MPG up ~17%, rear brakes were dragging

That is good

 

^ There's a link in my signature on this. On a phone, turn it landscape to see signatures.

 

As the recent repair made the MPGs improve, I figure things are probably good now.

 

Should we also check the front brakes?

 

Some people gain mpgs by unplugging & replugging the 12v bat

 

Sure, that should fix the brakes

 

After experiencing the same thing with my caliper slide pins being locked up front and rear I agree. I now dissassemble and lube my sliding pins front and rear every year before winter when i rotate my tires. Excessive of course doing it every year, but it leads to fantastic gas mileage. My peak low was like 40mpg even with all four corners seized up. Now my peak high is typically 55-60mpg. It also makes the brakes last forever too. I really hate sliding pin calipers as they lock up progressively into various positions if you don't keep them lubed up, unlike drums or fixed calipers, but hey thats what we got. Maintenance is really just time as I bet the lube i use is maybe $2 each time.
Also lube up the clips and bend the rear springs out a bit to keep them springy.
I like sil-glyde for the pins and a high temp ceramic grease for the clips.

 

I'm completely in favor of inspecting the brakes at every tire rotation, so typically a couple times a year for me. 'Inspecting' for me is pretty general, I don't go in with plans for any specific parts, slide pins or otherwise, but just to look around and see what, if anything, needs some attention.

In the course of lifting the caliper off the rotor, I naturally get the chance to pull and push on each slide pin, and if they pull and push ok I don't do another thing to 'em. Honestly, in my experience I've found the pins to need about the least attention of anything. They're usually just fine every time I go in. I look closely at the rubber boots for any cracks or damage, and if there's none, a couple pulls and pushes will wake the grease back up and that's that.

What I find most often needing attention are the clips (what Toyota calls the "fitting kit") that support the ears of the pads. Those come from Toyota with a dry, Teflon-like coating so they won't need any grease (which would just collect grit), and when that wears off and then they start rusting, they don't slide well, and I put new ones on.

Other than those clips now and then, most of my inspections complete without doing anything but looking and measuring, and cost $0 except for my time. The benefit of the frequent inspection is if anything is starting to need attention, it's caught right away.

The grease Toyota specifies for the slide pins (and pistons and seals, everywhere there is rubber) is their red "rubber grease", which is a glycol base thickened with lithium soap. They've explicitly said not to use silicone greases there, and I don't know why, but that's what they've said. So I use the red stuff.



No real need to buy a tube of it, 'cause if you ever buy Toyota's caliper rebuild rubber kits, they come with little pouches of the same stuff. I have one rubber kit each on hand for the fronts and rears, in case I ever inspect and find something needed. They're like umbrellas, as long as you have them, nothing turns out to need them.

In this picture, you can see the black arrows and the white ones where different grease types go. The white-arrow grease, used on shims and the like, they call "DISC brake grease" and theirs is gray, and it might be a silicone for all I know. Any shim kit you buy from them comes with a pouch of it.

 

That's very helpful. I guarantee they say not to use sil-glyde because it drys out pretty quick. I'll definitely look into getting that Toyota rubber grease. Ford always spec'd silglyde so I figured that would work for the time being.

 

Sil Glyde’s worked well for me; used on caliper pins of several cars.