Front Rotor Size 89 pickup extended cab

Discussion in 'Maintenance/Repair' started by jlvetor123, Jul 5, 2011.

  1. jlvetor123

    jlvetor123 Newbie

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    A few years ago I replaced the front rotors on my Toyota and experienced some scary moments during wet road condition when I got on the brake pedal even a little more then usual and the front brakes would lock up. In over 100K miles I had never had this happen unless I really got on the pedal fast and hard.

    I had them checked out at the local Sears store and was told they were the wrong diameter. Since then I have tried to find out what the correct diameter is for my truck. When I look to buy new ones I see several different sizes which doesn't make since to me unless there is several mm of tollerance. Does anyone know what it should be? My Haynes repair manual doesn't say what it is for the front just the inside diameter of the rear drums which is 254mm to 255mm. Any help would be appreciated.

    Jim
    jlvetor@yahoo.com
     
  2. Litneon

    Litneon Super Moderator Staff Member

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    Well, I don't exactly know the diameter, but as long as the caliper fits over the rotor without rubbing, it's good. And for that matter, if the stock caliper was in the stock location, a larger diameter wouldn't effect the stopping power at all. The only changes could be rotor material or pad material, not to mention that a freshly turned rotor will stop better than a worn one.

    For the diameter to matter, you would also have to move the caliper outward to take advantage of the leverage available, ie. big brakes.
     
  3. TRUCK ACTION

    TRUCK ACTION Grand Toyotaholic

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    88 's are 9.25'':cool:
     
  4. IronNam

    IronNam Grand Toyotaholic

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    also, how are your front tires?
     
  5. kamesama980

    kamesama980 Addict

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    That's my first thought as well.

    Also occurred to me that a bad LSPV could contribute if ALL the braking force is going to the front. Rears don't do a lot alone but working with the front there's a BIG difference.
     
  6. jlvetor123

    jlvetor123 Newbie

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    Rotors

    Thanks for the informaiton. The tires at the time were almost new and I keep the truck lined and balance and rotate the wheels about every 5k. I'm going to replace them again before winter and I'll see how things go this time. I will be replace rear brakes this time also.

    Jim
     
  7. IronNam

    IronNam Grand Toyotaholic

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    I drive with allseasons during winter. (that's just me, though) What tires are you running?

    I say you should pick up an extra set of wheels and tires for summer. all seasons on those.
    for winter, even the stock steelies paired up with snow tires would be great.

    Braking and locking up can always be a bunch of different factors on many angles and road surfaces. if it's slick out, i'll keep it slow and brake early. Bunch of factors. Let us know Jim!
     
  8. TRUCK ACTION

    TRUCK ACTION Grand Toyotaholic

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    There a lot of veritables that could cause this:
    Air in the system,causing uneven braking @ one or more wheels
    Lose mounting bolts @ the calipers
    Sticking caliper
    Uneven wear @ the pads
    Damaged rotors
    Rotors were not seated in ( there is a specific way you wear in new rotors)!
    Any of these would cause what you are saying!!:cool:
     

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