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About mackr1989

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  1. mackr1989

    mack 18 speed makes loud scratching sound

    i do all of those things. i understand how to shift through the gears and the only gear that gives me trouble is usally only eighth while splitting. the other gears only make a real quick scratching type noise in between splits but it doesn’t always happen.
  2. mackr1989

    mack vs pete power

    which will out perform the other, a mack tandem dump with a 400 18 speed..75mph truck or a pete tandem dump with a 500 cummins 6 speed allison that will do the same speed.
  3. i was looking around at available used transmissions online and came across a link for mack transmissions that are supposedly rebuilt by this company? anyone on here ever deal with them? are they trustworthy?
  4. mackr1989


    probably a t2080 with a 300L. we had an 89 rd 690sx dump with that configuration. it topped out at 62 mph. it was geared so ridiculously low that you could start off in 5th gear while loaded. very slow truck with far to much space in high range gears being 5-6-7-8. first gear was useless as it barely got the truck moving. reverse was nice because you never had to feather the clutch. it has a unique shift pattern too. i used to start in 2nd and shift to 4th or 3rd and shift to 5th. the gears are way to close. i hated having the 300L and the mack 8 speed but i think it would be a great plow/sander configuration. i didn’t realize what i was buying.
  5. mackr1989

    18 speed gear split problems

    how much can any one of these scenarios cost to repair? i was expecting far worse cases and these possible issues dont seem to bad.
  6. mack 18 speed in a 2000 rd with a 400 doesnt always fully engage when splitting between underdrive and direct. it will happen wether the transmission is in high or low range. when this occurs, it will seem to just neutralize and grind. what is going on?
  7. mackr1989

    Cracked Frame

    we bought a 2000 rd with 58s last year and the frame had some scale between the rails. i started hitting the frame one day with a sledge to break some of it up and 1 foot hair line cracks started appearing. replaced the rails at donovan in nh for $11k. touch up paint hides a lot when youre selling something...
  8. mackr1989

    pyrometer temp seems high

    if i do have a boost leak, how is the problem fixed and is it expensive?
  9. i need to convert my 12 24.5s to register my truck for 73k in mass. its a 2000 rd688sx randem dump. the tires i have now on the front axle are rated for less than the 18k front axle capacity and i want to convert to aluminum 22.5s with floatation tires. i want pics to see which tire size is both functional and looks best.
  10. 2000 rd's volt meter is pinned all the way to the right as soon as i turn the key to on and while truck is running. any ideas? bad ground? everything electronic works as it should.
  11. the air build up rate in my truck takes a long time to reach 120. is it just time for a new compressor?
  12. mackr1989

    400 to 427

    can i just replace the turbo and notice a difference?
  13. mackr1989

    400 to 427

    can i get the same hp out of my 400 as a 427? of so, how?
  14. my 2000 mack rd with a 400 18 speed has a pyrometer temp that is running between 600-900 degrees while accelerating. i put a thermometer gun to where the sensor is in the pipe and it was reading the same as the gauge in the cab. turbo temp was around 725 at the time that i pulled over to check when the pyrometer was reading around 850. the temperature quickly drops while i start slowing down or run the truck around 1300 rpms. gauge says to not exceed 1100 degrees. is my truck running hot?
  15. mackr1989

    how often to grease

    can anyone tell me how often to grease a 2000 rd688sx ten wheeler dump? 18 front 58 rears. how frequent and where exactly.

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