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Need to be schooled in Big rig driving...


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Well Gang... Our local fire department purchased 4,000 gallon water tender. It's a 1984 Kenworth Water Truck. It's got a Eaton/Fuller 9 speed transmission. So far I got a quick lesson from one of my fire fighter in my station. I've mastered the up shifting just fine but down shifting I tend to get stuck. So maybe there is a few gents here that done some big rigs that can school me up on shifting this beast. I got to admit its a wonderful water truck (Cummins Big Cam 400) it climbs steep mountain grades with a full load water without even struggling. I've just spent 2 days driving it around loading water tanks.So could some one give me some pointers... This is what I found...

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First of all, that is some classic cinema right there. Also, I don't know any truckers that bother with the clutch outside of starting and stopping. The RPMs have to match whether using the clutch or not so its easier to not. On the 18 speed I drive I'll usually pull it out around 13-1400 and it drops right in to the next gear. I don't increase the RPM I up shift at like the video said. Same shift point all the way up. And what he said about kid gloves is right on; if you have to give it any more than finger pressure you're just gonna break something. It should just drop right in shifting up and down.Downshifting is the opposite of upshifting. Let the RPMs come down, pull it out of gear, rev up to match gear speeds, and drop it in. This is where you have to learn the feel of your specific truck. On the 18 speed a hard downshift will drop in around 1800 and come out about 1500. With the Jake on full blast that'll slow you down in a hurry. A gentler downshift would be to let it come down to 1200 and rev up to 1500 to get back in the next gear down. But like I said, your truck will likely shift different. You just have to learn to listen to the RPMs and get that muscle memory in your foot of how much movement it takes to get those 300 revs. Practice, practice, and practice!:thumbup2:Hope that was helpful.

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Yeah... I called a friend last night in Louisiana (Towhungerford) and asked him as well. Told me the same thing. Just use the clutch for starting and stopping the truck. From there on out forget that clutch is there. Even he suggested against double clutching and suggest floating all gears.It seem there is going to be maybe 3-4 people capable of driving this truck. :duh:Well at least its a Cummins and I've got no problem driving one of those... :cool::cummins:

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I can't tell you much about driving the truck since I only ever get to the high side on test drives after a trans rebuild but at work we have a 86' peterbilt milk truck with the 400 big cam and a eaton 9 speed that we use as a backup truck in case one of the other milk trucks go down.

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You can practice in your truck.. When my clutch blew all the springs up it was just engaged the whole time. I was at a stop sign and it just broke instantly so it took off but happened so fast that it just stalled before I hit the car in front of me. I just started it in 1st and drove it like a semi all the way home. It actually works a lot better in 24V's because they drop RPM so slow you can easily hit the sync speed. When you push the clutch in on mine the RPM drops like a rock and you hardly have a chance to get it in before you missed it so you gotta play with the pedal a little.

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Yup, clutches are for starting and stopping. And passing a CDL test, I hear. If I ever do that I'll have to find an auto to test in. Double clutching has never made any sense at all to me.

Tapatalking in traffic

Actually, the DMV lady in my county said Montana isn't currently requiring double clutching on the CDL test. Not sure how long it'll last; regs change all the time. But I thought it was cool they realized no one really does that.

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Careful playing with floating gears in something with synchros. It's a quick way to commit yourself to matching revs on that gear until you drop the tranny and put some fresh brass in it. Tapatalking in traffic

I always wondered about that but never heard anyone come out and say it. Now I know why you have to sync my brothers powerstroke. He does nothing but drive like that.
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I've heard that too about floating a sync'ed trans. But also heard of several people floating gears and doing it for a very long time without problems. But I tend to agree with Mr Mindless that being Dodge installed the clutch and syncro's it best to shift using the clutch as designed. Like myself I've floated a few gears in my time in my truck but don't make a habit out of it.

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Most have hit on not double clutching but I had to do it when I got my CDL many years ago as ND DOT requires it while taking the driving test.Every truck is a bit different but once you figure out the feel it only takes a little bit to feel out the differences. If only running one truck it will catch on pretty quick and even easier with a 9 speed, when you get into the 13-18+ speed rigs it takes a bit more practice.The trick is to watch the tach and do not over rev things, slow and easy is the best, get to know what rpms it will slip into gear going up and down the easiest and like pointed out before every engine drops and accels at different rates and this needs to be figured in too.If you ever drove a Detroit diesel you know what is is like to speed shift, they drop rpms so fast you have to stab gears as fast as you can, good thing they are about extinct so most will never get to experience this, I learned to drive semi as a teen on our family farm in a 1970 IH with a straight piped 6-71 Detroit with a 10 speed and no power steering.:banghead:When I worked at a truck shop for a few years there were days when I would have to test drive several different trucks so you learn to catch on pretty fast.

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I love detroits. I don't know why, but I do. We were phasing out the 6V71s when I started in oil & gas, and those trucks lugged around the leakiest noisiest 12 and 16V71s ever.

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Be aware there might be a clutch brake.. so when clutch is fully depressed, a brake will come into contact with the clutch disk! (that makes it almost impossible to shift w/o buzzing the gears)... but it sure speeds up stopping the disk to engage from neutral. (and holding the truck on a hill whilst stopped) 3 legs no longer needed~ I had a heck of a time before I realized pressing the clutch harder made it worse! If yours does, find the sweet spot in the middle!

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You know the worst part about being in a vehicle where you have to float the gears because the clutch is trashed, is to everyone else, you look like an idiot trying to learn how to drive a stick...especially at stop signs where you have to shut the vehicle off, and restart it in 1st gear until it starts rolling!:lmao2:

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Yup, clutches are for starting and stopping. And passing a CDL test, I hear. If I ever do that I'll have to find an auto to test in. Double clutching has never made any sense at all to me.

Tapatalking in traffic

Even using an autoshift might not be helpful. I keep hearing about a proposed law that if you take a CDL test in an autoshift you are limited to driving only an autoshift.

- - - Updated - - -

Be aware there might be a clutch brake.. so when clutch is fully depressed, a brake will come into contact with the clutch disk! (that makes it almost impossible to shift w/o buzzing the gears)... but it sure speeds up stopping the disk to engage from neutral. (and holding the truck on a hill whilst stopped) 3 legs no longer needed~ I had a heck of a time before I realized pressing the clutch harder made it worse! If yours does, find the sweet spot in the middle!

You also need to be aware of what type of clutch brake there is installed. There is a one piece design and a two piece design. If you hit the clutch brake while shifting gears going down the road with a two piece design you can very easily snap off the bolts/roll pins used to hold the halves together, then you have no clutch brake. If this happens there is also the risk of taking some chunks out of the input shaft. Have had to replace quite a few input shafts in fuller transmissions from a two piece clutch brake being used incorrectly. DO NOT trust the clutch brake to hold the truck in any situation, there is very little braking surface and it was NEVER intended for that purpose.
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Your best bet would be to go to a driving school

That would be optimal but I'm not going to pay for it though. I really doubt the fire dept will pay for it either. Idaho law states that fire dept are exempt from the CDL requirement. I drive several other large and heavy trucks without a issue. My only issue is working with a 9 speed trans. All of our other trucks are automatics put in DRIVE and stomp the throttle.
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NINE speed is the easiest tranny to learn on as you do not have any gear splits just high and low range, take the same 9 speed and change out the tail section to get a 13 speed and then you can split all the gears in high range.A 9 speed is a lot easier than a truck with a straight 4-5 speed and a 2-speed rear end, those were always a pain to drive.

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Your best bet would be to go to a driving school

http://www.itd.idaho.gov/dmv/driverservices/CDL.htm

Exemptions from CDL Requirements

Even if your vehicle is a commercial vehicle according to the definition above, you may qualify for one of the CDL exemptions. There are four categories of CDL exemptions.

Recreational vehicle exemption - applies to drivers of vehicles used exclusively to transport personal possessions or family members for non-business or recreational purposes.

Military vehicle exemption - applies to military vehicle operators who are considered active-duty military personnel and to civilians who are required to wear uniforms and are subject to the Code of Military Justice.

Emergency vehicle exemption - applies to drivers of firefighting or other emergency equipment used in response to emergencies involving the preservation of life or property.

Farm vehicle exemption - applies to drivers of farm vehicles, including family members and farm hands, under certain conditions only. The farm exemption applies to drivers of farm vehicles which are:

[*]Controlled and operated by the farmer,

[*]Used to transport agricultural products, supplies, and machinery to or from a farm,

[*]Not used in common or contract carrier operations, and

[*]Not driven more than 150 miles ("as the crow flies") from the farm.

The farm exemption is intended for small farm-to-market operations only. Unless Idaho is involved in a reciprocity agreement with the other state(s), the farm exemption does not extend beyond the boundaries of Idaho. It does not include farmers who are transporting other farmers' products if they are receiving any compensation for the services.

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