Why 13 speed better than 10 speed manual

OK, the 13 speed gives a couple more steps along the way. What really matters is if the 10 speed or 13 speed are direct drive in the top gear or overdrive, or in a lot of 13 speeds, double overdrive. A 13 speed takes a couple more horsepower to operate as it has more gears moving all the time. The best way to have it is a 13 speed double overdrive, then 11th is a direct gear, match the rear differentials to drive in direct and you will have a more efficient set up. That way running mty or lightly loaded, you can idle along in an overdrive gear. Many mega carriers used to use the 10 speed, now they have mostly gone to automatics.

 

Think of it this way...you bought a new fridge, and you live in a place with a front staircase and a back staircase. Both go up one floor, but the back staircase has more steps, but each step is a half the size of a normal step. When climbing steps with a heavy load, if each step of that staircase is half as big as a normal set of stairs, it makes the climb easier on your legs with the load because they don't have to lift as far per step...but, if you're going up the stairs empty...you can skip steps. That's why a lot of heavy haul drivers have trucks with an 18 speed. In general freight, if you don't spend a lot of time pulling heavy loads in the mountains, then a 10 is fine. But if you do pull heavy loads in the mountains, a 13 or 18 is better because it keeps your engine in it's power band a lot more of the time so you don't drop as much speed.

 

Flat ground runs at regular weights with good power a 10 is fine. The 13 or 18 are great for pulling overweight and running in hills.

Climb 6 miles up a mountain pass, and back down the 7% grade one time with both, and you'll see the value.

Think of it as a 10 speed, with an extra gear in between all of your high side gears.

 

I never liked 10 speed transmissions. The rpms between gears would drop too much when climbing hills for example. Say you are climbing a 6% grade, winding up the rpms in anticipation of upshifting, when you do the rpms fall flat on their face and it takes a while to get back into the power band again. 13/18 speed, you're just upshifting "half" a gear at a time and staying closer to that power band.

 

I just moved into a new truck this spring, with an 18 speed. Last truck had a 10 speed.

I want my old one back.

For what we do, the 10 speed is more than sufficient, provided the horsepower is there, and in our trucks, that's not a problem. With the hills around here, and the power we have under the hood, that half a gear downshift in a 13 or 18 speed on a hill doesn't save anything, because if the hill is big enough or steep enough that we have to drop gears, you're needing a whole gear anyway.

Some will argue (and I have tried this argument myself) that more gears give you more options on hills, and thus better fuel economy. It's hogwash. I got better mileage with the 10 speed. Literally everything else on the trucks are identical, except the transmission.

If we were hauling something heavier, surely I'd have a different opinion. But at 80k gross, we have no need for the extra gears.

I shake my head anymore when I see a used truck advertised for sale. Usually says something along the lines of "ELD exempt, pre emissions Pete 379. 550 Cat, 18 speed, 3.73 rears. Has 1.4 million on the clock, rebuilt 200k miles ago, blah blah blah". Usually asking a small fortune for it.

I shake my head because I know most people that would buy such a truck aren't hauling Cat D9 dozers out of a forest with it. They're hauling general freight on the interstate. And hey, if that's what they want, who am I to judge? But it's overkill for most operations. That's not a combination to be hauling general freight, so the fuel economy is gonna suffer. But hey, they can run up a hill like they're in the Pike's Peak hill climb!

 

I've never actually seen a truck with a 9, 10 or 13 speed. They've all been 18 except the one 15 speed I own.

 

For what you do, they may be fine, but I'd bet 10:1 that the O/O's I've dealt with over the last 27 years would take a 13 over a 10 100%. Maybe not many except the heavy haul would use the 18, but I guarantee if for some reason you unfortunately have to stop uphill on a 7% grade, and you can't pull out with anything but low gear, that 18 is the difference between gaining gears, and maintaining low.

 

Yes, for what WE do, and probably 90% of every other driver (company or OO), the 10 speed is fine. Low gear is low enough that anyone worth his salt ( becoming rare nowadays) would get going from a stop on a steep hill.

The 13 is a great transmission, I've run them, and it's actually what I prefer over anything. I wouldn't argue that most OO's would take one over a 10 every time. But, it's a luxury more so than anything. And nothing wrong with that.

The 18 is in a league of its own. For heavy haulers, it's the ONLY way I'd go. But again, for most operations, it's kind of pointless.

 

The thing that makes this amusing is the people who say I want my 10 speed back, or a 18 is overkill, or 13 is not needed. Well it's better to have and not need then the other way around. If you want you 10 speed back then just straight shift your 18. You don't have to use the splitter ya know! In my honest opinion the 18 speed is the most versatile trans ever made. It's a 10 speed, 13 speed and 18 speed all in one.

And don't get me going on wieght, because isn't even worth talking about.