Converted 9 sp to 13 sp into an 18sp?

converting from a 9 speed to 13 they put a box on the back of the trans plus the shifter knob im not shure if its possible to make it a 18 speed

 

are you really serious ?
a little more than just changing the shifter to get more gears

 

Now I have heard of some of the bigger companies specing trucks with 13--the disabling the top side(or not hooking up at all) which makes it a 9 speed--basically plumb the system to go in the top side of the high side as soon as you shift ranges--and when get ready to trade sell--re plumb system--re install original shifter to sell as a 13 speed-higher resale value--most big companies do not like to spec anything but 8-9(some 10)less possibility of damage due to driver neglect/abuse
So this might be what you are thinking of?

 

Was this a Werner truck at some point? Even if you could, would it really be worth it? If you were doing sitework, oilfield work, heavy haul, etc., I could understand the need for one, but for typical OTR driving? The only real advantage you're going to have is that you'll be able to downshift to the bottom side if you don't remember to pull the splitter back before you downshift, but how often (if ever) would you really use the additional gears on the bottom side?

 

I believe it was an ex Swift lease truck.

KH

 

They actually are selling these convertible 9-speeds to fleets with the idea that a truck with a 13 sells faster and for more money. (Both true) You just pull the back off a 9 and bolt a 13 auxiliary section in it's place.

http://roadranger.com/Roadranger/productssolutions/transmissions/rtoc-16909a/index.htm

You can make a 13 into an 18 by changing the shifter BUT the splitter section of the 13 isn't designed to handle the torque of the lower gears. They are identical in layout, the 18 just has stronger parts; hence the higher torque capacity of the 18's.

 

What about on a 13 speed, when you flip into the high range, instead of going into 5 LOW, you take the shifter all the way over to the left and down where "LOW" is, in the high range isn't that gear usable? Many have argued its not good to use it, while some say the exact opposite.

 

Usable, yes. But not recommended for the same reason: more torque on the splitter. I'll occasionally grab it in town, but only for a brief moment and not under a heavy load. Something in my brain rattling around about that gear not being designed for constant use (i.e., a different gear cut,) or something like that; but I don't remember where that idea comes from, so it may well be untrue.

Also, coming from low range, that ratio is between 3rd and 4th; so if you go there coming up from 4th, it feels like a split down instead of an upshift. I remember in the early 90's Eaton made a 9 speed with a narrow jump between 8th and 9th, the result being you used 5 gears in the high side and only 4 on the bottom. Always reminded me of driving a 'turned around' tranny, and as that was what I'd been running just before that; and for the first week I'd try and come out of 9th and try and get a bigger gear by going up to the dash! OOPS!

 

LOL 1st gear on a 13 speed high range is the goosey gear. Get a surprise when you go there.