RTO vs RTLO

There is some difference but I wouldn't say it's hard to shift. After you round off the gears and get some slop in the shifter it'll be easier

 

I'm a mechanic, not a driver, so I am far from a pro shifter. We only have 2 trucks with RTO's and the other 25 have RTLO's. 99% of the time I only drive them in/out of the shop and around the yard, rarely getting out of 3rd gear.

I hate the RTO's, I miss more shifts with those 2 trucks than all other trucks combined. When I do actually road test them, it doesn't take long to get used to them, so I say they are harder to shift, but not really hard. It's just takes a few miles to get used to the difference. I think the biggest difference is getting them out of gear, any bit of pressure on the gears causes them to hang up, where the RTLO's are not too picky. When you let off the throttle and push/pull it out of gear, there is a smaller window as the when they will actually come out of gear easily. Only seems to be an issue in the lower gears, the ones I use the most.

 

I will revive this thread. I'm running a RTO 15613 with 402's 3:36 rear. Cat engine has been revive with a 550 BS file and tweak fls/fts with 58's. My plan was to replace the or upgrade the trans to RTLO series eventually, well the time has arrive. But the upgrade core charge is rediculous. Not to mentioned the 189 series has the same input shaft number. I have a set of 402's with 3:70's I bought from a buddy, housing and all and was going to drop those in with a RTLO but after doing research and talking to people, I would be losing about a gear or half with that set up I had planned(RTLO with 3:70) compare to my set up now(RTO with 3:36). Any thoughts, please feel free....

 

The RTO has the aux gear splined to the shaft where the RTLO has the aux gear set on a slide collar. The RTO 613 has a final ratio of .78 with overdrive being run thru the aux box causing lots more heat.

The RTLO 913 series has a final ratio of .73. It's set up totally different. It's overdrive is in the front box. The aux box is actually an under drive set up. When the splitter is in direct the aux box is turning to reduce the ratio of the gear instead of increase. When the button is in the overdrive position the aux section is unapplied. It works opposite of what you would actually think. That allows less heat as well as rolling mass.

I think you would be fine with the 3.36 rears you have the way your set up is described, I don't think though if you go to 3.70's you will loose any road speed.

 

@wore out, thanks for the explanation. Now I understand the difference between the 2. I run locally and usually run in direct here in Cali the state of 55 mph. I do use OD quite a bit but don't stay in it very long period. Like I said above, the difference in the upgrade core charge I think isn't worth switching to a RTLO($2500.00) plus the transmission another $3300.00.
The synchros in my current RTO15613 have been gradually going out(grinds when splitting low to high) and has been doing this since I bought the truck 8 years ago. Also the clutch can't be adjusted any more, time to replace it so I might as well do it all, clutch, trans, rear main seal, and gasket seal between engine and bell housing(started to leak) and motor mounts.

 

Tap the clutch to break torque and it slips out of gear smoothly.