Older Corollas have fairly high road noise to begin with. The biggest
noise problem I see with them other than inherent road noise is chopped
rear tires. Some call the wear "cupping", but in a Corolla's case I
would describe it as "diagonal" or "choppy" tread wear. Even if your
rear suspension is aligned perfectly, this can happen to tires when not
rotated frequently (no longer than 7500 miles between rotates IMO).
Add in wheel misalignment and diagonal wear is compounded.

The noise from this uneven tire wear is a low frequency drone that
starts typically around 20 mph. If the tires are really bad you can
hear them under 10 mph. The tread wear can be very slightly uneven and
still cause excess noise at speed.

At 80k miles it isn't very likely that you are experiencing suspension
bushing failure. It is possible that a wheel bearing, esp. rear, is
going bad -- but the fact that the noise doesn't change while turning
would discourage that thought.

Toyota MDT in MO


drnwnr (AT) hotmail (DOT) com wrote:

"Comboverfish" <comboverfish (AT) yahoo (DOT) com> wrote

Bingo!

drnwnr (AT) hotmail (DOT) com writes:

Control arm and sway bar bushings are common culprits. Check
http://www.performancesuspension.com
http://www.suspension.com

"Comboverfish" <comboverfish (AT) yahoo (DOT) com> wrote

Toyota aren't the only vehicles that do this. My sister had a '86 VW Jetta
that did the same thing. If she did not rotate the tires regularly (and she
didn't), the rear tires would develop a weird pattern like you described. It
was like a series of diagonal bands spaced around the tire. The rear tires
would get progressively nosier until it was unbearable - at which point she
would show up at my house to have the tires rotated (for free- the most
important part). When I put the rear tires on the front, the noise would
move to the front. As she drove the car, the front tires would gradually
become quieter but before they actually got back to round, the rear tires
would be roaring again. It was a viscous cycle once she let the rear tires
develop the bad pattern. I assume regular rotation (maybe very 4k miles)
would have avoided the problem, but she never tried that.

Ed

C. E. White wrote:

They certainly aren't. I think diagonal wear has a lot to do with the
light weight rear end, compliant bushings that deflect quite a bit in
turns, and rear independent suspension. Any car with these attribites
will likely wear the tires badly if not rotated.

Alternately, you could have a perfectly normal car, install Goodyear
Invicta GLs on it and experience the same fate regardless of
preventative action. Too bad the Invicta isn't available anymore...

I do an oil change and rotate at 3k on all of our cars. It's on the
plus side of anal, but my tires last >60k and my engines last past the
useful life of the vehicle, all with hard driving.

Toyota MDT in MO

"Comboverfish" <comboverfish (AT) yahoo (DOT) com> wrote


I have my doubts that anal maintenance is cost effective. My sister does
none of those things and she has yet to wear a car out. The Jetta came
close. The transmission failed at 135K miles and I replaced it for her - I
can't see where 3k oil changes would have helped that, or the repeated in
tank fuel pump failures. 2 out of her other 3 cars ended up totaled in a
wreck (after 60k-80k miles). The third, a '73 Pinto, ended up with me and
then a friend's kids. Three of them never wore it out either. It was last
seen heading away with yet another teenager - what a great car (no A/C
though). My Sister's current '97 Honda Civic is well past 100k and is
surviving on 7k oil changes and occasional new tires. As far as I am
concerned it is ripe for dumping. It runs fine, but the paint is dull, the
interior is starting to show its age, and I know who will be stuck with
fixing it if something major breaks (I am thinking clutch).

I am trying hard to break the 3K oil change habit. I honestly believe with
modern cars and modern oils it is a waste of money. I don't consider myself
particularly hard on cars, so I am at least going for the normal service
intervals. My Saturn has an oil change indicator. I have yet to wait long
enough to have it come on. Last time I was over 7000 miles when I finally
gave in to my old oil change habits and changed the oil without waiting for
the light. Out of curiosity, I sent a sample of the oil off for analysis. It
came back as good (the results said I could have gone at least another 3k
miles). So this time I am really really really going to wait for the light.
On my farm, I never change the oil in the farm tractors more often that
specified by the manufacturer. The two largest turbo-diesel tractors call
for 150 hour oil changes. I figure this is equivalent to at least 5000
severe service miles. One of these tractors is 25 years old and has over
6000 hours on the engine. I figure this is equivalent to 210,000 miles of
hard usage. The tractor runs fine, but is definitely showing it age in other
ways (rust, leaking hydraulics, generally out of date design). If there was
any money in farming, it would have been gone 5 years ago. I am sure that
more anal maintenance would not have paid off.

Ed