New wheel bearings loosening quickly

[ThreeQuarter]

I have a '94 XLT 4x4 w/ auto hubs, and in the last 1000 miles I have replaced the front wheel bearings & races (& rotors), front axle/spindle bearings, and all related seals. The bearings are thoroughly packed with new Ford grease. I set the bearings using the "preload" procedure described on this board (spin rotor while torquing nut to 35 lb-ft). The key was replaced in the keyway. My auto hubs are working fine. My ball joints are tight.

So why have my bearings loosened twice now in the last 1000 miles? After doing the aforementioned work and the driving around for a week, I went to get an alignment, but they told me my bearings were loose. (?!?) So I re-tightened them this morning, drove 150 miles today for work, and checked them again this evening, and they're just as loose as they were this morning! What gives? (...other than my bearings...)

I've read another thread here posted by someone with a with a similar problem, but nobody seems to have a solid answer. Anybody have a good explanation?

 

[Josh]

Can you rotate the spindle nut with the key in? I wonder if the depth of the keyway is deeper on the new spindles? I would try to turn the nut with the key in just to see whats going on. I switched to manual hubs and the lock nut is torqued to 180 ft lbs and no problems.

 

[ThreeQuarter]

Nope, the keys stop the nuts from turning on both sides. Thanks!

 

[Josh]

Maybe the same procedure, but this time maybe go to the next slot in the nut?? Unless its too tight? That would be my next move. Just be careful not to over tighten them.

 

[RangerX]

What size tires are you running?

 

[ThreeQuarter]

How tight is too tight? I always used the nearest slot for the key, only once (out of four) did that involve backing it off.

Tires: 235/75/15 on stock aluminum rims (see pic in sig)

 

[Tbars4]

...here is a link that might be of interest...
http://www.explorerforum.com/forums/showthread.php?t=199915

 

[kevin25.4]

I had the same problem a couple of years ago . I finally found I didn't press the races in far enough

 

[ThreeQuarter]

tbars4: Thanks for the link. I think everybody in that discussion is referring to manual hubs, and mine are autos--apparently the preload is set differently? And my nut doesn't appear to be backing off, which is what the problem appears to be in that discussion.

Kevin: Races not pressed in far enough? That fits the symptoms. I wonder if the Chinese guy who pressed mine in at the factory went far enough? Should I just keep easing them in every day until they stop, or are you going to tell me I have to take off the rotor, clean out the grease, and do it the right way?

 

[kevin25.4]

I think that will be the only way to get it right. I wouldn’t trust tighten the nut to get it into place.

 

[Explodr94]

I had the same thing happen to me. Went to the alignment shop, they told me that I needed a wheel bearing pack, after I packed the bearings myself. I took the Ex home and jacked it up. The "check" for wheel bearing pack is play in the tire from top to bottom outward. I check my tire and there was play. I took the wheels off and I found that the play was not from the wheel bearings, it was from the hub covers. They have a certain way they go on and then tighten to specs. I reduced the play, but still didn't like it. I ended up getting those round tabs they put on the new Fords to hold the rotor. Then I eliminated the play.

 

[ThreeQuarter]

I don't thinks it's the hubs--I always replace them with the "ears" in the right place. The hub cover seals to the rotor every time.

There is play between the rotor and the steering knuckle, and the bearing nut is loose when I go to adjust it. The problem is definitely in my bearings, just trying to figure out why it's happening.

 

[Tbars4]

...part of setting those bearings is to tap them inward before you tighten them up...the person who did your bearings might of thought the races were fixed with the 1/4" gap in between if he didn't know better...just my thinking, but i'm with kevin25.4...clean them all the way out and start over...

 

[ThreeQuarter]

LOL I am the guy who did my bearings--I guess I missed the tapping part. You mean I should tap the bearings while in place, or the races before installing the bearings, to make sure they're al the way in?

What's this about a "fixed" 1/4" gap? Aren't the races pretty well fixed? I'm confused. I took it for granted that the races were pressed in all the way in my brand new (AutoZone-Chinese) rotors.

Or did I just miss some sarcasm?

 

[Tbars4]

...a little of both...:

...i would try a new set of bearings...install them and check the tightness a couple times real quick...tightening a nut on bearings that might already be damaged could be the reason for your latest results....:scratch:

 

[ThreeQuarter]

Well, I'm taking my chances. After one more adjustment, my LH bearings stopped loosening, and after two more my RH stayed put. I assume this is because my races finally seated. I'm going to at least get what I can out of these bearings (I'm watching them closely) before I give up on them. Thanks for the help!

EVERYONE: Be sure to seat the races in your new rotors!

 

[Tbars4]

......and thanks for the update...i am watching this thread as i hope it too, will help others...

 

[fulfilledstraw]

So how tight can I get these front bearings so that they will stay in? I know the book says 25-35 ft/lbs, and then back off to 25 in/lbs, but my locknut seems to have a little play in that I can twist it ever so slightly with the key in place. Any thoughts?

-Straw

 

[ThreeQuarter]

The locknut should be able turn a little with the key in the slot--that's OK. Play between the locknut & key isn't the concern, it's the play between the bearings & races.

Update on my loosening bearings: Seems I've developed a groan at the front that is not brake-related. Of course my first guess is the bearings...

 

[smtcapecod]

I thought installation of the D44 nut addressed this issue- or is that just for manual hubs?