Front wheel bearing replacement question

So our 2007 with around 134K miles is making a sort of roaring noise from the front end which increases in volume with speed, but doesn't change pitch. Coasting to slow down a little turns off the ICE but doesn't affect the sound any. My son claims that he sometimes hears a sound like metal on a lathe, but the frequency is much too high for my old ears. After driving on the highway, exiting, and immediately checking the wheel temperatures at the center and on the lug nuts they are not found to be hot.

Anyway, seems like it is most likely one or both front wheel bearings, but they are not so bad as to be heating up. The rest of this is all hypothetical, but assuming that is all the problem is...

A set of Timken's would be $220 at RockAuto, and if the mechanic comes in below $600 it would be worth it to me not to have to bust my knuckles. Unfortunately I'm expecting a quote closer to $1000 (for both), and I just can't see that $780 (or more) on labor is a good use for the money. Or maybe it is, depends on how hard it will be to get the bearings out. These are the original bearings, the car has never had any part of the suspension changed. Between my son and I we have a lot of metric wrenches, torque wrenches, and breaker bars. Also impact sockets and wrenches. And a small sledge hammer. What we don't have is any specialized suspension tools. Ideally we would remove the bearing without having to fully remove the knuckle from the car, just remove the brake caliper and wheel speed sensor, and then the bearing.

1. Once the axle nut is removed, is it possible to push the CV axle out of the bearing without unbolting the knuckle? (Mostly to get it out of the way so it isn't damaged in what follows.)

There is a method of removing bearings where a lug nut is removed and a hardened bolt with a nut, washer, and usually some other type of spacer is used to push the bearing away from the knuckle. Sometimes people use 3 bolts, other times they use 1 and move it from position to position.

2. Can one of the studs be removed intact with the bearing in place, or would we have to cut the stud before removing it?

3. Is this method likely to work on this car? (That is, original bearing at this mileage.) The car may have seen some salt for one year in Utah, but the bottom is rust free.

4. If the bearing comes out, is it likely to tear the bearing in half, leaving the outer race in the knuckle?

If the bearing isn't likely to come out that way, we could obtain one of those slide hammer tools which bolt on to the lugs. The force is in the same direction as the preceding method, however this one also pulls on all the suspension components, and might bend something or throw off the alignment, so it is definitely a second choice.

5. Is this any more likely to work than the bolt?

6. If the bolt method left the race in the knuckle, and the CV can be pushed out of the way, is there some adapter which is just slightly smaller than the race which could screw onto the bottom of a slide hammer, so that the slide hammer could pull the race out?

7. Is there any other neat trick for removing the race from the knuckle if all of the above has failed, or is it just time to remove the whole knuckle (and take it to a machine shop, because I have no work bench or vise on which to pound.)

Lastly...

8. Given the age and mileage of the vehicle, would it be wiser just to remove the entire knuckle and take it to a machine shop to have the bearings removed?

9. If we do that, which part of the knuckle attachment system is going to be the hardest to take apart and reassemble, and what special tool would help with that?

I also looked into buying a replacement steering knuckle - to skip the whole "drive the bearing out" ordeal. The OEM part is $312 MSRP, but it can be had for $225.47 at Puente Hills Toyota (maybe less at some other dealer). Dorman makes one too, but theirs is $342 at AutoZone. Too bad it isn't compatible with the Prius C, as those are available for $52 or less at RockAuto.

 

Thanks everybody for the feedback.

It was the driver's side front bearing. But when push came to shove I wimped out and had the mechanic fix it, even though the labor was, as expected, quite expensive.

The rear hubs don't look nearly as complicated. Seems like the whole hub/bearing unit comes off with 4 bolts and is replaced, no messing about with the bearing directly.

 

Our 2007 had new tires put on recently. Since I once had a car with a tire which leaked mostly at highway speeds, and I have to take a long trip soon, today I drove it for an hour on the highway to verify no problems under those conditions. I will check the tire pressures later after they have cooled off and both sides are out of the sun. Now the odd part, every once and a while I walk around the car after a long drive and feel the wheels to see if any are hot. They never are. Except today, a little. The driver's side front wheel was slightly warm - roughly the same as my forehead like right now, just sitting typing this post. That would be about 90F. Definitely a different temperature than the other 3 wheels which all felt slightly cold. Ambient air temp was about 65F during that drive. The car was tracking dead straight, no pull at all, and there were no unusual sounds. The sun was hitting the driver's side (which faced south) during the last half of the drive, but the rear as much as the front.

In short, just a hint of a little bit of friction, somewhere in that one wheel. That is the wheel with the new bearing. Both sides also had new brakes done at that time. I guess for now just keep an eye on it. Even if it is the bearing those tend to take a long time to go out completely.

Edit: mpg does not seem to be affected much if at all. The car was in the "5 minute MPG average display" mode for most of the trip and it was around 50 mpg on average. (Slightly hilly, so of course it goes up and down with the slope.) That is pretty much the same as it has always been before when it had Ecopia EP422s, and the new General Altimax RT45s don't appear to be very much different for mpg. As in, I cannot see a difference yet.