dress with a file if needed and lube them. I can't remember if they ride on stainless steel inserts or not. Pads and pins should extend and retract freely. Once assembled retract the caliper with a 6" c-clamp and watch the pads.

How's your brake fluid? Pressure bleed a little into a clear container to check for contamination.

Was the hub cleaned and wire brushed before installing the rotor?

Make sure your final wheel torque is correct on all lug bolts.

Good luck, John

If you use the stock wheel bolts to torque down the rotor WITHOUT a wheel rim they are TOO LONG and protrude out the back of the hub plate and cause interference which stops the hub from rotating! You'd have to use a shorter set of bolts or shim them out with washers or as someone said a plate to account for the thickness of a rim.