Downshifting for a 90 degree turn

Discussion in 'Questions From New Drivers' started by Bones_379, Jul 27, 2012.

  1. jgremlin

    jgremlin Heavy Load Member

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    Apr 21, 2010
    SW Michigan
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    The problem is the answer doesn't just depend on the size of the motor. Its the size of the motor, the gear ratio in the rear and the ratios in the transmission. All of that comes into play to determine when one should downshift and whether that downshift should be a sequential downshift or a skip shift of some sort.

    But the good news is you don't need to worry about it. Because the truck will tell you what it likes and what it doesn't like. The trick (if there is a trick) is to learn to listen to what the truck is telling you and to learn to respect what its telling you rather than trying to force it to do something it doesn't want to do simply because someone on the internet (or elsewhere) told you it should be able to do it.

    Which is to say, just go out and drive it. Try sequential downshifting, try skip downshifting, try skipping multiple gears when downshifting, try it all. Do that and you'll soon figure out what the truck will do and what it won't. Just be aware, that when you get into a different truck, even one with the same or similar engine/trans, things might be different so all bets will be off.
     
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  3. nicholas_jordan

    nicholas_jordan Medium Load Member

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    Mar 31, 2012
    temple texas
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    with 80.000 # you go as slow as it takes, not a tanker is it?....what is the material and trailer?.....with 350 hp & 9-speed it should not be like a splitter on Dana-Spicer, sounds like you may have Eaton-Fuller which will allow you to find the gear where DS wont ... there is no one good gear but I go for 3-4 on a curve I am not familiar with, that is too slow for 55-mph posted limit on standard turn
     
  4. Powder Joints

    Powder Joints Subjective Prognosticator

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    Rosamond, SoCal
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    This is impossible to answer the way the question is ask. Slow down to what you think is safe ten slowdwon so more. You can always spped up next time if your going to slow this time.

    The question the way it was posed is completely a judgement call, and you will get it with experience.

    Remeber to slow down before you try to down shift. Brake first then shift. Drop one gear at a time till you learn how to drive it.
     
  5. WvDiesel

    WvDiesel Bobtail Member

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    Jul 25, 2012
    WV
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    Best way is to do the speed limit, and be at least 5 under if in a straight truck (Dump Truck)! just go slower than the posted speed limit... You will learn as your'e experence grows just take your time and don't get in a hurry!!! You will learn in time how to drive...

    Good Luck
     
  6. MBA Driver

    MBA Driver Bobtail Member

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    Jul 22, 2012
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    Until you become far more familiar with the truck, I wouldn't suggest skipping any gears, and take the turn one or two gears lower than you think is necessary. It takes time to get to know your truck.
     
  7. neal79

    neal79 Medium Load Member

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    Feb 9, 2011
    Chicago,IL
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    I drive a 9 speed and usually go 8-6-4 (8 is highest on a 9 speed, they are counting granny) and usually turn in 4th but if I'm heavy, have a liquid or top heavy load or its a tricky turn I might grab 3rd or 2nd, it all just depends. If I'm heavy I also might grab all the gears on the way down for more braking, it takes me less than a second to down shift so its not that hard to grab em, so really every situation is a little different but you can never go wrong with going too slow or in too low a gear until you know the truck better.
     
  8. chompi

    chompi Road Train Member

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    Jun 21, 2008
    Deland, FL
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    Never shift down to first or even second or third. Most trucks won't let you go to first or second unless you are stopped anyway. Corners speeds in a 9 -10 speed truck are usually 4-5. Some say to be in gear before, some say during, I say whatever you are comfortable with and depending on the situation. If its a tight corner or there is traffic involved occasionally you will have to stop, letting traffic rearrange so you can get through.

    Always remember that first through fifth gear are your parking lot speeds and should carry you up to 25-30 at the most. You rarely use first unless you are loaded heavy or on a hill or something. You can usually start off in second gear when loaded and third when empty. You may also "skip" shift when you are empty. When skip shifting keep in mind it only works through gears 1-6 and you must allow more time for the rpms to drop before putting in gear. You can skip shift any gear going down, you just have to match your speed to gear and the lower the gear and higher the speed the more you must rev up your rpms before dropping in the next lower gear.

    Practice makes perfect! Learn to float while you are doing this and it will also make life a lot easier. Whatever you do keep in mind that you should never hear a loud grind. There is no reason for it. Shift with the tips of your fingers and if it doesn't just slide in then don't force it. Figure out what needs to be done to get in the hole with ease. The sooner your practice and pay attention to refined driving the better driver you will be and the faster you will learn. Number one thing to remember while shifting is not to get nervous or flake when you miss a gear or can't get it in the hole. Think to yourself about the situation at hand, "what speed am I going" "uphill, downhill etc..." If you are doing less than 30 then you know most likely will be 4-5 gear. If almost stopped or at a slow roll then 3. Forget about 1-2 unless you are stopped. If cruising above speeds of 30 then use 6-10. Tenth gear however is usually just an overdrive gear so now you have narrowed it down to 6-9. If you are above 55-60 then use ninth gear. 30-40 use 6-7. 40-50,55 use 7 or 8.

    If you are a really new driver get a dry erase marker and draw your gear pattern right in the center of the windshield so you know your shifting pattern. Once you start to get good you will be able to do this all by ear.

    Like I said its all practice and confidence in yourself.

    Good luck hope this helps you out....
     
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  9. JunkHauler

    JunkHauler Light Load Member

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    Jan 6, 2010
    Hamersville, OH
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    A good idea that was taught to me as a kid was to watch the speedometer while you are upshifting and figure out what speed and rpm range each gear levels out in and then you will know what gear to downshift into. It has always worked for me regardless of the truck.
     
  10. Ezrider_48501

    Ezrider_48501 Road Train Member

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    bismarck, nd
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    this is very bad advice and scary to think someone drives like this on the road.

    take it slow start slowing down way before your turn, do not be worried about slowing traffic behind you they can wait. practice taking one gear at a time learn your rpm difference between gears if you end up getting your rpms real low just grab two gears. biggest thing is take your time don't let anyone rush you.
     
  11. windsmith

    windsmith Road Train Member

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    NEPA
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    That's funny, that advice came straight from my CDL instructors - each with 30+ years of driving experience. What makes you say it's bad advice, other than that it's being passed along by someone with less than one year of experience?
     
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