I dont want to start a new Discussion about Automatic or manual Transmission in a Bus. Looking for Members that have a Roadranger Transmission and can give me some info. How they arranged shift linkage and clutch assist. Problems or Tips !!
I will be changing from a HT748 to manual, so i have to start from zero and fabricate clutch linkage and pedal and complete shift linkage!!
I can't help you with that but the roadranger is the best tranny ever put in large vehicles.
Wow, what a project! Lots of folks go the other way, but only a very few go your direction and usually it is done as a part of an engine swap.
If your model Neoplan offered a standard transmission, find a parts bus and get everything you need to change over.
If you can find a standard setup for the Neoplan it will be for a 4-6 speed transmission. I assume you are looking at something like a 10 speed. Folks have converted from a 4 speed to a 10 speed often. As I recall they use a cabover tower.
You might think about an Eaton (roadranger) AutoShift/AutoSelect. They are the same transmission and computer. However, if the AutoShift does not see a J1939 signal from an engine ECM (as would be the case with a mechanical engine) it reverts to an AutoSelect, where the driver makes the shift by moving the button in the direction he wants to shift (up or down) and then synchs the engine speed with the transmission speed with the throttle (via a gauge that shows you which way the engine needs to go. You would need to make an electronic cable (not a huge deal), but you would not need to deal with shift linkage.
For the clutch use a hydraulic system. Volvo truck does that and you can pirate the parts from a truck.
Lots more to talk about, but I have to run to a meeting. This post might trigger others to respond.
Jim
thanks for the replys!!
and yes, im getting ready for a repower to cummins l10. its a long story, but first i was going to go with a B400 transmission. that way i could keep the stock 4.63 gear ratio. if i find to many problems in the roadranger idea , i maybe go that route.
im also not a fan of the autoshift transmissions , and because i will go with a mechanical engine its not really an option for me.
i have the offer for a 13 speed with double overdrive and all the parts i need from that truck. should give me all the right gears for the l10 with my rear end.
if i go with a 10 speed or even a rto 910 i also would have to swap my rear end .
still havent found a pumpkin that would interchange with my bus!!
thinking about a single shift rod, with a cabover shift cover. but have to figure out how to reverse shift points!!
yes lots of issues still.
I replaced the 4 speed with a 10 speed roadranger with 10th direct, nineteen years ago in My 01 Eagle, the problem is that the shift pattern was backwards. sooo on a open road the first hill I would come to I almost always wanted to shift the wrong way. the way I remedied the problem was to cut the cabover adapter rotate it 90 degree's so that the shift rod came out on the other side of the transmission now the pattern is correct. and forty years of habit is not tested every time I shift the old girl.
Busron
Since your bus is a transit, quite possibly a manual transmission setup was never made. That means you'll have to create your own shift tower-as previously stated from a cabover. Both late Kenworths and Freightliners used a two cable system to shift the transmission. One for fore and aft, and the other for side to side shifting motion. Granted that would mean running control cables from the front to the rear, but then you would be able to hook up the shift cables to the transmission so the shift pattern is the same and not backwards. The two main advantages to the 10spd manual is a gear for every speed, and fuel economy. Disadvantages-always have to be shifting, slow acceleration from a stop, harder to shift with the long shift cables, very few people know how to drive a 10spd.
After 21 years of driving nothing but 13spds (I still think the 13spd is the best transmission) for 1.3 million miles, I simply adore my Allison V730 in my bus and my HT740 in my truck (that I replaced the 13 spd with). The advantages to an Allison-acceleration from a stop like a car, anyone can drive it, smooth shifts, impossible to miss a shift, easier on the drive train, higher resale value (most everyone wants an automatic in a motorhome). Disadvantages-creates extra heat, less fuel mileage then the 10spd. Good Luck, TomC
Reversing the shift pattern is easy if you are building something (or modifying) from scratch. If you think of the shift lever at the front, if you have the rod attachment above the pivot the shift pattern is one way, if you have the rod attachment below the pivot (the way my MCI shifter is set up) the shift pattern is backwards. Shift knob forwards, rod goes backwards. What's harder is to get a single rod to rotate for the side to side movement. In race car shifters we do that with helicopter linkage Apex joints.
When I think about putting a 10 speed sort of manual transmission in a bus, what I think of is having a greater selection of gear ratios to match to load and road conditions, and skip-shifting. I might only use 4 or 5 gears going from a stop to cruise speed, not shift through all 10. I might have what I would consider 3 top gears, for different grade conditions. Is that a reasonable way to approach a multi-gear manual transmission in a bus?
Brian
Yes that is a way to approach a multi speed transmission in a bus. BUT- we just plainly do not have the weight considerations that trucks do. Hence, the 4 spd manual was sufficient for many years of bus service. I agree that 4 spds is just not enough. Add two more lows and an overdrive and you have the Eaton/Spicer 7 spd. The 7 spd would be my choice for manual transmissions in a bus (the 13spd is my choice in a truck). With the 7spd you have a heavy duty twin coutershaft transmission (up to 1450lb/ft torque) with no air operated splitter or range control (the 9, 10spds have a range controller, the 11, 13, 15, 18 have the additional splitter controller), with sufficient low to eliminate clutch burning, and an overdrive for better fuel mileage. Even though the 7spd is a non synchro transmission, it is easy to drive. Good Luck, TomC
Tom, we had a bit of a conversation a while ago about the design of the shift dogs in the Spicer vs what you expected in a "truck" transmission, and how that affected the ability to shift without the clutch. Your comment was that the dogs on the Spicer looked a lot like the teeth on a synchromesh hub, but the dogs on a truck transmission where a lot coarser, hence easier to shift without damage. How does that relate to the Eaton/spicer 7speed? does anyone have an installation diagram with dimensions for the Eaton/spicer 7 speed?
Brian
The problem with a single overdrive is that it would give you the equivalent of a 3.38 rear end (4.63 * .73). That would be a good gear for a two-stroke, but would be a bit shy on a four-stroke. I can see why the OP is considering a double overdrive.
I have been thinking a lot about this swap. I have done some pretty serious modifications to my bus, but the difficulty of this swap is right up with what I have done. The issue is value vs effort. Only the owner can make that analysis.
Obviously, the engine will need to be pulled (not a huge deal if you have the equipment). A new drive shaft will have to be made, since the manual transmission will be shorter (at least for a 10 speed - not sure on the 13 speed). I suspect that the transmission is "hung" off the engine - thus engine mounts would not be an issue with the 6V92. Mounting the transmission to either the 6V92 or the L10 can be done with standard parts.
Running the clutch and transmission cables/rods and mounting a clutch pedal mechanism just does not seem to me to be a fun job.
One benefit, is that your cooling capacity will benefit.
Jim
Lengths of Eaton/Roadranger transmissions- 25.6" for the 6spd; 28.9 for the 7spd and 9spd up to 1650lb/ft torque; 29.5 for the 1850lb/ft torque 9spd; 29.9" for the 10spd; 33.1" for 9spd with Top 2 automatic, 8LL, 13 and 18spd. Good Luck, TomC
Looks like im getting some info here!!! thanks to all who are trying to help and chime in!!
i agree that a 7 speed would be enough gears in a bus. only reason why i would go with 13 is to get the double overdrive , so i dont have to change my rear axle also!!!!!
on the other hand , with prices for bus shells as low as they are right now, its not far fetched to think about looking for a new "old" bus with the right drivetrain. but due to my situation , that im not sure how long we will stay in the US, i guess i will keep my workhorse. i build it myself so i know all the flaws and troublespots. also it keeps me from blameing others and gives room for improvements. lol. its also fun to prove that a transit can do the job and be fun to drive.
i still look into all my option i have . if i better go with less gears and spent some time on a rear axle swap, or if i follow the double overdrive route.i am also still open if i keep the 6v92 for this year and just change to a 9 speed with overdrive. mpg doesnt concern me to much, as i drive on free wvo trouble free for years now. so my radius depends only on how much fuel i carry with me. on our 2000 mile roundtrips we mostly get away with less then 30 gallons of diesel. most of that used for the heaters and generator.
what i am missing next to 5-10 mph more cruise top speed , is some hill climbing speed while towing my loaded trailer. i just find myself to often downshifting at a grade and with the large steps on the allison ht 748 im loosing speed faster then i want.
i also go by what s easily available on the long run. i found that its harder to find decent running 6v92 or even a not worn out ht 748. while cummins l10 are piling up from running takeouts out of trasch trucks or transits that changed to cng or got phased out. at least thats how i got mine !!
im still open to all options and ideas. also i would like to see detail pics of areas like clutch linkage and shift towers and linkage. i like the idea with turned cabover shift tower. on cable shifters i dont like the idea that the feel will be pretty stiff. at least thats what i thought while testing a KW cabover.
so a single shift rod is my winner for now, till somebody shows me a better solution.
it will be tight , as i dont have much room on top of the drive axle. but i got my 1" coper pipes for the wvo heater through it , so i will find a way for the linkage.just more ideas for now!!
thanks to all and keep on coming with info.
Would anyone know if the O/D six speed spicer is the same dimensions as the O/D seven speed spicer and mounts the same? are the ratios just a bit closer throughout for the seven or is it just another reallly low?
Thanx
glen
NeoplanAN440- I hate to burst your bubble-but-as to overdrive ratios, the 7spd is .75. Granted the 13spd is a double overdrive, but with .86 & .73. As example-if your top speed now is 70mph @ 2100, the 7spd will bring your engine speed to 1575, and the 13spd to 1533-not that much difference. If you really want a significant drop, then use the Allison World transmission with its' .74 and .64 overdrives to drop the engine speed to 1344. Good Luck, TomC
We've got a 10 sp RR with a single rod shift linkage. I never could figure out what the shift tower was but after reading this thread I expect it is a cabover tower. It took me a while to get used to it, doubly so because it has what I believe is called a "U" shift pattern:
2 5
1 3 4
Typically I shift it 2,3,5,7,8,9 unless I'm pulling a heavy grade. I like the fact that I can usually find a hole that lets me wind the 8-92 out fully when I need to. I'd probably prefer an automatic but not enough to go to the effort of changing it. What I particularly don't like about a 10 speed is that you have to go back and forth between high and low range when you are driving in town. That gets old real quick.