Teach me how to drive this Manual - Page 2
 

Teach me how to drive this Manual

Started by Bryan, March 18, 2014, 03:11:45 PM

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rgrauto

Rj. Thanks for the heads-up on the Gm. clutch adj. I owned a 4104 before the MCI but that has been a while ago.  Bryan if you need some help message or give me a call ,Y'all have a good day.

FolkBus

Hi Bryan, everyone above has given you great advice. In my off and on career as a bus/truck driver. I have driven GMs, Eagles, MCIs and Prevosts. The only constant is that they all have a different feel. You will find your coach's personality and then enjoy. Just remember  how big you are and how long it takes you to stop ( I call it situational awareness ).  Shifting will come in time but is not the most critical. Take you time and have fun.

--Mike


Sent from my iPad using Tapatalk
Mike and Debbie McNeil  Ridgway - Montrose, CO
1949 Crown SuperCoach (Amazing Grace) Conversion 1972  Pancake 220 Cummins  Fuller 5 Speed

1967 MC-5A  (Serenity)  Conversion 1986  8v-71N   Allison MT-644

TomC

With only 4 speeds, the buses were designed to rev to governor then shift. Since no tachometer, you shifted by speedometer. Make note of shift points, possibly putting a small arrow at each shift point on the speedometer. Rev to the governor and then shift-double clutching-think of it as first shifting into neutral then shifting into the next gear depressing the clutch each time. Part of the reason Detroit 2 strokes worked so well is that they fell down to idle very fast compared to a 4 stroke engine-hence could shift very fast.
The best way to master a manual is to switch to an Allison automatic. And this from myself that was a cross country truck driver for 21 years and 1.3 million miles on 13spd transmissions. Once you experience the performance and ease of driving an Allison, you'll never go back to a manual. Good Luck, TomC
Tom & Donna Christman. 1985 Kenworth 40ft Super C with garage. '77 AMGeneral 10240B; 8V-71TATAIC V730.

lostagain

All good advice above, except I don't recommend shifting without the clutch. When you miss a shift, you will break expensive parts in the transmission. The bus was  engineered with a clutch, use it.
JC
Blackie AB
1977 MC5C, 6V92/HT740 (sold)
2007 Country Coach Magna, Cummins ISX (sold)

wg4t50

Always felt once you got the feel of the setup,  using a clutch for anything but starting or stopping was immoral  ;D
Dave M
MCI7 20+ Yrs
Foretravel w/ISM500
WG4T CW for ever.
Central Virginia

bevans6

I posted these photos recently, but this time to illustrate the tiny dogs that engage the splines in the shift hubs in the Spicer 8844.  This one is an in-line but the boxes are about the same internally.  You can see the tiny dogs, about 1/4" wide and tall, at the base of the gears.  They are identical to the splines on the main shaft that the shift hubs slide along.  There is almost no play between the internal spline and the dogs on the gears where they engage.  You can also see the rounded, almost pointed, face where the hub slides over the dogs to engage it.  That is what is rattling or grinding when you miss a shift.  Gearboxes that are designed to shift without a clutch have very large dogs and far fewer of them, and there is a lot of space between them so when you unload the box it slips out of gear and then the large dogs can almost fall into place on the next gear.  This Spicer ain't like that.  Sure you can shift it without a clutch, but these photos show exactly why that is a dumb idea.  It just isn't designed for it.  It was designed to be strong and cheap.  Those tiny little dogs can transfer immense torque and last a very long time - if a poor operator doesn't chip off a dog and ruin the gear.

Edit: the bottom picture is a closeup of the splines on the main shaft and the dogs on the gear.  You can clearly see the sharp, square profile of the splines that the shift hub (in this case the shift hub is also reverse gear) slides along, and over the dogs with the very worn, rounded noses that are on second gear.  They are each about 1/4" wide and are a very good fit, there is almost no slop at all between the shift hub and the gear once it is engaged.

1980 MCI MC-5C, 8V-71T from a M-110 self propelled howitzer
Allison MT-647
Tatamagouche, Nova Scotia

shelled

Two things to add -- the advice from RJ and others is spot on, however there are a couple of things That help putting it into practice.

First, the gearbox and drivetrain do 'talk' to you through your fingers as long as you do not grab the shift lever in a death grip.  You might think of it as being like tickling fish (without the wet and slimy part) if that helps.

Second, every part of the drivetrain is subject to it's own inertia.  Matching the relative motion (RJ's count during shifts) can't be sped up without making embarassing and potentially expensive noises.  This makes it especially important to 'drive ahead' anticipating road and traffic changes before they become necessary.  Don't be an emergency looking for a place to happen.

e3
Rampside/UltraVan/Excalibur/4104/4107/etc -- Dallas Tx

gus

I drove truck before I got this bus and own two heavies now. You can forget 90% of truck shifting experience with this 4-sp, hardest thing to shift I ever drove!! I attribute this to the long linkage, just my guess.

Many trucks have clutch brakes, this does not, whole new ball game!

Shifting without a clutch is no more harmful than with, a missed shift is a missed shift either way. There is no difference in gear raking either.

I've been doing it for years with no problems. Actually it saves wear and tear on the linkage!!
PD4107-152
PD4104-1274
Ash Flat, AR

digesterman

Quote from: TomC on March 19, 2014, 08:20:48 AM
The best way to master a manual is to switch to an Allison automatic. And this from myself that was a cross country truck driver for 21 years and 1.3 million miles on 13spd transmissions. Once you experience the performance and ease of driving an Allison, you'll never go back to a manual. Good Luck, TomC

LOL, could not agree more. I like to enjoy the trip, not get there dripping sweat.
Lee
Le Mirage XL 45E
Detroit Series 60
470HP
111,230 original miles (11-2015)

digesterman

Quote from: lostagain on March 19, 2014, 11:44:31 AM
All good advice above, except I don't recommend shifting without the clutch. When you miss a shift, you will break expensive parts in the transmission. The bus was  engineered with a clutch, use it.

Most good tranny shops can tell when rebuilding a tranny if the driver was shifting without a clutch or not. Most companies frown on this practice because they know what maintenance costs.
Lee
Le Mirage XL 45E
Detroit Series 60
470HP
111,230 original miles (11-2015)

wg4t50

Some times you just have to laugh, a good friend who can do anything, welds look computer done, really can do anything EXCEPT shift gears, some where between the clutch, throttle and gear shift, everything goes out the window ;D  A great guy, just this hangup with a gear shift.  Everyone still laughs about it.  You have to see the humor in this.
Dave M
MCI7 20+ Yrs
Foretravel w/ISM500
WG4T CW for ever.
Central Virginia

wdtjawshwdt

No clear answers on "slip shifting" or "double clutching"  in trucker forums.  Do what works Bryan.   Haha.   The biggest thing is syncing your transmission with the engine. 

I have only gotten to run my MCI on one long run and I have to agree that the temp of the transmission does make a difference.   From what I remember I did end up double clutching when I took all my buddies on a bar tour because it just wasn't slipping as easy.   

I have just become a lazy truck driver and don't like my left leg getting too tired.   
Josh
1981 MC9 6v92DD 5 speed fuller
RIP 1996 Amtran dt444e

Farmington MN

georgemci102a2

..+ 1.. ;D...George...ps look for the left leg limp ;)
1988 mci 102a2/6v92ta/Grovetown,Ga.

RJ

Quote from: Runcutter on March 19, 2014, 06:13:13 AM
The first year we had air-throttle buses, 4905's 252 & 254, I never could shift the darned things.  Engine revs would die down too quickly.  Other drivers could handle them, but I hated those buses.  I'd never take one out to instruct, since I couldn't shift the darned things to my satisfaction.  

Arthur -

Wet clutch air throttles were fun, weren't they!   ;D

Quote from: TomC on March 19, 2014, 08:20:48 AM
The best way to master a manual is to switch to an Allison automatic.

Good one, Tom!   :D


Bryan -

The best way to learn is to practice.  Then practice some more.  It will take awhile to learn your coach's "feel," but once you get it, you'll be good to go forever - like riding a bicycle.

FWIW & HTH. . .

;)
1992 Prevost XL Vantaré Conversion M1001907 8V92T/HT-755 (DDEC/ATEC)
2003 VW Jetta TDI Sportwagon "Towed"
Cheney WA (when home)

TomC

Here's a comparison picture of the sliding synchronizer on a 10spd Roadranger transmission. You can see by the thickness and gapes between that these transmissions are made to be shifted without clutch. Good Luck, TomC
Tom & Donna Christman. 1985 Kenworth 40ft Super C with garage. '77 AMGeneral 10240B; 8V-71TATAIC V730.