New to the 9 Speed...downshifting killing me

Discussion in 'Questions From New Drivers' started by D3m3nt3d, Jan 14, 2009.

  1. D3m3nt3d

    D3m3nt3d Bobtail Member

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    Oct 18, 2008
    Eastern NC
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    This is great advice, funny thing is I was doing just this today - altho I didnt write it down, I stored it into my memory bank.

    I did alot better today with my downshifting, though I did grind a few times - there was only actually two times I had to pretty much slow to a crawl and start over.

    Quick question, should I be trying to hit the same RPM range when downshifting as I do upshifting?

    For instance, I know my truck shifts at 1500 upshifting - is that the RPM range I should be aiming for when I rev to downshift as well?

    You guys have been awesome, i really appreciate the advice
     
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  3. jeepskate99

    jeepskate99 Road Train Member

    I drive one at school. Eaton Fuller 9 speed. When downshifting I bring the engine down to about 1300, hit neutral, rev to 1800, and shift. Works everytime. I haven't ground a gear on a downshift yet.
     
  4. rubbergearsnextyear

    rubbergearsnextyear Heavy Load Member

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    Nov 7, 2007
    Lexington, SC
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    You probably shouldn't be making turns in 6th gear. Learn to downshift from sixth to fourth for your turns. 8th is the top gear in a nine speed try downshifting from eighth to seventh at around 45 mph.

    Then try to go to sixth from seventh at around 35 mph from sixth to fifth around 25 mph and fifth to fourth around 18 mph and you really don't need to downshift any lower imo.

    Around 1000 rpms, take out of gear rev up and go down to the next. RPMS aren't always a foolproof method of shifting as you probably know that different loads, weight and terrain seem to have an effect on shifting. You just have to learn the subtleties of your rig.

    I learned in a Freightshaker FLD and a Volvo. Both trucks reacted similarly with the mph and when I went out on the road in the Columbia, it ws just like those two BUT when i got in the Volvo I'm in now, it likes for me to downshift from eighth to seventh around 50 to 55 mph as opposed to 45 as the other three. This truck may be geared a bit differently or it could be because it's the only cummins I've driven so that could be it too. But in general, from seventh on down, they're all about the same.

    Learn how to downshift from eighth all the way down to first without turning the gears into dust and you'll have it down but you will still occasionally rake a gear or three from time to time lol.
     
    Last edited: Jan 15, 2009
  5. D3m3nt3d

    D3m3nt3d Bobtail Member

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    Oct 18, 2008
    Eastern NC
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    Haha I hear ya. The thing is, I dont ever do downshifting from 9th to 8th to 7th etc....because I drive in town I never see the stop coming, just when lights turn red or cars stop etc...I just shift into neutral and coast, then once traffic starts moving - thats where my dilemna begins. I try to guess based off my speed what gear to go into, I guess thats the correct thing to do?

    And I am doing the right thing by trying to shift at the same RPM as the upshift correct? Around 1500

    I was really impressed with my driving today tho, only 3 days and no one to learn from but myself and you guys :biggrin_25519:
     
  6. rubbergearsnextyear

    rubbergearsnextyear Heavy Load Member

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    Nov 7, 2007
    Lexington, SC
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    If you're just barely moving but have a little momentum try 3rd. Revving also works for upshifting. Sometimes you'll go to shift up and maybe not have it high enough just give er a little rev and try again. 6th is a good panic gear if you're moving along a bit.

    On the low side of the tranny I try to upshift somewhere around 1300 and on the high side 15-1600. again it does depend on terrain and load etc. Sometimes ya gotta get it up pretty high.

    It just takes practice and you'll get it.
     
  7. PharmPhail

    PharmPhail Road Train Member

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    Nov 7, 2008
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    Don't do this... it is considered "out of control" of the vehicle. You can coast, just don't put it out of the gear you're in. Brake to the stop, wait for it to lug then put in the clutch. After you're stopped you can take it out of gear.
     
  8. He who is called I am

    He who is called I am Medium Load Member

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    Dec 18, 2008
    Da U P Eh, Michigan
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    Dont forget you can have and eaton 9 speed in a truck and the rpms where you have to shift differ from engine to enginge.
     
  9. D3m3nt3d

    D3m3nt3d Bobtail Member

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    Oct 18, 2008
    Eastern NC
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    Thanks for the advice, I will do that from now on.

    Again thanks to everyone for the help
     
  10. Mighty Mouse

    Mighty Mouse Light Load Member

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    Oct 29, 2008
    Raider Nation, NorCal
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    Yep, I still don't think knowing the MPH will help though because it usually only stays the same in conditions that exactly match where you wrote them down at and doesn't account for how it tightens up when loaded down at various weights or when hauling various types of cargo either (i.e. liquids). The RPMs will be a better tell because they stay the same regardless when shifting. When I started out I tried using an MPH mark per gear as a gage but I quickly found out that it varied +/- as much as 7 MPH of the actual noted MPH depending on some items touched on above, but then I noticed that the gears would only grab and give at only a very particular couple of spots on the RPMs across the board.
     
  11. PharmPhail

    PharmPhail Road Train Member

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    hmm... well the object really is to match RPM's to ground speed, so both factors are just as important. I think what you're experiencing with different load weights or incline and decline is the amount of time you have to make the switch before the speed is wrong for the gear already.

    Typically you must upshift quicker going downhill and slower going uphill, and vice-versa downshifting.

    Either way, all these details prove that there is no substitute for experience.
     
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