new hub/ play in rotor

A couple weekes ago I replaced the front hub on my 91. I kept hearing a clicking noise when turning or braking every once in a while coming from the front left (the side i did the hub on). Yesterday I put the jeep on the lift and found that for some reason there is play between the brake rotor and the wheel studs. If I grab the wheel studs and turn the hub, the studs move in the holes in the rotor and I guess its doing it with my wheel mounted too. The studs are the same diameter as the old ones and Im having a little trouble trying to figure out why this would be happening.

Anyone run into this before? any solutions? Maybe cutting a small sleeve the thickness of the rotor and slipping it over the studs and through the holes in the rotor? Are the studs supposed to have a should on the hub end that the rotor sits on? If so I'll have to put it on the lift again tomorrow and check it out and make sure they do.

Thanks

Did you torque that 36mm axle bolt down to 175ftlbs? Mine would slightly come loose till it forced up against the cotter pin which was enough to get some wobble and rotor noise on turns.

Yes, I did torque it to spec and when I had the wheel off yesterday that nut had not backed off at all. It's almost like the diameter of the studs are too small so the holes in the rotor are not sitting nice and snug on the studs. But the Studs ARE the right size.

anyone else?

Maybe the studs are bottoming out in the lug nuts. I noticed the studs on my replacement hub (Federal Mogul) looked a little different than the OEM, I removed. Noticed the mounting plate for the studs was a little thicker.
The pressure of the rim, against the disc, are really the only thing, holding the disc in place. And it´s not absolutly critical that it be perfectly round, but that it does sit almost perfectly flat.
I measured the studs on my OEM hub, the stud is 1 7/16" long from the mounting plate to the end, the thicker part of the stud (near the bottom, where the disc sits) is 10 MM high and 15MM thick. My measurements are +/-, not exact, but close.
There is a little play between the holes in the disc and the raised stud base. I usually file off the raised outside ridge on the disc, when installing new pads, the raised outer ridge on the disc, sometimes grabs the new pads for awhile, but wears in fast.
Look in the lug nuts and see if there is a build up of junk, rust or corrosion in there.
Check behind the disc and see if there is a buildup on the back of the disc mounting surface, so it doesn´t sit exactly flat. I always grease (copper grease) the flat part of the hub where the studs go through (and the disc sits against), to minimize rust and ease removeal next time.
Might be a dumb question , but after watching my son try to put the disc on, with the front pad in there rear, I got to ask. Are you sure the pads are on right, they are outside and inside pads and not interchangeable.

Thanks 8mud, I didn't even think of the lugnuts bottoming out. I assumed that what was putting on was the same as what I took off. But I should have learned that I shouldn't assume when I first ordered the hub and they sent me one with an ABS sensor, which after going back and forth with the guy, I found that it was foir a completely different car.

As for your not so stupid question (only cause I've seen it done many times), yes, my pads are on correctly. I never took them out of the caliper when I did the hub, but both were put back on right. That thought went through my head, so I did double check that.

We, got a bunch of open ended lugnuts at the shop that have the same thread so I guess I'll throw those on and see what happens.

Did you get the right bearing unit? I don't know whether the 91 has cast or composite rotors, but it makes a critical difference.

As far as i can tell I did get the right one. The numbers on the hub match the number on the box and I had the guy at the parts store look up the number in the book and computer and they all match.

I'm not sure what I have for rotors. How do I tell whether theyre cast or composite and what is the difference between them as to how they sit on the hub or whatever youre refering to?

I'll go into work a little early tomorrow so i can see if the lugnuts are bottoming out and see if I can find anything else.

DDCxj said:

As far as i can tell I did get the right one. The numbers on the hub match the number on the box and I had the guy at the parts store look up the number in the book and computer and they all match.

I'm not sure what I have for rotors. How do I tell whether theyre cast or composite and what is the difference between them as to how they sit on the hub or whatever youre refering to?

I'll go into work a little early tomorrow so i can see if the lugnuts are bottoming out and see if I can find anything else.

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Look at the top of the "hat" on the rotor (the surface the wheel rests on). The edges of a cast rotor are crisp and sharp, those of the composite rounded. The composite rotor has a thinner top. Because of this, the hub itself is a bit longer to compensate. If you replaced only one hub you should be able to measure the two against each other.

My guess is that you got the right one, or the brake would drag on the rotor, but it's worth checking out just in case. Having had time to think about this, I wonder if it's a stud length issue. The studs for the cast rotor are longer than those for the composite, I think, and if you have composite and the correct hub, but they put the wrong studs in, this might do it. If you can, you might try checking the stud length of the new hub against the old.