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  • Treb

    Feb. 16, 2010 7:51 a.m. Treb Reader

    So there'a a road I drive every afternoon, and there's a pattern of skidmarks on that road that is 20+ miles long. And every day, I start to wonder what would make it happen.

    The skidmarks begin on one highway, take the same exit as I do onto another highway.

    The marks are made by one wheel, locking and releasing.

    The marks get closer together on the ramp -- down to a few feet apart -- and are 20-25 feet apart on the highways. At reasonable highway speed, it would be 3 or 4 cycles per second. Each mark is maybe a foot or two long.

    So what would cause one wheel to lock and release at 4 hz for 20+ minutes?

  • John Brown

    Feb. 16, 2010 7:56 a.m. John Brown MegaDork

    Are you sure it is wheel lockup and not a "line erasure"? Sounds like someone removed a dotted line.

    If not it could be a trailer with a bearing locking up.

  • Luke

    Feb. 16, 2010 7:58 a.m. Luke SuperDork

    Extreme axle tramp?

  • DrBoost

    Feb. 16, 2010 7:58 a.m. DrBoost Dork

    Yeah, I think it was a wheel locking up on a trailer.

  • Gearheadotaku

    Feb. 16, 2010 8:26 a.m. Gearheadotaku HalfDork

    Some trucks can lift an axle when not needed. Once in a while they droop down a bounce off the road. If the systems not right, they skip along and leave marks like you describe.

  • Treb

    Feb. 16, 2010 8:41 a.m. Treb Reader

    JB -- it's a tire. It changes lanes on highway #2, and it is consistently in the right-hand side of the lane, or the ramp. And would a bearing locking up be at regular, not speed-related, distances?

    Gearheadotaku -- I like that explanation. Slower speeds mean less energy in the bounce, so closer together on the ramp between the two freeways.

  • mad_machine

    Feb. 16, 2010 8:55 a.m. mad_machine PowerDork

    In have seen some of the "sailors" here with faulty trailer brakes under the boats pull them for MILES until they have a blow out...

  • foxtrapper

    Feb. 16, 2010 9:22 a.m. foxtrapper UltraDork

    I also suspect a trailer. With tramp and a semi-locked wheel. Bouncy bouncy bouncy, chirp-chirp-chirp.

  • iceracer

    Feb. 16, 2010 9:56 a.m. iceracer HalfDork

    Empty trailers often do that. See them all the time.

  • Duke

    Feb. 16, 2010 11:22 a.m. Duke SuperDork

    Especially if it was a 2-axle trailer and only had the issue on one wheel, with the other carrying part of that side's load.

  • Jerry From LA

    Feb. 16, 2010 11:41 a.m. Jerry From LA HalfDork

    Whew. From the thread title, I thought for a second that someone could look at my underpants and see the future.

 

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