Diff lock vs inter axle lock

Discussion in 'Experienced Truckers' Advice' started by Air Cooled, Jan 13, 2017.

  1. truck_guy

    truck_guy Medium Load Member

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    Like, actual smoke. The smell of burning gear oil is unforgettable. Both times were after a few hundred miles of driving with the power divider locked.
     
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  3. TripleSix

    TripleSix God of Roads

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    You're rolling down the highway at 50 mph. You have a hill in front of you that's shaded and you see ice and snow on the road. While rolling, lift off the throttle, engage the inter axle, back on the throttle. You keep your momentum going. All you have to do to make sure that nothing is damaged while engaging the inter axle is make sure that the wheels are not spinning at different speeds. If you are rolling at 50 mph and you let off the throttle, there's no way the wheels can be spinning at different speeds so it is perfectly safe to engage the inter axle.


    NOW, you're running down a gravel road. You see a 13%grade with gravel. Stop. Engage the inter axle. Engage the diff lock. Pick a gear that you can stay in that you can pull that hill without shifting. Same principle goes for deep mud. You're going to have to use the low gears of the transmission to walk that load up the grade without spinning or stopping. Mr Lepton alluded to this in an earlier post. Off-road is completely different than on the road.

    EDIT: We had one of those YouTube video guys express interest in switching to open deck. Unfortunately, one of the guys saw a link of him trying to get up a steep gravel grade by gunning it and trying to use momentum to get him. It doesn't work. It DIDN'T work. He stalls the truck on a hill, and tries to get started again by revving the motor and dumping the clutch. He didn't break anything, but the truck shuddered and bucked and stalled out. This video as posted into a forum full of heavyhaulers and gearheads, and they unloaded on the guy (if you didn't know, heavyhaulers and gearheads get belligerent when they see trucks getting abused).

    Anyways, I asked the YouTuber (who was obviously a rookie...most of them are) if he wanted to learn proper procedure (he never responded...maybe he didn't think he was a rookie, but if he wasn't why in the heck would he rev the engine and dump the clutch on a grade, if he wasn't?)

    Smooth is fast. Level ground, pick a gear that you know for a certainty can pull the grade with the weight and let the gears walk that load up the hill. No engine revving, no banging, just a slow walk up and over the hill.
     
    Last edited: Jan 16, 2017
  4. not4hire

    not4hire Road Train Member

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    Just a couple more points I would add. I don't let off the throttle completely and I shut off the jake momentarily if I think I am already on a poor-traction surface, such as ice. You can get wheel-lockup from engine braking which is just as bad as wheel-spin when engaging inter-axle or differential locks.

    Because I did a lot of off-road driving and pickups/deliveries in gnarly areas; my rule was, as soon as I was turning off the pavement I engaged the inter-axle (if it wasn't already in--which it probably was in the winter).

    Lastly, if your truck has traction control there should be a switch to disengage it. It might be labelled "traction" or "off road" or something similar. If you get to the point where you have both inter-axle and diff locks engaged, you should disengage the traction control, especially if you are getting into mud or deep snow. In either of those last two conditions you need a little bit of wheel spin to keep moving... not a lot, you don't need the speedometer showing 40 when the truck is doing 4. Just enough to keep moving forward. If you wait to disengage the traction control (or to engage the locks) until you're in the situation... it's too late.
     
  5. TripleSix

    TripleSix God of Roads

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    Understood. I will shift the inter axle like I shift gears. The jake is a tool that I use as needed. It would already be off. I click it on when I need it and as soon as I don't, I shut it off. I used to leave mine on all the time, but the problem I found was that some times at the absolute worst moment, the jake would come on and make the tractor squirrelly. For me, it was a bad habit that almost caused me to jackknife.

    You will often hear about me talk about bringing the A Game every time you play. We all goof, right? Even A Gamers. The A Gamer will instantly make adjustments so that he doesn't repeat that goof. The people that don't make adjustments to their game have wreck, after wreck, after wreck.

    By the way, I find your post fascinating. You are explaining your science of driving. Never had traction control in a truck, but quite a few in sportscars. I understand how it works and why it wouldn't in a mud bog.
     
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  6. AModelCat

    AModelCat Road Train Member

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    Quoted post deleted.

    I don't like how close he is to the edge of the road all the time. If its clear, I like to be out towards the middle (and away from the potentially soft shoulder). That's a rollover waiting to happen IMO.
     
    Last edited by a moderator: Jan 16, 2017
  7. TripleSix

    TripleSix God of Roads

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    Good point.
    Question: Why do you think he does that?
     
  8. Ruthless

    Ruthless Road Train Member

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    But he
    "Ain't been trained in this type of environment!"

    Lol

    Man, @TripleSix i hadn't actually watched past the first 30 seconds or so the first time round because of that voice and "ITS A FEMALE FLATBEDDER! I AINT EVER SEEN ONE OF THOSE!"
    ~really?~

    I made it further this time; still not all the way thru
     
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  9. AModelCat

    AModelCat Road Train Member

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    Couldn't tell you. Lack of training, lack of common sense, not being encouraged to think outside the box as a child?
     
  10. TripleSix

    TripleSix God of Roads

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    ROFL! To be honest, I haven't either.

    You're a classical guy like me. Have you ever seen the play, "Pygmalion"? About how a professor of phonetics makes a bet that he could teach a homeless girl how to speak and behave well enough to pass as royalty in high society England? If you've ever seen the play, the girl lives on the streets, is dirty, and speaks with this nerve grating voice. The girl wanted to better her life and she went in, studied and learned and was thought by many to be a princess.

    Well, the same goes with Mr Jackson. If he had wanted to learn, I would have helped him. I like to see young drivers who are good at their craft. I do understand why he didn't return...but you just cant abuse the equipment around heavyhaulers and gearheads...they unloaded on him.
     
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  11. TripleSix

    TripleSix God of Roads

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    When the video starts, he's on asphalt. When he gets on gravel, he tries to drive the same way as he does on asphalt. No adjustment for his terrain (Defensive Driving 101).

    You're leaving the mall. The mall is closing. The parking lot is nearly empty. You notice a guy leaning against the outside wall as you walk out the door. He starts moving parallel to you. Do you make any adjustments?
     
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