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Upshifts with engine brake

Discussion in 'Trucks' started by Don.S, May 31, 2019.

  1. Don.S

    Don.S Well-Known Member

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    So I recently got my licence to drive truck and have been driving a 94 international dump truck with a 3176b and a 8ll. I have found when starting on a hill and loaded I have a difficult time shifting from low to 1st and 1st to 2nd. I have been using the engine brake to bring the engine speed down faster and it works well but I have now told that doing this is bad for the truck.
    Is there any truth behind this or what?
     
  2. TVA

    TVA Senior Member

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    IDK but I used to have a truck with Meritor ESS system. That thing would rev. Engine by it self when downshifting and put Jakes for split second when upshifting constantly. N14 safely got to almost 1 000 000 miles and was in framed, and that Rockwell 10 speed has almost 2 000 000 on it, noisy as hell - but still drives.
     
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  3. Birken Vogt

    Birken Vogt Charter Member

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    I don't see how a few blaps on the exhaust valve could hurt anything more than blapping all the way down cabbage hill but maybe there is something I don't know. I agree the autoshift systems sometimes use them so I guess it is OK for them.
     
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  4. RZucker

    RZucker Senior Member

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    It's just fine as long as you get it right and don't shock the drive train. As mentioned above the auto shifters use the jake at times. Just be smooth.
     
  5. Labparamour

    Labparamour Senior Member

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    Yeah, I’ve used the “low” Jake setting or sometimes switch engine fan to manual when starting out- that pulls engine speed down pretty quick.
     
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  6. heymccall

    heymccall Senior Member

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    My PX7 w/ 8LL is the same way. If I don't put the fan clutch in on a hill start, I can never get the 2-3 shift.
     
  7. Jonas302

    Jonas302 Senior Member

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    Cant see how its possible for the engine brake to be hard on the engine most of our guys leave them on all the time
    I have the same trouble with the 8ll I try to avoid low unless really needed as in soft ground or uphill the truck has usually came to a complete stop before you get 1st
     
  8. td25c

    td25c Senior Member

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    We usually just put it in the gear needed at the time & ride it until the governor pegs out . :D

     
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  9. DMiller

    DMiller Senior Member

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    Sometimes just better off to let her set on the governor and deal with the slow speed.
     
  10. Pipevine

    Pipevine Active Member

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    I leave mine on all ONCE THE ENGINE IS FULLY WARMED UP. Just like any hydraulic system, it's best to get the oil up to temp before Putting under load.
     
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  11. Birken Vogt

    Birken Vogt Charter Member

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    Some throttle pedal setups make it easier to leave on than others. Some have a pretty big dead band between Jake on and where it begins to put fuel to the engine. Others seem to just barely come to idle when the Jakes come on. If it is the kind with the dead band I pretty much leave it on all the time but the other kind has you reaching up to the dash to switch it on and off constantly.
     
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  12. dieseldog5.9

    dieseldog5.9 Well-Known Member

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    I am not trained as a driver, I am trained as a wrench, however I do not shift on the jake, i progressively shift so in lower gears I don't bring the engine rpm up very high, in second bring it up a little higher. Search YouTube for progressively shifting a truck. This can be difficult pulling from a stop light with ten cars behind you and ther is public pressure not to hold up traffic. A lot of young truck drivers hauling logs and chips here rev the engine up and blat the jake every gear from the main light in town, and I see some old time drivers you could balance a coffee on the hood of the truck when they take off from the same light. I think it is harder on the truck all around to wind it up and jake it every gear. A guy I respect as a driver has a 12 speed Mack he swears by jake shifting. I shut my jake off until I need it then shut it off. Also look on YouTube for videos from smart trucking, he seems to be a professional driver. Remember as a professional driver you are like the captain of a ship and the investment of that truck and its condition is your responsibility to look after. My .02$
     
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  13. DMiller

    DMiller Senior Member

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    When owned the K100 8V92 would nestle a toe close to the clutch pedal, leave jakes on just gingerly touch the clutch and keep it from engaging the jake. had enough free pedal to do that and not encourage throwout bearing degradation.
     
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  14. dieseldog5.9

    dieseldog5.9 Well-Known Member

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    Guy who taught me to drive told me he would break my f&$@ing leg if he caught me with my foot hovering on the clutch pedal between shifts and I think he meant it. There's a video of mr spooner of spooner trucking discribing how his mentor would rap his knuckles with a ruler if he did such a thing.

    On the flip side another old timer told me to slam my hand in the door before driving a 2 stroke and drive it like you were pissed off at it, it liked it.
     
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  15. RZucker

    RZucker Senior Member

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    Being a long time 2 stroke guy... We called it "Run it like you stole it" :D
     
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  16. DMiller

    DMiller Senior Member

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    Can relate to both of the Latter, the guy that taught me to shift a Fuller was old school, carried a fiberglass antenna rod, was quick and accurate with it, taught me similar on adjusted RPM shifting lower gears some higher others just quicker from one to the other. And in a Freightliner 8664 COE with 8V71 against a RTOO9513.