13 Speed roadranger conversion – looking for shifter information electricity magnetism and electromagnetic theory pdf

Hi guys. Haven’t posted in a while, but finally found a good Silver 92 to re-power our Scenicruiser. I picked up a complete ’77 Five Star General truck with the 8V92 (less than 8k miles since in frame rebuild) and a nice 13 speed Roadranger transmission. I currently have the original 4 speed spicer in the bus, and had bought an HT750 DRD a couple of years ago but never installed it (planning to convert to auto when I did the re-power), and now I am trying to decide if I should continue with the plan to go auto, or maybe put the 13 speed in. One of the big issues with the 13 speed is the shift linkage, and I checked a few of the old threads on BNO and found some comments on members that were doing conversions a few years ago, and suggested cable shifters, but could not find any details. I believe Bob Gilgert was using a 10 speed in his Eagle, Bob, if your still posting would be interested in how you set your shift linkage up. Or if anyone else has solved the linkage problem, I would appreciate your input. Lastly, if anyone is currently running a 13 speed in your bus, what are the pro’s and con’s. We do tow a large (16,000 lbs) trailer, so the DRD Allison, or extra gears in the 13 speed may prove to be valuable.

I had a cable shifter on my Kenworth cabover-1984 or newer had them, or K100E. Peterbilt, I believe also used them. Freightliner Argosy also used cable shifters. The advantage to the cable shifter is you can set it up so the transmission shifts with a normal shift pattern. I don’t know how you’d use the old shift linkages since the original four speed used one shift rod for 1-2 and the other shift rod for 3-4. Whereas the Roadranger need an X & Y shifter-meaning one for fore and aft movement and the other for side to side. You’d have a hard time setting that up on a Scenicruiser.

You’ll get the best fuel mileage with the 13spd. You’ll get the best performance with the Allison transmission. I drove for 21 years cross country to the tune of 1.3 million miles, always with a 13spd. My nod goes to the Allison transmission. I spent big bucks to change my truck from the 13spd single overdrive to the HT740 Allison, and have never looked back. By using the Allison, you’ll be able to have anyone drive the bus, as compared to the 13spd. Good Luck, TomC

Thanks for all the comments guys. The HT750 I have came out of Pat McNeil’s Scenicruiser when he had the 8V92 in it (before he re-powered with the Series 60). It was rebuilt but lost drive after a few hundred mikes and Pat never had it checked to figure out what was wrong with it. I pulled it out today, dropped the oil pan, and took a quick look through the access plates etc. Internally it looks new, so I am going to run it to the local Allison dealer and have them put it on the dyno to see if they can figure out what is wrong with it. I have a Stone Bennett Shifter and only need the adapter between the trans and the 8V92 to be able to install it. Definitely the simpler option if the trans checks out ok, or hopefully is only a simple fix. The more I consider the 2 options I am leaning towards the auto. I also spent some time under the old general truck and the 13 speed would definitely take a lot more to install. I also had a guy at the storage lot where I have the truck parked ask me if I wanted to sell the trans, so that may make the decision even easier 🙂