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Discussion Starter #1
I have been trying to examine as many possible gearing solutions as I can to determine what setup will work best with a Cummins 4BT, that will give me a tolerable Hi-way RPM, and a decent crawl. Considered a doubler, and while that works off road, and allows me to run relatively tall gears and still have a good crawl, it isn't as versatile on road.

I already have a TH400 from behind a Cummins, but I was really wanting a 4-speed. Well, I just landed a complete Ford setup, with adapter, flywheel, and NP435, and Have been crunching some numbers. Tripped over the Ranger OD listed in Hi-Impact's Site http://www.high-impact.net/transmission_and_gear/rangeroverdrive.htm, and pulled out the calculator, and really like what I see.

What I'm considering is putting an air-shift cylinder on the Ranger, with a shift toggle from an 18 wheeler on the shifter, so that I can split shift it, in effect giving me an 8-speed. A little complicated, but won't really have to use the split's much, and it's a hell of a lot easier than an Eaton 18-speed. These are the gear splits I'll end up with, and they seem pretty uniform, but I'll need to spreadsheet them to see how the RPM matches up at each shift point.

6.68 4.87 3.34 2.43 1.74 1.27 1.00 0.73

Thinking an NP205 t-case, with 5:13's in the axles.

That will give me a Crawl Ratio of about 68:1 which I can live with, and a Hi-way engine speed of about 2000RPM at 65MPH, which is about as fast as I plan on driving this thing, and is right in the Cummins sweet spot.


What am I missing here. This seems like it's a perfect setup, and versatile as hell. It actually seems a bit too perfect. Anyone have any experience with these? As it stands now, this is my final driveline design unless I hear some negatives.

Thanks
Doug
 

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i pretty well arrived at the same conclusion. i had looked at vacuum shifting, but air would be easy if you have a compressor. only thing that held me up was i would be waiting a long time for parts if it ever died. that said, i haven't used one. people do reckon they are pretty reliable.
 

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One thing to consider is the Ranger is not synchronized (I don't think).

About the air shift part, while it sounds like it will work, it may not shift as cleanly as you like. I am sure with practice it can be mastered, but it may not be for everyone.

Another thing, on a Roadranger the gear shift switch, actually an air valve, can be changed while the 5 speed part is still in gear, but the two speed part won't complete the shift until the main stick is shifted into neutral.
I could see a problem if you bumped the range valve while driving, unless you figured out how to interlock it with the 4 speed.

Also, a Roadranger, while not fully synchronized, the two speed part is, so when you shift the air valve the range shifts for you, no speeds to match, the high low shift will be in gear by the time you get the stick into the next one.

I have a Roadranger RTO-6610 (ten speed overdrive) in my truck, it's the "smallest" Roadranger at 357lb. While it did take a week or so to get the hang of shifting without grinding gears or clutching, I really like it, and the 500 rpm drop between shifts.
But it may not work for you, as there are no transfer cases that bolt on, divorced is the only option for four wheel drive, and a reasonably long wheel base will be needed to fit it.

If you go with the Ranger box, keep it manually shifted. An air cylinder is not forgiving, and because it is not synchronized I am sure you will grind the gears plenty until you get the hang of it, if you do...

Grigg
 

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Discussion Starter #4
Actually, the Ranger is synchronized. That is one of the attractive points to the whole thing. The other issue is whether or not it can be switched while in gear. I see no reason why it couldn't, since it will shift very much like a semi in that respect. As long as it's under load, then as long as you aren't using too powerful a cylinder, and it'd have to be a damn big one, it will not shift.

I drive Semi's more than a little, With quite a number of different transmissions, and the fact is, you have to adjust your shifting to each of them. Don't really see this as being much different.

Will it work? Hell I don't know. You bring some good points up, but at the worst, even with air, you have to time your shifts and massage it in. It seems as you know that already. Worst case scenario, is that it's not feasible to split the shifts, but you end up with a manual shift overdrive. Sounds like a cheap alternative to swapping in a NV, that can be adapted to a number of existing drivetrains.
 

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That's good news then, that the Ranger is synchronized.

I suspect it will work as you say.

Pick an air cylinder that looks about right, and you should be able to fine tune the shift with an air regulator. The Roadrangers use about 70 psi, and the cylinder is about 3" diameter. It directly slides the gear/ synchronizer, no linkage or added leverage. Now, an old R-96 Roadranger has an external air cylinder with linkage for the range shift.

All I would be concerned about now is not having an interlock. Perhaps a neutral safety switch and a solenoid valve could be used so the range would not shift unless the main trans is in neutral?

Grigg
 

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Ranger OD info

I am planning to use the Ranger OD in my setup too. Advance Adapters manufactures the ranger od. You can get a parts list and instruction sheet from them (phone 800 350 2223).

Lewis

81 J10
4BT
Muncie 465
208 xfr
3.31 diffs
 

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Borg Warner T-19 Ratios

Your ratios are incorrect if you have the fully synchronized T-19 that came in the step vans. They are:
4.02 First
2.41 Second
1.41 Third
1.00 Fourth
The T-19 that was used came with two PTO covers which the T-18's did not have.
 

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Discussion Starter #8
Your ratios are incorrect if you have the fully synchronized T-19 that came in the step vans. They are:
4.02 First
2.41 Second
1.41 Third
1.00 Fourth
The T-19 that was used came with two PTO covers which the T-18's did not have.
NP435
 

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I am considering putting one between the 4BT and sm465 in my (now) 14000lb orange bread truck.
seems like it would give me most of what I want in terms of gears.
though, Idealy I would have one lower and another overdrive.
I wonder how fast one can be shifted?
as I will have to get good at shifting 2 stiks quickly on uphill shifts.
the sm465 does not shift quikly, at this point, so I figure I should be able to stab the clutch , and shift the ranger by the time sm465 has wound down and is ready?????
Im sure there is a fancier way but if it will work, these kind of challenges keep me on my toe s driveing.
another question is will I destroy it. Or how fast?
says its rated for 25000lbs, 420 ft /lbs torcch.
the torque part dosnt mean to much to me but doesnt seem like that much when I think of torquing my lugs at 150.
I realy drive that bread truck on some steep s.

the other option I'm considering is an old 3 or 4 spd aux. tramsmission.
are these things siyncronized ? do they shift well?
if it was the right one , and it worked, it would probly give me all I want.
it could cost less...or more.
it would certainly be much more modification.
I certainly have space, and plenty of driveline.
its alot more driveline modification.
I dont have a clue how I wuold deal with the shift linkage
mounting doesnt seem to hard
finding the right one would probly be the worst part
I dont realy need to add any more weight to my truck , either

thoughts?
 

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I have a Rager and an sm420 in my 6bt powered scout and love the set up. I have 2.72 gears in the axles. I start in 2nd, go to 3rd, then 4th, then overdrive normaly. I have plenty of power and don't need to split gears but can if I want. Sometimes it is nice to split a gear in the hills with curves so I can find a gear that I can just leave it in and not shift.

I bought a P30 bread van last week with a 4BT. It has a T19. I'm going to put a Ranger and SM420 in it too. It will really help when it is loaded with the lower power of the 4Bt.

If you put the levers close you can one hand spit shift. I often go from third over to 4th direct with one hand on the main knob and the bottom of my fore-arm on the ranger stick. If your good you can do it without the clutch.

One slight negative is that the main box shifts a little harder due to the extra rotational mass on the imput shaft....
 

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thanks
that is encouraging and helpful.
how much harder to shift?
the main box already shifts a bit hard but maybe I will plan to adresse that when I pull it out.
I heard the ranger is pretty loud. well so is a 4bt, is it noticible? is it bad?
 

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Id also like to know more about the noise
im going to use a Ranger in front of my Toyota 5 speed in my Landcruiser and keep the 4.11's
according to my math (which isnt my strong point) id be about 1600rpm at 100k
how many miles on your set up
 

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The noise is a gear whine in over drive, i can hear with the windows up in my truck.

I have 50000 miles on a used ranger in a 6000 pound 4x4 with a 4bt and no change from when i put it in.
 

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I have about 3000 miles on a new Ranger III OD in my vehicle. When I first installed the OD there was some gear whine. I put Redline 75-90 NS gear oil in the OD and the noise has stopped. So if you have gear noise you may want to try a different gear oil.
Shifting my trans (SM 465) was harder when I first installed the OD (I rebuilt the trans about 8000 miles before I installed the OD.) After I put approximately 1000 miles on the OD the shifting got easier.
I usually split my gears while up shifting and downshifting to keep my RPM below 2300 RPM. Up shifting is no problem. When downshifting I shift the trans with the OD in overdrive. Then shift the OD back to low range. This allows me to shift at about the same points as before the OD was installed also, at times I double clutch which improves my shifting.


Hope this helps.

Lewis
 
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