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Porch Pup
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About mackr1989

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  1. mackr1989

    mack 18 speed problem

    terminology was wrong when they were saying the synchros were bad. the clutches were worn amongst other things. $5200 was the cost of the reman.
  2. mackr1989

    mack 18 speed problem

    the problem was the gears weren’t meshing together when splitting from underdrive to direct and direct to underdrive while in high range..no problem with gears in low range. splitting in high range would put the transmission in neutral and or neutralize then knock into gear. i was told that all of the synchros were worn and thats what was causing the problem. i put a reman in because it wasnt going to cost much more than repairing what i had. now it shifts fine in every position.
  3. mackr1989

    mack 18 speed problem

    no grinding at all. i range shift, move the shifter, then split.
  4. mackr1989

    mack 18 speed problem

    im going to call the company that did the transmission work and relay what you guys are telling me cause i was told much different. if my problem with this transmission was gear splits not meshing together causing neutralization and or rough engagement, what do you think happened to cause this? im now understanding what mach tech is talking about and didn’t at first due to what i was told previously by other people.
  5. mackr1989

    mack 18 speed problem

    in an 18 speed? why do you think i was told that there is 6 and that they were all worn?
  6. mackr1989

    mack 18 speed problem

    so just range as in high and low..not underdrive and direct?
  7. mackr1989

    mack 18 speed problem

    so how many synchros are in this transmission for splitting gears? the only problem ive had is splitting from underdrive to direct and vice versa. never had a problem with high and low range.
  8. mackr1989

    mack 18 speed problem

    well wont a bad synchro cause a a splitting problem? mack didnt come out with an updated synchro design? i was told there were multiple synchros that were worn out. im not disagreeing with what youre telling me. im just repeating what i was told and i dont know much about transmissions from a mechanical standpoint. also, the power divider was accidentally engaged while it was getting worked on. the switch label is worn and illegible and i couldn’t remember if it was supposed to be in the forward or backward position on the dash but did notice that i didnt think it was in the position it was in when i dropped the truck off. i switched the power divider from forward to backward as in “out” and now it shifts just fine. no problems with the transmission and luckily, the power divider still works.
  9. mackr1989

    mack 18 speed problem

    so is the transmission going to stay this way unless it gets pulled apart again? or does it need to be broken in?
  10. mackr1989

    mack 18 speed problem

    turned out that the synchros in the trans were worn out. i was told there was a recall on these and mack updated the synchros with harder metal. i wound up putting a reman in seeing that it wasn’t that much more expensive than rebuilding what i had. i am noticing that it can be difficult sometimes to move the shifter from gear to gear, as in its getting stuck and wont move. ive shifted a lot of different mack trannys and the only other transmission ive used that does this is a six speed low hole..2 stick.
  11. mackr1989

    air pressure drop

    air pressure in 2000 rd dump is always around 95-100 psi average while driving. it will build to 120 but rarely stays around the 120 range. no noticeable air leaks found.
  12. mackr1989

    mack 18 speed problem

    ok so how exactly am i splitting incorrectly. i always kept my foot on the throttle and preselecting to direct for only a split second before releasing throttle, then id let the rpms come down then get right back on the throttle again. total time with this was fast and only took about a second. if this is incorrect, how should splits be done? release throttle entirely, split to direct and engage, then rethrottle?
  13. mackr1989

    mack 18 speed problem

    but as far as repairs and parts?
  14. mackr1989

    mack 18 speed problem

    hmm ok so what do you think is going on?
  15. mackr1989

    mack 18 speed problem

    ive been told to always preselect splits but only just before or after getting on or off of throttle. the only time splits smoothly engage is by preselecting and slowly getting off of the theottle.

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