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Author Topic: 13 speed  (Read 1594 times)
harpold700 3
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« Reply #15 on: November 23, 2017, 04:14:38 PM »

Heck with all this transmission swap, I'll just turbo it, thanks for all the input.
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buswarrior
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« Reply #16 on: November 23, 2017, 05:28:33 PM »

Now your talking... !

Turbo motors also make lots of heat...

No free lunch?

The cooler for an auto isn't a big deal, mount in the side door, and put a proper fan, job is done.

I like a 13 speed too...

Happy coaching!
Buswarrior
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TomC
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« Reply #17 on: November 23, 2017, 06:07:39 PM »

If you have a 4spd manual, your shifter works with two rods-one rod for 1st and 2nd, the second rod for 3rd and 4th. Both rods only move fore and aft-no side movement. That's why reverse is taken care of by electric solenoid shifting to 2nd.
Any other transmission you want to put in you need an X and Y shifter-meaning one rod or cable that goes fore and aft and the other goes side to side. Gillig and Crown and many other rear engine buses with multiple spd transmissions typically used a single long shifting rod that goes fore and aft and rotates for side to side-built much like a driveshaft with U-joints in them for going up and down with the floor. Or for conversion can use a shifter from a cabover that uses two Morse type cables for the fore and aft, and side to side.
Still complicated to switch-better to just drop in an Allison automatic. Good Luck, TomC
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Tom & Donna Christman. '77 AMGeneral 10240B; 8V-71TATAIC V730.
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« Reply #18 on: November 24, 2017, 06:24:16 AM »

It hasn't been covered but a good thing about a Allison is the torque converter will let the engine build up the torque faster and easier
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Geoff
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« Reply #19 on: November 24, 2017, 07:02:12 AM »

I agree on the Allison.  Shifting a Roadranger and having to use a clutch in stop and go traffic gets old.  For transmission cooling, the stand alone cooler from a V730 works well and are easy to find.
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Geoff
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« Reply #20 on: November 24, 2017, 07:58:55 AM »

I had a 10 speed RTU in the Prevost.  It was OK but no way would I swap transmissions and install a Roadranger.  If you're going to the bother and expense of a swap, do it right and get you an Allison.  The RR was great on the road but so's an Allison in lockup.  I had a few extra gears so - in theory - I could pick the right one for the situation easier than with an auto but that was the only advantage and its mostly a theoretical advantage.  The real problem with a RR is in town in stop and go.  You're always going back and forth from Hi to Lo range and the 13 isn't going to be any different than the 10 speed.  Somewhere around 20 MPH you're going to have to change ranges and go back across the shift pattern and then the brake lights ahead of you will come on and there you'll be, going back down into the basement and then traffic will start to move again and you're back up across the gate.  It gets old real quick.
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R.J.(Bob) Evans
Used to be 1981 Prevost 8-92, 10 spd
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« Reply #21 on: November 24, 2017, 08:31:44 AM »

When I was driving truck and was in town with my 13spd, I would always skip gears. I'd start in 2nd, shift to 4th, pull up the button then shift through the gears of 6th, 8th, 10th etc. Drive it more like a 6spd, then when on the highway kick it into overdrive with the air switch on the shift knob.
Driving a 10spd would be the same thing. Start in 2nd, shift to 4th, pull up the button, then continue with 6th, 7th, etc. There's nothing written that you have to go through all the gears all the time. Good Luck, TomC
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Tom & Donna Christman. '77 AMGeneral 10240B; 8V-71TATAIC V730.
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« Reply #22 on: November 24, 2017, 11:32:41 AM »

My old 1974 long gone, (I am now bus less! Sad) Crown Supercoach would easily pull down or high idle lug down to about 12 mph in 6th gear on flat ground.  Still in the high side.

Then quickly accelerated with just a little bit of right foot.  The cruising sweet spot seemed to be right at 1500 rpm which equaled 60 mph in 10th gear.  Fuller RTO910.

Like already said better, one did not have to use all the gears.  Normal starts were made in 2nd gear.  Tenth, (10th) gear was only good for about 60 mph or faster.

Sometimes that desired 60 mph could only be maintained in 9th gear.  Certainly not a hot rod.  Small Cam C U M M I N G S 250.  No turbo.  The gears were very close.

This made maintaining a certain road or traffic speed very easy, within the power capabilities of the Crown.  A gear for every situation and some gears you did not need.

The RTO910 was certainly a better more flexible tranny than the usual Fuller T905 5 speed.  Where it shined was tight twisty mountain road driving maintaining speed.

Where it DID NOT shine was in that aforementioned horrible stop and go driving below that critical low speed of about 12-15 mph.  Then you wandered between lo and hi.

But ... on the open road it was superior.  My opinion only.  At speed one did not have to shift at all.  But ... if the engine began to work and the road speed began to drop?

Very easy to drop one gear.  Then another gear.  Easy to keep the rpm up.  But ... nowadays BETTER transmissions exist?  Oh yeah.  How about a New World 6 speed?

Kinda like the neat HT740 but with two additional over drive gears?  Or ... 66 mph, 85 mph, then 100+ mph?  Plus no clutch pedal.  No double clutching.  No tired left leg.
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bobofthenorth
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« Reply #23 on: November 24, 2017, 11:44:07 AM »

Everybody skip shifts a RR once they get used to it.  Unless you guys are claiming you could start in 6th you still have to go back and forth across the gate in town.  Your knee still gets sore over time.
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R.J.(Bob) Evans
Used to be 1981 Prevost 8-92, 10 spd
Currently busless (and not looking)
My website
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Simply growing older is not the same as living.
harpold700 3
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« Reply #24 on: November 24, 2017, 02:59:19 PM »

I have been driving for31 years, shifting is not scary . 13 speed would be killer behind 318, but at what labour to do it.  This stand alone V730 cooler you speak of interests me, I have access to an Ht747.  Am I heading down the right road ? Any advice or directions to said V730 coolers? thanks.
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« Reply #25 on: November 25, 2017, 08:42:21 AM »

Just look at Hayden web site. You need 1" fittings. They many coolers with and without built in fans for Allison transmissions. I have both the standard shell cooler that uses the coolant from the engine. I added an air to oil cooler with thermostatically controlled fan to take the initial heat load off. So the transmission fluid flows first through the air to oil cooler then flows through the coolant to oil shell cooler. I did this hoping to keep some transmission heat from the radiator.
The secondary advantage of the coolant to oil shell cooler is that it heats up the transmission faster and actually will keep the transmission from running to cold on a wintery day. Good Luck, TomC
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Tom & Donna Christman. '77 AMGeneral 10240B; 8V-71TATAIC V730.
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« Reply #26 on: November 25, 2017, 09:04:33 AM »

I've never seen an automatic transmission not work right because of cold weather unless it has a problem. All the automatic trans I see now use a separate air cooled  unit.
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GMC h8h 649#028 (4905)
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« Reply #27 on: November 25, 2017, 09:19:21 AM »

Most all the buses with the 4000 or B500 use a water to oil cooler the B500 needs to reject 340,000 btu of heat per hr minimum the old 700 series required 4000 btu per minute     
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« Reply #28 on: November 25, 2017, 10:20:47 AM »

I have used a laser temperature gun on my V730  transmission and it runs 180f, same as the engine.
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Geoff
'82 RTS AZ
harpold700 3
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« Reply #29 on: November 25, 2017, 06:31:38 PM »

Thanks, I'm on it.
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