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matthearn.com

It burns when I pee. But that's not really your problem, so nevermind.

Friday, December 03, 2004

Repairing my own automobiles is sort of a hobby of mine, precipitated by
  1. the enjoyment of taking things apart, getting my hands dirty, putting everything back together, and discovering with great wonderment that everything works as it should,
  2. the need to demonstrate to myself, my wife, and anybody who happens to walk by that I am a MAN, dammit, and more importantly an ENGINEER, unafraid of anything that technology might throw at me,
  3. the overwhelming desire to not spend $300 on a professional brake job.
Over the past week or so, I'd been noticing a disturbing grinding sound that my truck made when braking, mostly at slow speeds, and getting worse every day. So I stopped by my local Boys of Pep and picked up a set of front brake pads for $36.99, and yesterday afternoon set out to cut my knuckles a little, curse a lot, and bang the hell out of my driveway with a pair of plumber's pliers.

Unfortunately, as much as I love my truck, Ford did not design anything on it with "easy repair by owner" in mind. For example: the oil filter is almost impossible to reach. It's hidden behind a variety of suspension parts near the front left wheelwell, and though you can get a ratchet wrench with a filter-socket to it, you have enough room to turn the wrench approximately 7 degrees, which is barely enough to engage the ratcheting action. So after 3 or 4 minutes of fitting the wrench to the filter, you get to spend the rest of your waking hours toggling the end of the wrench like a lightswitch, like you're throwing a rave under your truck and can't afford a strobe light. Once it's loose enough, you reach up in there and twist it off the rest of the way, usually pouring hot oil into your eyes. The brakes are marginally less eyeball-searing, but much more time-consuming and frustrating.

I started by attempting to jack up the truck, which is when I realized that my regular 2-ton jack doesn't go high enough to get the truck off the ground. I fiddled around for a bit with trying to use thick wooden shims to increase its height, and decided that I feared death a little too much to bother with all that, and got the regular tire-changing jack out of the cab.

After I got the front tires off the ground, I realized I should have loosened the lug nuts on the wheels first, since as soon as I tried to do that, the front wheels started spinning freely. (Yay for rear-wheel drive.) So I jacked the truck back down a bit and started trying to loosen the lugs. Unfortunately, they had been tightened with Jesus Brand Super Godly Impact Wrench Of All Times And Whatnot, so I tried everything short of a blowtorch (which was my last resort) to get the nuts off:

  1. Using my largest ratchet wrench, and banging on it with first a rubber mallet, and then a heavy hammer (which resulted in little more than a bruised finger and a scratched alloy wheel)
  2. Using a smaller ratchet wrench with an extender, which almost stripped the nuts
  3. Looking for the wrench that came with the truck for road-side tire changes, only to discover it's missing, so in the event I have a flat, I better make sure my AAA membership is paid up
  4. Finally putting my large ratchet back on and standing on it while bouncing
At one point I had to rotate the wheel 180 degrees, which of course necessitated jacking everything back up again, turning the wheel, lowering the truck, loosening the nut, and then jacking the truck back up so I could remove the wheel. By this point my frustration was so great that when a nice old lady from the down the street wandered up to ask if I could stop screaming the F-word at the top of my lungs, I replied that it might work better if I just beat her with a jackstand until she was deaf.

Speaking of deaf, remind me to tell you how I didn't get the rotor off later.

Getting the caliper (the part that contains the brake pads. Remember the brake pads? The things I was trying to replace?) off was relatively simple, though the bolts holding it on required some elbow grease in the form of violently beating on the wrench with a hammer and almost breaking my thumb. Once I got the caliper off, I hung it from the frame with a coat hanger (letting it hang by the brake line has the unfortunately result of having the aforementioned brake line, um, break) and set to removing the rotor.

On Sarah's car, a few taps with a mallet loosens the rotor enough that you can just pull it off and inspect/replace it as needed. On my truck, the rotor would not come off even after I sprayed it with WD40 and banged the hell out of it with a heavy hammer for about 10 minutes. After giving up on removing the rotor (it's not strictly necessary to do so to replace the pads, but it makes it a bit easier), I realized that perhaps having my head inside the wheelwell where all this banging was going on was not very bright, because all I could hear was my heartbeat and a high pitched ringing noise for a good 30 minutes.

I pulled the old brake pads out of the caliper and noticed that, indeed, the inside one was worn down to the metal, which was the cause of the horrific noise that's vaguely reminiscent of a dog dragging its ass on a driveway, if that dog was robotic and 37 feet tall, and your driveway was Interstate 81.

The next thing I had to do was compress the pistons; as brake pads wear, the pistons push out more and more so that the pressure needed on the brake pedal to stop the vehicle remains constant, so when you put on fresh (and obviously significantly thicker) brake pads the pistons need to be pushed back into the caliper a bit. The instructions I had from a website said I could, if I was careful, do this with a pair of plumber's pliers. So I got out the old Channellocks and went to work, discovering of course that they weren't large enough.

It was at this point that my frustration came to a rather significant boil. The truck, as it weighs almost 2.5 tons, needs some pretty strong brakes to stop. So the brake pads have something like 12 square inches of surface (compared to something like 7 or 8 for Sarah's 3000 pound Protege) each, and the calipers actually contain TWO pistons. I'm carefully trying to squeeze one of the pistons back into the caliper, at the same time as I'm twisting the whole caliper around so I can actually see what I'm doing, while also repeatedly banging my knuckles on the unremovable brake rotor, and trying not to chip the piston, which is made of some kind of soft composite material.

Good news: the piston finally compressed.

Bad news: the OTHER piston simply pushed out another half inch due to the hydraulic action. Additionally, I chipped the piston a little bit. Also, I pinched the bejeebers out of my finger. Worse yet, the pliers have been thrown through my neighbor's bay window.

At this point I wanted nothing more than a bottle of vodka and a large 8-ball of primo cocaine. However, without a functioning truck, I had no means of acquiring any of Columbia's Finest (even assuming I wasn't joking, which of course I was, since I don't much care for drugs that cause your nasal passages to melt away and your kidneys to bleed), so I either had to fix the truck or wait for Hearnwife to come home and share some of that quality heroin she stores in the hubcaps of her car. (The cops never think to look there. At least until they read my website.)

After squeezing a bit at the other piston (scratching its surface a bit), I finally hit upon a solution: open the brake fluid bleeder valve! Once I do that, it should release the hydraulic pressure that keeps me from pushing the pistons back into place, and then I can put the new pads in, reinstall the caliper, bleed the brakes properly to clear out any air bubbles introduced by the process, and go get a cold one.

Raise your hand if you think it worked out quite that easily. (Put your hand down, dumbass, I can't see you. It was a joke.)

Any attempt I made to try and get the brake fluid to go into a container was fruitless, as it sprayed all over me, my truck, my driveway, and my extremely weak dignity. I was, however, able to squeeze the piston back in enough that it appeared I would be able to put the pads in and fit the whole thing back over the rotor.

WRONG!

The pistons still being at uneven heights, the pads wouldn't fit in exactly right, and they still weren't far enough apart to fit over the rotor. I ended up having to stick various things (ratchets, ratchet bits, my wang, chunks of wood) between them to pry them further apart, and FINALLY managed to squeeze them over the rotor and bolt the caliper back in place. HW came home right about then, and she helped me bleed the brakes, and I went for a test drive: all was well! I am still a MAN, and more importantly, an ENGINEER.

Except, of course, I only did the driver's side front wheel. The other wheel will have to wait until I have more free time and have replenished my supply of Valium.

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