Is it necessary to repack the wheel bearings when installing new rotors?

 

2 wheel drive?
4 wheel drive?

On 2 WD the a new hub comes with the rotor, no?
I would repack the bearings since it's already apart. No sense in tearing it all apart later to do the bearings.

On 4x4's the rotor comes off seperate, but I'd still do the bearings while it's apart. Doesn't take that long and you'll have piece of mind.

Just be sure to get the bearings tightened properly. Too tight and they'll over heat.

 

On my '97 F150 4X4 I was told by two Ford garages that the front wheel bearings are sealed and do not get serviced. I asked if they'd go 300,000 miles (I already have 197k) and one service guy said no problem. Drive'em till their junk the other said, so that's what I'm thinking of doing.

 

It's a 4x2.

I didn't know the new rotors came with a new hub. I've never changed rotors before.

Is "repacking" just cleaning and regreasing?

 

Clean, examine for wear, repack or re-grease, replace grease seals, and re-install.

 

It's not necessary, but with the one piece rotor and hub assembly for the 4x2 you might as well repack them. When you remove the spindle nut to remove the rotor you'll have to remove the bearing too. They are not sealed like the 4x4's. The bearing slides on the spindle and the rotor/hub slides over the bearing (the race is inside the hub). You can pick up a generic bearing packing assembly for a couple of bucks. After that all you need is a grease gun for zerk fittings ($15) and a tube of bearing grease ($5) and you're in business. It's really easy and doesn't take very long (although it is very messy). It's better than paying a mechanic $70 an hour to do it. I went ahead and spent an extra $50 and bought new bearings and grease seals because I had to get new rotors anyway. My '97 has 115k miles so it was worth it. I got the mid-grade rotor/hubs from NAPA and the races were already pressed into the hub assemblies, which made it easy to do in my driveway.

 

I always understood that you should replace the bearings and races together. The new rotors have the new races pre-installed. It would be a good idea to replace the bearings too. What's another $50.

 

Thanks Brian, really great info. I think I will go ahead and get the components and get to work.

 

don't forget to get "High Temp" grease. Make sure it is made for heavy duty disc brake use.

 

Is there a good synthetic bearing grease available?

 

Are there any tricks to installing new seals?
I was going to use a block of wood and a rubber mallet.