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Running in 7th gear on a 9spd

Recently realized I could run all my loads at 50mph no problem I have a 2013 cascadia dd15 8spd I like 48mph, 50mph in 8th has me at 1000rpm and 48mph has me at 1350-1370 in 7th gear is that more fuel efficient and I'm hurting my transmission or engine in anyway shape or form doing this...

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Not sure why you would. All the gears are made from the same material. I run an 18 speed in 16th all the time at normal road speed. Eaton's senior engineer is on record that running in direct like I do, the transmission will run cooler and there is no problem. And let's face it, if you were normally running in 9th and you started working serious hills, you would drop a gear or two anyway, so is yanking that heavy load over a big hill in 7th going to rip up that transmission? Logic would say no. So, I can see no problem with doing what you are doing.

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What about fuel efficiency better or worst?

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Back to the original post, if you are running in direct gear you should be more efficient. Track it for a few weeks to a month with each. As for drive-ability of the truck, 8th seems impractical as that's likely at the bottom or below the power band for the engine.

I'll agree with Jerzy on one point he made, using scangauge or just simply driving the truck based on the boost would improve mileage. Read over this article by Bruce Mallinson on cruise control, http://www.tenfourmagazine.com/PerfZone/...

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Get a scangauge. It's so easy to learn how to drive any truck for its best mpg that "sweet spot" and similar questions are obsolete imo.

I know it's your decision but "safety first". Drving that slow even in a 55mph state is dangerous to you and the traffic around you.

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Heck, driving the speed limit is slow in most areas. And there is no way I am going to run with the flow everywhere.

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I disagree that driving slower is a hazard. I'm with Kevin on this one. Now there is a minimum speed in some states but a car or truck driving slow is not the hazard. It's the people not paying attention to the vehicles in front of them that are the hazard.

Any intelligent person should be able to scan the road in front of them and determine that the vehicle in their lane is travelling at a slower than they are and have plenty of time to change lanes.

I'll keep my money in my pocket and my stress levels down because I wont have to worry about it.

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Dangerous to me Hhmmm ok interesting...speed limit is not a mandate but a limit. Nothing illegal or unsafe about it it's everyone response ability to pay attention to the road. Funny enough I've been doing 50mph for three weeks now and I've had more close encounters with big rigs than four wheelers, which tells me they are the biggest were less group of ppl on the road, too complacent and not paying attention while behind the wheel of the 40ton missle they drive. Id Really like to see how that would stand in court. Ill stay at 50 and keep my 9.0mpg

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So you start of like you're sceptical about your safety and then say you've had a few close ones...which i don't doubt. In court you'll win - if you survive another truck plowing into you - because as long as you're going above the minimum speed limit it's the other guys fault.

And yes, we all need to pay attention but with a speed limit of 65 mph or more it's not common to see someone going so slow. Even though how you drive is legal you may still get a ticket for obstructing traffic (in heavy traffic and depending on cop).

If you run slower on a dedicated route than the fuel savings are worth it because you make the same amount per week but keep more of the money. If you do regular loads than the fuel savings don't come close to what you're losmiles potential extra revenue from running more miles per week.

Think about that and be safe, check your mirrors often in case you may need to react to someone not paying attention (and distractions happen to all of us).

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Lol goodness gracious what have I started second I only run 40 weeks a year and 3200 miles a week same as last year and I already put and extra 26000 extra in my pocket so far. In theory 65 mph truck is not gonna get 7.5 unless your hauling light loads all the time. Your calculation can easily be ripped apart by all the variables one being breakdowns alone on the faster truck. But any ways yes the calculater never dies and yes the faster you go the further you get from you average speed being your goal speed.

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So I ran the obstructing traffic by a friend lawyer of mine and he says it will never stand in court as long as I am in the far right lane exceeding the states posted minimum speed requirement. If I am in the left yes I am subject to fines but if in the left lane to make a left turn soon than no it does not apply.

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Jerzy, first off, there was no need to be rude about it. I'm sure it makes you feel better that you can insult someone's intelligence, or try. Secondly, I know what ergo means, I'm not a simpleton and have actually used it in several of my posts. Thirdly, I check my mirrors very frequently and the carrier I'm leased onto has absolutely nothing to do with anything. They're just who I pull freight for.

My stress levels are lower not because of how often I scan mirrors but because I only work 8-9 hours a day, I take an hour or two lunch break, I'm almost never worrying about my hours, nor do I have to run illegal and I'm able to afford to go home more frequently than if my truck got 1.5mpg less than it does now.

I've already done the math for my operation and going slower puts more money in my pocket for the same amount of miles, simple as that. Your math is correct, if I wanted to run 175k miles a year or more and never see my kids because I'm gone 52 weeks of the year working 70 hours a week I'd obviously make more money. It doesn't take a very smart person to figure that math out, my third grade son could do it.

I have a higher priority than having a p i s s i n g contest over who can drive more miles in a year and it's called being a father to my three children, which to me means being around to spend time with them.

Clearly, you're a Billy Big Rigger who thinks his s h i t doesn't stink based on your post. If you're not capable of scanning ahead an appropriate distance to ensure you don't get stuck behind me, that's your problem not mine. If you have a problem with how fast or slow I drive, pay me the extra money to run my truck at the faster speed, including the increased maintenance costs and I'll gladly let you tell me how fast to run my truck. Until the day you're going to do that, get off it, pay attention and go around me. I'm not breaking any laws, including obstructing traffic, unless I'm out of the far right lane.

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I apologize, got mad because you dropped my score just because of a difference of opinion and not becuase i gave a bad answer. You can run as fast or slow as you like for your numbers but i do think it's not safe. Studies show that traffic is less accident prone when moving at same speed. That said i'm a father as well and i'm glad you can be home more often from fuel savings - i need to put some extra money in the bank from running more to spend home time.

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i'm not trying to convince anyone to run faster but to show that for some it may pay off more.

some variables out of the numbers:

i get 7mpg on every 30 day avg running at 65mph (without working on mpg) pulling a step deck with different sizes and weights all over the country.

according to the slowing down logic if i ran 50mph i should pick up 1.5 mpg, right? (Kevin says .1mpg per 1mph slower)

if i ran only 9 hours each day, only 5 days a week for 40 weeks out of a year (and averaged 62mph for the day from 65 or 49mph from 50)

after fuel the annual gross would be $134946 (from 88200 miles at 49 mph avg, 8.5mpg) or $159588 (from 111600 miles at 62mph avg, 7mpg) at only $2/mile.

at just $1/mile we're looking at $46746 (49mph avg) versus $47988 (62mph avg) annually after fuel.

what if i don't pick up 1.5mpg? that means my profit from running slow will decrease which means that i screwed myself out of money by listening to bad (imo) advice. please, tell me where the holes are in my math and prove that my numbers are wrong.

slowing down for improved mpg works in a dedicated type operation where it is more than unlikely to make any additional revenue per week. that is when cutting any cost puts more money in the pocket but does nothing for the gross. also if you take loads which give you more than plenty of time to deliver do slow down to keep more.

breakdowns...never had one in the 2 years i've had this truck. almost 15 years old with 1.1million miles on truck and motor with no overhaul. but that may just be because of good regular and preventative maintenance.

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okbut what bout these companies that govern trucks at 60-62 mph and we have areas where speeds are 70-80 and even in granny lane we are put in jeapordy at 60-62 mph set trucks and the cars and other trucks come flying up and either push you off road or threaten ya over cb . but i agree running 53 can increase mileage n money 2 pocket.

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And what about those of us that have trucks that run triple digits and yet stay at around 60-62 mph average and do very well? I never feel the angst you do. My truck has never, ever been in the top gear! In 18th at 1600 rpm, I would be turning triple digits. Nope, I just stay in direct drive (16th), cruise along at 60-62 mph with occasional bumps lower and higher as the situation calls for, and I enjoy my 7.5 mpg average for May, 7.62 average for June, and 7.82 average for July. All on pump to pump calculated averages. And I rarely have a problem with traffic and I get everything where it needs to be on time.

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Another point is that when running 50mph or so, you find yourself using shorter routes, many of which are remote with little traffic. I've driven across KS and NM getting 8mpg and not stressed at all. I spend a few more hours behind the wheel, but it pays me to sit. Rather than the old "hurry up and wait" method where we all race like we are NASCAR wannabes and then huddle up at the truckstop and !@#$% about waiting to get unloaded the next day.

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There is a balance between speed and savings. You have to weigh the situation for your operation. There are times when I know I am on my last load for the week and I have plenty of hours so I will run coast to coast at 55mph. Other times I will be under a "hot" load that needs to be delivered ASAP and I negotiate a better rate to run it fast. Another situation is, if I know an an hour or two saved by bumping it up a couple of miles an hour will ensure an extra load for the week, that's what I do. You have to look at all of the variables and decide what is best for you.

I think most of the big fleets have averaged their miles/savings ratios and decided on the 62 benchmark. For a big fleet this may be the best overall speed. An owner operator with one truck can determin on a load by load basis what the best speed is.

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