That's what I hadn't considered - I haven't had to do four wheel alignment before. While I imagine it could be done with a similar procedure (measuring rear wear and torque steer besides the front part) it makes a lot more sense to take that to a pro.
Mike
retrogrouch!
in reality, disks offer better cooling, therefore less fade. they also offer more linearity between pedal pressure and braking effectiveness. for a vehicle that potters about town getting groceries, this is not an issue, but for one that gets driven hard, these benefits cease to be so theoretical.
jim beam wrote in news:QLOdna4xzsJi3AbZnZ2dnUVZ snipped-for-privacy@speakeasy.net:
Who, me? Nah...
Absolutely. Which is why *real* performance cars used in *actual* performance applications use them.
True again (you're on a roll here, jim...)
My point exactly. A grocery-getter (which describes 99% of road-going cars) does NOT need rear discs, and in fact is adversely affected by their presence.
"R Flowers" wrote in news:FK6dnVW-malmfwfZnZ2dnUVZ snipped-for-privacy@insightbb.com:
Nor did I, back in the dark days of early 1991...
My famous 1991 Integra famously has those infamous rear discs...
Ever driven un-powered 4-wheel drums? GAWD they were awful. Terrible! Plan your stops in advance, preferably in writing.
And it was akin to a religious conversion: YES LAWD, AH SEE THE LIGHT!!! Discs were a sea-change compared to drums.
Yep. But there is a point of diminishing returns, and rear discs was it. For road-going, legal speed, grocery-getting FWD cars, of course.
Just one question...If disks are so much better, why do the large trucks and tour buses still use drums on all axles? I know there are some exceptions but most use drums. I hadn't really considered this until your above comments...
Dave D
very few of the modern tour buses use drums these days, or at least, not on the front.
the main reason drums are still used on large trucks, especially big rigs, is because of the air brake thing. unlike cars and lighter vehicles, they're "fail safe" which means their "natural" position is full on as opposed to off like a car. strong springs inside the drums press the shoes real hard against the drum, and the air system actuates against the springs to hold the shoes off the drum so the vehicle can roll. if the braking system fails, the brakes come on, and the 30+ ton cargo comes to a halt. hopefully. "fail safe" is much more complicated to implement on disk brakes, but real simple inside a drum. plus imo, a lot of domestic truck manufacturers are not exactly innovative pioneers in the engineering department - the quality of the chrome plating seems to get more attention from what i can see.
I drove a '67 Chevy Biscayne (like a low end Impala) with unpowered 4-wheel drums down a long shallow descent in California when I was a new driver. Within a couple miles I had both feet braced on the brake pedal and was hoping for a place I could coast to a stop. The tranny was a 2-speed "Powerglide" (more glide than power) so low gear was just keeping my speed below 50 mph. I wanted my mommy!
Mike
"Michael Pardee" wrote in news:vaidnXilwfUY5AHZnZ2dnUVZ snipped-for-privacy@sedona.net:
The worst car I ever personally drove was a 1974 Nova with manual drums all around. Now, a '74 Nova is not nearly a '38 Ford when it comes to brakes, but it was still quite a culture shock when you're used to a vacuum- assisted 1975 Japanese disc/drum setup.
So remind me again, how come the Japs got such a foothold over here in the first place?...
Hate to disagree with you but every MCI coach I have driven in the past 10 years, including new ones, all had drums on all axles. I checked with our shop chief and he says it has to do with the larger swept area of the drum/shoe brakes as opposed to the disk/pad brakes. It is true that the disks will not heat up as quickly and are less susceptible to fade and water but the increased stopping power is the reason he gave me.
Actually, there are two systems at work there. The service brakes are activated via an "S" cam and release when the pedal is no longer depressed. You are quite correct, however, that in the event of catastrophic air pressure loss, the failsafe system that you describe will lock up (full on) all the brakes. Rather an unsettling experience I might add.
Dave D
nope. see above.
Plus interstate buses and 18-wheelers are seldom bought on the strength of some advertising campaign (as opposed to passenger vehicles), IMHO anyway.
sure they are! durability, low maintenance costs, that kinda thing. makes the beancounters that buy the fleet truck purchases feel all warm inside.
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