The Road Ranger - A Dodge Ram W350 12valve with an RTO610 transmission!

Finally a Dodge with a proper transmission

To anyone wondering about the history behind these “baby Road-Ranger” transmissions with the shifter mounted air button operated cointershaft brake, I’ll share what I know about these interesting units. These were the “baby 10/13 speeds”, models RT(O) 610, 613, 6610 and 6613. They all use the same housing and the same parts in the 5 speed “front section”. The difference in the “66” series and the regular “6” is the 66’s use bevel cut gears in the timed, air shifted “back / range box” for quieter, smoother operation over the straight cut gears in the 610 and 613. The “13” speed models in this series were extremely unique as they were actually a 15 speed in design because they used the 610/6610 10 speed box with a deep reduction auxiliary section on the back…..but unlike all the other “15 speeds” these were actually named accurately. All 15 speeds are built on the same formula (10 speed main box with deep reduction added) but they don’t actually offer 15 non-repeating forward gears. Shifting sequentially a 15 speed only has 13 unique forward ratios you can use, the last 2 deep reduction gears are actually slower than the lowest two “regular” gears. The shift pattern for the 613/6613 is actually the pattern you use in all the 15 speeds to get from the lowest gear to high without shifting down again. Of course all the other “13 speeds”also offer 13 unique forward gears as well but they do it a different way, giving 5 gears in low range and 8 in high by using a a “splitter” type auxiliary section in the high range gears…..All the other 13’s (along with and 8LL and 18 speed) are built on the 9 speed main box, but they didn’t make a 9 speed as small as the 6/66 series making the baby 10 and 13 “one-off” models with no replacement after they stopped production. They are (conservatively) rated for 600 ft-lbs of input torque and were actually pretty common in medium duty trucks with air brakes from the late 60’s up to the 80’s…..they basically replaced the “twin stick” 4/5 x 3/4 transmissions common in the higher GVW “medium duty” model trucks at the time and were a common retrofit to these trucks as well. The most common application I’ve seen them in is Ford L700(0)/800(0)’s with the 534 Gas, 3208 or 8.2 Detroit but they were popular in similarly sized and powered IH and GM trucks as well.

Besides the Diesel engine of course the road ranger transmission is the single greatest invention to come to the trucking industry in my opinion. Easy to service very strong many different options to suit whatever the need may be. Engineering at its finest

Second thing. I love that it’s not just about one person. We get a feel for the amazing amount of talent that’s out there.

I had a 75 ford f250 with a Perkins 6 cyc and a RT610. I loved that truck, nice thing about the road ranger trans is it only has 400 rpm drop between gears. Mine had a 16 in clutch, and a flywheel from a c60 truck.

This is the most bad ass set up in a pick up I have ever seen.

"some games we just don't play" gotta love it

Hats off to you! You can pull as much as you are comfortable with, without killing the engine. I have wanted to do this to my 2009 Chevy dually with a tired 6.0 gas and a 6l80e auto… Cummins and a 10 speed swap

Used to herd tandems with 3208's and 466's and all had 13-unders with the countershaft brake. Used just for getting it in gear or either scrubbing for a week while waiting or just shut the diesel off and yank it. A 13-under has it all. Moved a 20 ton track loader on a 20 ton rated tilt top trailer and never missed a lick here in the hills. Always wanted a G.I. 5-ton with a 10-speed. Herded a Pete tri-axle with a 3406 and empty went from lo-3rd, lo-5th, hi-3rd, hi-5th. Never did know what a load was. Blessings!

What? No 18 speed transmission, a real man's transmission. Seriously, a 10 speed beats anything the small truck manufacturers offer.

A I am no mechanic at all but I am in awe at how you guys do this stuff . I am a carpenter / builder by trade but am always blown away at builds like this as engineering / mechanical is all witchcraft to me but I appreciate the skill and knowlege that goes into this kind of bespoke work !! 👏👏👏

Well done interview! Appreciate you sharing the info on what was involved in the upgrade!! SWEET RIDE !!

Man this truck brings back such memories! I grew up on the farm and my Grandpa had an all red non dually 12 valve.... and had the same color interior...It was an automatic though... That truck took a beating! I mean it worked HARD its whole life.... Well the engine out ran the body... The body and frame were so rotted out from rust .. It was a Michigan truck.. But the day she left she RAN like a dream! Had them adjustable bands in the transmission .

I was working as a machinist thru highschool. We had some old gas burner trucks with 2 speed rears. At the time I knew where I could have gotten a couple Road Rangers. Everyone said they would suck up too much power from from our old trucks turning all that gear mass. I knew machining the adapters wouldn't be any trouble, but didn't wanna do the work , if it would use up too much of the power of our old 292 inline sixes , or the 350 small blocks. I know a stock 12 valve has enough zap for about any person for everyday abuse. Have y'all noticed any draw from the power it was putting through the slushamatic??? I'm retired now , and still have an old 65 C60 Chevrolet the little 292 has plenty of power , if you keep it in it's happy place or RPMs. A 10 - 13 - 18 speed would be so much easier and faster between shifts than the Old 2 speed rear end. I kept this truck , because it pulls as well as any of the small block V8s , plus it only sips gas compared to even the 283 , or 327 V8s. I wanna make this old girl into a camper puller. I just don't wanna do the work , and expenses if it'll kill the power. But this is a subject that I've pondered for well over 40 years

Now that’s a real transmission, all ya need now is a Thunderbrake jake.

Hi James good to see this video on your truck thanks Zig

What's nice is gear vendors makes a kit for the manual transmissions in pickup trucks so you can split all non granny gears so you can do this with less work now

York 210 is a great air compressor also. I have a old 10 gallon air tank strapped where the spare tire was. 😊

That's one sweet 93! Makes me miss mine.

wow thats a lot of work! my 12 valves got a fso5306. luckily ford did all the math for me and everything bolted up