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J2Jake · 12-14-2014, 01:11 PM

Have removed front calipers to replace rotors. Upon checking the pins, the top pins on each side move freely. The bottom however are stiff. They have pink plastic inserts on them. All are greased. What is the proper procedure and grease to service these pins? All four calipers were replaced by servicing/selling dealer after they heated up. Replacing front rotors due to uneven stopping. I did do a search but did not find what I was looking for. Thanks for the reply in advance. Jake

OldToolmaker · 12-14-2014, 02:03 PM

I'm sure you already know this but uneven stopping, I think you mean puling left or right when braking is caused by sticking pistons first, and sticking calipers second. I'm willing to live with a little rattle if my calipers float freely. As for the pistons, you should be able to press them in pretty easily. If one side is harder to push then the other open the bleeder screw. If the piston moves easier, replace the flex line because it's pinched or collapsed inside.

J2Jake · 12-14-2014, 03:16 PM

No problem with pistons, its the pins the caliper floats on that I am inquiring about. Breaking was fine except for the feel of high spots if you will. Jake

OldToolmaker · 12-15-2014, 12:28 PM

Ahhhhh! That thump thump thump feeling in the brake pedal. Happy new rotors! If you don't already, use of a torque wrench when tightening the lug nut helps keep the rotors from warping due to uneven tension.

The last set of tires I had mounted I watched the front tires being torqued to spec. I got distracted waiting for the rears and the tech came up to me and said "you don't have to worry about those coming loose!" I've been doing business with the same tire shop for "awhile" so the tech was told to go and hammer the nuts loose and I torqued them myself.

So are you still worried about your slider pins?

J2Jake · 12-15-2014, 02:41 PM

I spoke with Alliant Coach today, they said the bottom pin does not move as freely as the top. They did give me instrictions on how to clean the pin bore. The bottom pin has 3 plastic sliders built into it. Have to find 3/4 drive torque wrench. Rotor bolts torque to 350 lbs! Ouch, wheel lug nuts to 450. Got some straining to do. Wow.

OldToolmaker · 12-16-2014, 03:09 PM

Quote:

Originally Posted by J2Jake

Rotor bolts torque to 350 lbs! Ouch, wheel lug nuts to 450. Got some straining to do. Wow.

Are those numbers in foot pounds or newton meters? The 5 (front) and 10 (rear) 9/16" studs on my antique Rockwood are only about 160 ft/lb torque.

You'll be happy with a 3/4" drive breaker bar, extensions, socket and torque wrench. They're much easier to use than a 1/2" drive set that turns the wrench and extension into a giant spring.

Bubba1 · 12-16-2014, 06:23 PM

Jake, do know if you have the newer style calipers? There was a recall on our coaches for the calipers around 2005, if I remember right, for dragging/sticking and overheating. I was having continuous problems with the brakes dragging and overheating burning up ABS sensor until I replaced the old style calipers. Now I flush the brake system every two years and haven't had any further problems with the brakes.

Mike H

J2Jake · 12-17-2014, 06:16 AM

Newer calipers, torque spec for hat bolts from truck shop, lug nuts from owners manual.

Bubba1 · 12-17-2014, 05:23 PM

Sounds like you've got it all under control now. Just don't forget to re-check the torque on the rotor hardware after you've driven a couple of hundred miles.

Mike H