Hub temp after disc swap

[oldiron]

Just finished the disc swap using Chevy calipers. All new everything. My hubs seem warmer than I remember them being on other swaps. Bearings are all set to factory spec, 50lbs then back 1/4 turn. My ir thermometer says 120°. That was after about 20 minutes driving and some heavy braking. Is 120ish normal?
Greg

 

[SteveL]

Are the pads dragging after braking?

 

[DirtDonk]

How much braking was involved in that 20 minute drive?
Did you brake a fair amount just before stopping and checking?
Probably a little higher than normal, but not unheard of.
At 120 you can still keep your hand on it?

How much torque did you apply to the bearing outer lock nut after the quarter turn?
When you look over the top of the tire and down at the caliper, how much daylight can you see between the caliper and knuckle?

I’ve noticed a tendency for the hubs to be hotter with disc brakes, but never measured the temps!
Mine run a bit warmer, but still easy to keep a hand on.

 

[oldiron]

Hey Paul,
Quite a bit of braking, some of that being "spirited" to seat the new pads. Torqued the outer nut to around 90 ft lbs. I can hold my hand on it comfortably. I just don't remember them getting this warm. Plenty of room between the caliper and knuckle. I feel like I'm ok with this but wanted to check with the group for confirmation. Btw residual valve was removed, no drag that I notice.
Greg

 

[DirtDonk]

Sounds good then. You’ll find that after the braking, it actually takes quite awhile for the hub to cool down.
The brake rotor does impart a lot of that heat to the hub, but I don’t know if there’s ever been a study that states whether a drum or a disc transfers more, less, or the same amount of heat.

 

[ntsqd]

120° isn't going to bother any quality grease. I use Redline CV2 and it's temperature service range is -100° to 500°A quick look at a grease mfg's page showed that the lowest temp rated grease was still over 400°

Did you lubricate the calipers on the pins with some silicone grease? Sometimes a sliding caliper like those won't easily slide, and that drags the pad (inner, usually) and puts a lot of heat into all of the surrounding parts.

 

[Broncobowsher]

I don't see an issue. It's 'I can't touch it' hot that I find a problem. Brakes generate heat. That cast iron conducts heat. I have known of some vehicles getting aluminum wheels to help cool the brakes as there was too much heat and steel wheels didn't conduct enough heat away fast enough,