Brake puzzle

Long time, no see, Anthony... How's things going?

First, I'm going to suspect that it is your driving style that has the brakes wearing more evenly. Braking effort is *usually* about a 60/40 split front to back... Under what would be considered "normal" driving style, people use the brake pedal often... Since the front brakes "come on" before the rears, we will experience more front pad wear than you might... You use your brakes only when you have to... and this may have you applying the brake with just enough force to keep the brake wear roughly even front to rear.

Let's spend a minute discussing your rear brakes... In the industry, these are known as a "duo-servo, self energizing drum brake"... The "front" (or primary) brake shoes serve two purposes... First, they do help to slow the car down, but their second purpose is to force the secondary brake shoe in to the drum. We will sometimes see the primarry brake shoe made of a different grade of friction material. The primary brake shoe lining is often a different length than the secondary and can even be a different thickness than the secondary.

One would think that the engineers would have it figured out by now, but the primary shoe always seems to wear much quicker than the secondary.

Where we live and where we drive will have a great influence on brake lining life. In our area, we are entering into the first of our two annual "mud bowls"... Most of our customers spend a good deal of time "off road" (Alberta oil patch, remember?) and it isn't uncommon to do rear brakes several times before these guys are ready for fronts.... Hell, in a rainy year, it isn't uncommon to do rear brakes a couple or four times in a year... Mud can be a techs blessing.

Since you say that your brakes are more than up to the task, I can only suggest that you are looking for a problem where there isn't going to be a problem to be found (flip over enough rocks and you're bound to find a few bugs)...

What ever became of that magazine article you were writing? I was waiting with baited breath to see the final product....

Take care...

Thanks so much for making me feel better and not think that I'm crazy. I have a '96 Explorer with about 128k miles on it. Like you, I'm not an aggressive driver although I won't say that "I am extremely light on the brakes" as you do. I definitely don't use my emergency brake as a substitute for the disk brakes as you do.

My rear pads were replaced at about 90k miles and the front pads are still original. [Even better, I'm still on my first clutch--yes, I'm stick shift, like you, with the V-6 engine.]

I have a cousin who runs a very successful auto repair shop in Chicago who told me this is impossible, but it's true. I do have my brakes serviced (pad thickness check, lube the rails, etc. at the prescribed intervals) and am still on my original factory front pads after almost 13 years.

Based on my history, I'd agree with you and go ahead and get the rear pads replaced now. More than likely, the car will live out its useful life without ever having a front pad replacement.

Craig in Northern AZ

Hey Jim!!!! Great hearing from you. Hope all is well up in the muskeg!!

Incidentally, this year, I did a piece for the Canadian version of April auto issue about whether (and how) Canadians should come down to the states to take advantage of the lower new car prices and the loonies' being on par with the greenback. Very interesting issues, and I can see why Canadian are angry about some manufacturers' non-export policies (though not Ford. Perhaps you have a dealer's perspective?)

As far as the brakes, thanks for the explanation. I'm betting you're right, especially since I use the emergency brake so much, sometimes even when the truck starts to roll. So would you change the rears at this point at a

As far as the story, I am embarrassed to say I don't think they ever used it, and I have no idea why, since the auto editor assigned. But I was a freelancer at the time, and now I'm on staff (though as finance, not an auto writer). So I'm going to push it. I also did a piece about using forums to get computer tech advice, and that ran. So I should be able to update and at least blog the auto one. The more I use forums, Usenet or otherwise, the more convinced I am that it is the BEST way to get help, pretty much no matter what you're into. And when you get experts like you or the Microsoft MVPs, it makes it even better! I will let you know as soon as I can resurrect it!

My 92 still remains near showroom. While I had my tires off, I just Rustoleum-ed the wheels wells and leaf springs, as a do every few years. Looks like a brand new truck under there. I so wish Ford would bring back the manual for the Explorer. Xterra seems like the only choice these days that is close to the Explorer though with a "manny" "Manny!" Hey I just made that up!! :O)

Anyway, thanks again. I'll be in touch!!!!

Anthony Giorgianni For everyone's benefit, please post back to the group

Thanks Craig. Very interesting that you're having the exact same experience. I DID replace the clutch ... but only because the slave cylinder went. So they changed the clutch they were in there anyway. I had the dealer do it, which cost a lot. But I was really impressed with the work. If you don't mind my asking, how much did it cost to replace the rear shoes?

Thanks again for the great feedback.

Oh, here's photos of my 92 back in 04. It still looks just like this!

Thanks Craig. Very interesting that you're having the exact same experience. I DID replace the clutch ... but only because the slave cylinder went. So they changed the clutch they were in there anyway. I had the dealer do it, which cost a lot. But I was really impressed with the work. If you don't mind my asking, how much did it cost to replace the rear shoes?

Thanks again for the great feedback.

Oh, here's photos of my 92 back in 04. It still looks just like this, including the underside!

My rear pads were replaced at a Ford dealer, too. Just remember that these are May 2001 prices!

Labor: $65 (which looks to be 1-hr) Pads: $41.42

I suppose there'd be a small shop charge and tax in addition to the above.

If easily accessible, what was the cost for your clutch replacement?

Craig

Interesting. They want two hours and $189 total. It wonder what a shop manual says.

The clutch and slave cylinder was $1,239 with tax. I checked with other dealers around here - metro New York and Connecticut, and didn't get much better pricewise. I think I might have gotten a lot cheaper at an independent shop. But the last time I replaced a clutch on my old Ford Fairmont, I found lose clips and other indications of a sloppy job, and the clutch lasted only about three years.!!!! That was an independent. This dealer did an excellent job. I can't tell anything was done, other than a change in pedal feel of course. And they even adhesived in the those troublesome tranny plugs that keep falling out on people's manual Explorers (I got the metal plugs, but they were the wrong ones).

I put so little money into this XLT because I baby it and do mostly everything myself that the $1200 wasn't a big issue.

Thanks again for your help.

Anthony Giorgianni For everyone's benefit, please post back to the group

Reading this string, I think Ford dropped the manual transmission in the Explorer because it was just too good a vehicle and they just couldn't get owners to come back! My '97 has almost 250K miles and still runs well, burns no oil, and is a daily driver. I had to have the clutch repaired twice (at

Just this past month I rotated this truck to my son, who is using it to get to work since his SHO was sold, and I picked up a new Mustang GT for my travels. I still have the title for the Explorer and will continue to use it for all the practical stuff needed here on the farm, even after he gets a new car.

=Vic= Bear Gap, PA

Thanks for that Vic. $800. Wow. No dealer I tried anywhere in NY or CT was close to that. I sure do wish they'd bring back the manual! I love driving it. When I drive auto trannys, I feel like I'm in a kiddy car :O)That 240K is amazine.

Wish I would have gotten 160K out of that slave.Mine failed at about 95,000, when the vehicle was about 14 years old.

Anthony Giorgianni For everyone's benefit, please post back to the group

For what it's worth, here is my experience with a somewhat newer, 98 model. A great vehicle with just minor problems in ten years of service. I was never happy with its front brakes, but the pads just refused to wear down, and would go forever. At around 75,000, with 1/4" thickness still left, I finally decided that it was time. Installed Raybestos 'Brute Stop' instead of whatever the original were, and WOW, what a difference -- the thing actually stops when I want it to! Yes, they wear down fast, and even with my light foot don't last more than 30,000-40,000, but they are not that expensive and I can replace them in an hour or so. They also create a lot of dust, which, if you are very concerned about the looks of your ride, you'd need to clean from your beautiful magnesium rims at least once a week. They may even wear the rotors somewhat faster. Yet having to choose between longevity, esthetics and stopping on a dime in an emergency, I know what I'd take. Newer types of friction material, like ceramic may deliver the best of both worlds - no experience with those.

Thanks for that.

I must say that my truck stops pretty well with the factory pads. Though given your wear experience, sit seems to make sense that you're getting a stronger response. I drive in such a way that I avoid hard stops. But then I have to put up with the nuns who give me the finger as they go by because I'm going so slowly :O)

Seriously, I go the speed limit plus five, almost always using cruise control. And I assume that if they can go through the red light or cut or run in front of me, they will. And I leave lots of space between me and the guy ahead, especially if someone gets up close behind me. I figure if I have to use my brakes, I didn't anticipate correctly.If I'm heading around a curve that has a traffic light (as we have on the Saw Mill Parkway in NY), I let cars get ahead of me, and I use their brake lights to let know whether the light ahead is red. Save brakes incredibly. I even stay off the brakes in stop and go traffic!

Anthony Giorgianni For everyone's benefit, please post back to the group

----- Original Message ----- From: "Happy Traveler" Newsgroups: rec.autos.makers.ford.explorer Sent: Wednesday, April 30, 2008 4:44 PM Subject: Re: Brake puzzle

Is that how it works these days. In the old days they used a hold off valve to make sure the rear brakes came on before the fronts because it makes the car more stable to do it that way.

we will experience more front pad wear than you might... You use

Your "hold off" valve was actually called a metering valve. This was required on vehicles with a combination of front disc/rear drum brakes. This was to keep the front brakes from applying before the rears.... This was accompl;ished by "metering" the amount of fluid sent to the front brakes - limiting it, if you will, the movement of the front calipers until the rear drums "caught up". What it never did was to cause the rear brakes to apply "first", rather, it's purpose was to have the brakes apply in unison. Which brings us to the proportioning valve....

The proprotioning valve was there to limit the pressure to the rear brakes. The harder we brake, the more weight is shifted to the front wheels... If we allow the rear brakes to lock up early, the car will swap ends...

Notice we haven't mentioned the residual pressure valve.

Some vehicles used a "combination valve". This was a metering valve plus proportioning valve combined into one unit. But the theory is still the same and it does not involve applying any one axles brakes "first". Something like that is going to be a nightmare from a stability standpoint.

With the advent of 4WABs, all of these functions can be incorporated into the hydraulic control unit.

Misunderstanding both vehicle systems as well as vehicle dynamics can lead to all kinds of problems... Things "these days" work the same as they did "in the old days" as far as dynamics are concerned... Depending on the system, technology may achieve these conditions in a mechanically different way...

That's fascinating, Jim. Thanks for that.

Anthony Giorgianni For everyone's benefit, please post back to the group