13 Speed: Probably a stupid question, but...

That's how I do it.

 

And downshifting is opposite, flip, let the rpms drop, once down to 12 or so, you can hear it go loose, gas it and it catches on the up swing..

 

It depends on the year of the transmission.

 

Right. Or a direct. or 6 series overdrive or direct. Like I said, current 13 speed.

Neither single over or direct 13 are produced anymore. 6series small case is long dead, so I tried to keep my explanation simple for the new guys in the "New Driver" form

Correct.

incorrect: 4 speed main box.

Kinda, FR....10s have different case. 15's and 9/13/18 (LLs too) are of the same design main case; designated with R at start of model number. I heard the 10s same as 15s before: not true.

FR was the Fuller designed transmission eaton bought when they bought out Fuller. They continue that designation in the FR transmission who's model number starts out FR (Fuller Roadranger).

R series transmissions are all eaton designed off the FR they bought from Fuller. Most R boxes are about 120lbs heaver and 4-5"s longer then their comparable FR. Basically they beefed up the 5speed box so they could add the 3speed brownie for deep reduction gears and get the 7LL (9speed), 8LL(10speed), 9LL (11speed) and the 15 (12 actual gears that don't overlap).

That trans morphed into the 13 where they use the 3 speed brownie like a 2speed brownie and a overdrive (or underdrive). And the 18 grew from a beefed up 13 that could split the lower ranges.

But then their are 9 speed FR boxes.

And of course there are 10 speed R boxes. Like the 8LL which which shifts like a 9 speed with an added gear making it a 10 speed but is really a 15speed. Then, their was a whole series of 10 speeds that were actually 13 speeds that had the other three gears blocked out so you could shift like a 10 speed. And of course the 10 with the top 2 only shifted like a 13 except for the gears that were block out.

Yup. But based on the 15speed which is like a 5 speed with 3 speed brownie. They just use the same number of cogs differently.

yup

The 4-speed front box contains a lot less rotational inertia then a 5 speed front box and every other shift is with an air cylinder and a synchronizer.

I am happy either way but the U shift was the prior designation for the X shift and it is a real eye opener for someone expecting it and not finding it.

Some old older 13 speeds straight cannot be converted.

Their are lot of rumors on how the new ones can. I have not done one or seen it done so I cannot say one way or the other for sure. But one key with the 18s was they are supposed to contain gears of a higher grade steel and heat treatment that allow the spitter gears to live in a low range split. Weather that is the case with the latest 13s vs 18s, IDK.

Overall since this is in the "new drivers" forum I tried to keep everything simplified so a new guy could start a understanding. But we went there and I just have to follow.

So sorry If I confuse and please refer to my first post if we all make things worse for your understanding. You can still be the winner with 90% of the other drivers at the lunch counter if you know what I first posted.

 

Spits shift you just have to break torque. Eaton insists on the clutch now. Old manuals said either way acceptable. The also insist on not going to neutral. That is is not without reason.

Range shifts must always go through neutral.

 

On a rto 13 spd when shifting, say from 11 to 12th gear, you complete the shift then split to direct as opposed to a rtlo 13 where you would pre select the split then shift? Is this accurate and if it is do you know why?

 

The main thing with all the 13s I've driven is don't pre-select the red switch. You'll wind up with double nothing and will have to completely stop most of the time to get it straightened out.

It's kind of like the old quadraplexes and other two stick models, you never want both sticks to be in neutral at the same time while moving.

 

don't flip the switch until your ready to change.

 

Range has a lockout on it so it won't shift until you're in neutral. The splitter doesn't have that neutral interlock so the moment you hit the button, it'll try to shift. Puts lots of unneccessary wear on the splitter shift fork if you preselect it.

 

No, it's a 3-speed box. If you pull up the manual or the parts breakdown, you'll see it's only a 3 speed.

It's not really a 3 speed brownie, as the splitter and range sections can have independent power paths. A transmission only allows one gear ratio selection at a time, all other ratios are locked out. The aux section allows the splitter and range sections to be shifted independently. It really is two transmissions in a common case (which is itself paired with the main.) Think of it this way, the 13 and 18 have the same number of gears in the aux, but the 13 has three ratios that can be engaged, and the 18 has four.