Spicer 4-speed shifting

[Dreadnought]

In this video I started talking about my challenges shifting my accursed Spicer 8245a at around 8:40

https://youtu.be/RWdZs_p7AN4?t=8m40s

It's lasted since 2012. In order to preserve my clutch life as much as possible in my last 5000 miles trip across the USA I've also learned to shift with no clutch. That has included shifting down. Several times I've managed to shift with zero to minimal grinding too.

Was annoying- then I added up my average fuel consumption bills and saw I was getting 8-10 mpg! I'm happy!

[bevans6]

Do you have an issue with your clutch, Dreadnaught?

[Dreadnought]

Do you have an issue with your clutch, Dreadnaught?

Yeah- the tap thing that you lift to adjust- at he back -I've followed procedure and its reached the limit of adjustment.

Sometimes even when stationary with clutch depressed, it doesn't want to go into first. It doesn't slip yet but I fear a new clutch will be needed soon.

[bevans6]

Dread, check your PM's, please.

[Dreadnought]

Dread, check your PM's, please.

Just did. Sorry, was in an interesting meeting

[HB of CJ]

The Kern High School District in beautiful Bakersfield CA way back in about 1969 taught us KIDS how to shift the old various Fuller and Spicer transmissions.  Took a little time.  Took some steel off the dog clutches.  But ... quickly we became quite good at it.

All the good rolling stock were Crowns.

Usually 743 220hp Cummings, (sp?) engines.  About 8 mpg.  Some had clutch brakes.   Not for shifting while rolling.  Abusive.  But ... handy while slowly going up steep hills when up shifting. Sometimes you had to.  The mechanics knew and understood.

Cummins.  C..U..M..M..I..N..S.  Cummins.  Cummins.  How dare me mis spell his name!  Sorry. 

The newer Crown Supercoaches at that time came with the famous, (infamous?) close ratio RTO910 10 speed Roadranger transmissions.  Extremely easy to shift.  The older 5 speed granny gear Spicers on the old 1955 or so Crowns were more of a challenge.

The older stuff had 220hp gasoline Hall Scot engines.  A whopping 3 mpg.

All it takes is practice.  Perhaps some adequate instruction from Old Coots who still remember such transmissions before the dawn of time?  You can learn how.  Just takes some time.  Also the mechanical stuff inside your Bus Conversion must be in good shape.

My final driver was a 1963 Crown 10 wheeler.  Old #21.  220-290 Cummings. (sp?)  RTO910.  Jake.  Ran the Ridge Route twice daily.

Any old trucker friends you can ask?  Young folks today can not even shift a normal manual.  Never learned how.  Any truck driving schools in your area?  Good fresh instruction today is always a good idea.  I would like to attend such.  A refresher.

Cold engine, warm engine, hot engine.  Cold tranny, warm tranny, hot tranny.  Up hill, down hill, level.  Road speed.  All makes a difference shifting.  Eventually it will become a muscle memory.  Instinctive.  Once learned it remains learned.  Much fun also.

[richard5933]

...Also the mechanical stuff inside your Bus Conversion must be in good shape...

At least that's one thing I've got going for me. The bus only has about 40K miles (original & actual miles, not just since a rebuild). Luke has recently had the bus in his shop and says it's as bone stock as they come and that the drive train is in top shape. At least till I started shifting it :{

[Bus Lurker]

I am absolutely jealous Luvrbus got to drive a 5 speed Brown Lipe with a 4 speed auxiliary transmission.  Most of these transmissions were gone when I started driving in the late seventies.  I've heard stories about when drivers shifted both sticks at the same time, they would need to shift with no hands on the steering wheel.

Chessie4905 is correct: the clutch brake, which should be felt when the clutch is fully depressed, will stop the gears from spinning so the transmission can easily be put into 1st or reverse.  The clutch pedal should never be fully depressed when the vehicle is rolling; that will quickly wear out the lining material on the clutch brake.  I have seen drivers ruin clutch brakes very quickly only to hear them later need to grind the transmission every time they slammed the stick into first or reverse.  Ouch!

When upshifting or downshifting, you only need to depress the clutch very little past the "free play" point in the clutch travel to shift.  An old crown school bus driver once told me that when he had a bus full of noisy kids, he was forced to drive by the tach and watch the RPMs to shift because he could not hear the engine.  We had a old time shop foreman who drew red lines on the face of the tach showing when to upshift and when to downshift.  Maybe someone here can tell what those RPM levels should be. 

You just need more practice to get your timing down to coordinate the RPMs, shifting, clutching and clutch braking.  Eventually it will all come together like a symphony!

There is a big benefit to having a coach with a difficult to shift transmission: it is a "millennial antitheft device!"

Mike       

[richard5933]

I've read in many places that the wet clutch in the 4108 does not have a clutch brake. It was explained to me that this is one of the reasons it is so difficult to shift into first gear. I just looked through the manual and parts book and can't find any reference to a clutch brake. Can anyone confirm the existence or absence of a clutch brake on a 4108?

[Utahclaimjumper]

  HB,, Clessie CUMMINS would not appreciate mangling his name,,this same mechanic/inventor invented the JAKE BRAKE..
.>>>Dan

[luvrbus]

I've read in many places that the wet clutch in the 4108 does not have a clutch brake. It was explained to me that this is one of the reasons it is so difficult to shift into first gear. I just looked through the manual and parts book and can't find any reference to a clutch brake. Can anyone confirm the existence or absence of a clutch brake on a 4108?

Could have been a option on the 4108,I have seen those on 4905 with wet clutches .When I change one over to V730 it had a brake

[RJ]

With the air throttle there is no feedback through the pedal.

Richard -

Wasn't aware that you also had an air throttle.  In that case, combined with the wet clutch, you've got the most "entertaining" combination GM ever built.

Also the most frustrating.

Here's a video of Fred Rayman shifting a Scenicruiser.  Dry clutch and mechanical throttle, thus different, but the shifting concept is similar.

https://www.youtube.com/watch?v=QlH3OrXcOdM

FWIW & HTH. . .

[Lin]

As was mentioned earlier, installing a tach can be a big help.  Although we have an automatic now, we did have a Spicer before, which a never particularly liked.  However, when our clutch began to fail, I had to learn to shift without it.  Using the tach to coordinate the gears made it easy.  We drove from near Palm Springs to Bakersfield only using the clutch to get into first from neutral.  It actually made driving much more pleasant.

[richard5933]

Richard -

...In that case, combined with the wet clutch, you've got the most "entertaining" combination GM ever built...

That's what I was going for...entertaining.

I've watched that video of Fred dozens of times. Makes it look so very easy, almost like he's been doing it for decades.

I'll be picking it up tomorrow from the shop after they did a few more minor tweaks for me. They're keeping it inside tonight, so at least I won't be driving it on an ice-cold transmission. I'll try the techniques in your article RJ and see how it goes.

Biggest thing that I really have to work on is not stressing about traffic behind me. Panicking does not help make the shifting smoother.

[chessie4905]

Ok, went out to shop and checked manuals. X8064 operator's booklet doesn't have any mention of the brake unit. X7564 maintenance manual doesn't talk about it, however transmission breakdown illustrations show it. Listed as #44- countershaft brake cover, #46- reaction plate, #47-disc assembly, #51- reaction plate, #55 countershaft brake retainer, ND some other small items. There is no separate section for 4108's trans. On rear of transmission near output shaft where driveshaft is connected, there is about a 5 inch slightly rounded square cover with 4 bolts. You can remove this to check condition of discs. I don't recall losing much oil when pulling cover. discs are easily removed. If they are shot, it will be obvious. I did read somewhere that you only pushed clutch pedal clear to floor to engage 1st gear. Nor more than half way to upshift or down shift. Operators manual directs driver to accelerate to engine to full governored speed before upshifting or downshifting. Shifting speed will be faster when trans is cold