Had lf wheel bearing on nisan ultima replaced two times within a 11/2 time period its bad again. two different shops. whats up?

Possible that one of the u joints in the new drive shaft is bad. If you have a 2 piece shaft then the slip shaft may be dry. Possible transmission mount shifting or bad.

Replacing the LR3/Disco3 rear wheel bearing is not exactly a DYI / Home Repair job. You will need access to a hub puller to remove the axle spindle and a press to push the bearing out of the knuckle (dont forget to remove the giant C-clip / spring that hold the bearing to the knuckle before pressing). You can follow the LR repair manual removing the knuckle. You most likely need to cut the e-brake / drum brake cable plastic cap in the back (most likely fused to the knuckle). Cutting wont hurt the cable and you can reuse it. It will be PITA to reassemble the drum brakes. A good speed shop / machine will be able to replace your bearing within an hr per wheel. Budget 2.5 hrs time per wheel (exclude press time).

What do you mean they are always on

The moment you start your engine any dash
light that stays on tells you that the vehicle has
a failure the need to be diagnosed & repaired

This is not new technology
It has been on all cars since 1983 that's 30 years

You check for codes within a day or two & have the problem resolved within days or a week depending on the issues

You have ABS Braking System issues for a long time,fan &
wiring problems,what gives with that,you don't care about the car

Have a shop resolve all that

Get a different shop to check all of the suspension components - if the struts both snapped, something is going on that's a much bigger concern than the wheel bearings. Look for bent control arms and other suspension components - check clearances and bushings everywhere in the rear, make sure nothing was installed backwards or forgotten. Struts don't just snap, and bearings should definitely not die every couple thousand miles. Also, have a dealer look at it, to make sure that things are installed properly. It won't be cheap there, but they might notice something that other shops routinely miss. I hate suggesting that ANYONE go to a dealership for service, but in this case, they're the most likely to notice something out of spec...

If it was me i would replace the whole thing. You have to ask yourself how long you are going to keep this vehicle. If for a short time, only the bearing. If you will keep it for a longer period of time i would replace the whole thing, while you have it apart.

YEP WHEEL BEARINGS HAS BE PRESSED IN WITH A SHOP PRESS ALSO THE HUB HAS TO BE PRESSED INTO STEERING KNUCKLE.

Usually a roar at speed is a wheel bearing and your hearing the rough roller balls of the bearing making the noise as they rotate while driving. The cost to replace it vaires by the amount of time it takes to remove the old bearing. There is a flat rate but many shops say the flat rate is ______ but that is subject to total job time on a wheel bearing. Usually it costs anywhere from $100- $170 parts and labor.
Bad wheel bearings if they lock up can also many other components if they spin in the housing / bearing race. Do not let it go on for an extended period as it can drastically increase total repair costs.

Thanks for using Fixya.

Kelly

There are, you can go to Parts Source or any larger parts store and you can get different upgrade wheel bearings. The OEM is the best price the dealer can get for parts made, but that does not reflect on your cost for repairs. Good luck and hope this helps. 

There are several reasons why the abs light would come on. Mostly a bad tone ring or sensor within one of the front wheel bearings is bad. To truely know what the actual reason for the light you will need to have a local repair shop or your local auto parts store scan the abs system with a scan tool equipped with abs software. An easy way to rule out a bad wheel bearing , is to raise the front wheels and check for movement in the wheel up and down.