Hello! New 4106 owner. Have shifting trouble (spicer 4-speed)

[RJ]

Andy -

I'd suggest you take it out this weekend to a nearby industrial park where 90% of the businesses are closed for the weekend to practice.  Lot less traffic in those areas.  Especially at 0800 on a Sunday morning!

The clutch can be heavy or really light, there's a whole bunch of factors involved.  First is proper adjustment, which actually, according to the book, starts up front and works it's way back.  At this point in time, it's not unusual to have a lot of slop in the linkage, slop that needs to be rebuilt to remove it and improve the clutch action.  Worst case scenario is the wrong clutch parts installed at some point.

Some folk may chime in and say put an Allison V-730 automatic in it, but if you enjoy the manual, it's a moot point.  Can be a PITA when trying to wiggle into some campsites perhaps, but that's why you scout out your parking site first.  It's also a PITA in heavy traffic (Dallas?  Los Angeles!), but if you avoid major commute times, that can be avoided somewhat.

OOOPS!!  Major mistake alert!

I just re-read my post to answer your question, and realized that what I said was bass ackwards to what I meant!

What I meant to say was that as you find the coach stabilizing and you can pull it out of 1st with the clutch out, bump the shift lever up against 2nd with the clutch OUT (not in!) and feel when it starts to drop into gear as the engine RPM falls off.  Immediately kick in the clutch so you can come to a stop and try it again w/o causing a lot of bucking of the drive train.  Be sure and LISTEN to the engine as you practice this, too.

Clear as mud?

FWIW & HTH. . .

[Scott & Heather]

Ok, this has nothing to do with your thread, cause we have an Allison auto trans, but you're young and so are we, and we are in Keene, TX and live in our MCI bus. So we must connect. I'll PM you.


Sent from my iPhone using Tapatalk

[John Z]

Dang. I winter in the RGV, and just drove by your place a week ago. I could have stopped and tried to help you out on my way North. Just give it time, you will learn a bit on each drive. Be patient on those upshifts, it takes a while for those big gears to mesh up. When I pull it out of gear, no throttle, it takes about a 5 count before its ready to go into the next gear. During the last part of that 5 count I have very slight pressure on the next gear and can feel it all as it gets close to meshing. Good luck.

[TomC]

Look at the YouTube VDO of Fred Rayman that RJ has the link. That is thee way to drive a 4 speed. Do NOT touch the accelerator when up shifting, as did on the other VDO. Just keep in mind, 8V-71's drop quickly in rpm's. Don't be slow on the shift.
Shifting a 13spd Roadranger in a truck isn't much different. I had 1.2 million miles on the truck and original clutch (never did a clutch job) when I converted it to the HT740 Allison. It is possible to shift without clutch, but would not suggest it on just a 4 speed-too big of gaps. When shifting, rev to the governor, then shift. Good Luck, TomC

[RJ]

Oh, here's a little bit of trivia related to the Fred Rayman video:

At the 3:50 mark, the gentleman sitting on the right as the cameraman works his way back is Larry Plachno, the Editor & Publisher of National Bus Trader, one of the bus industry's major trade magazines.

[HB of CJ]

After reading all the answers, maybe that straight truck truck driving school may be the best bet.  Respectfully, you are receiving conflicting information on how to shift your Cool 4106.  There are many different variables regarding shifting.  Grade, temperature, altitude, up hill, down hill, engine and tranny temperatures, even strong headwinds make a slight difference.

The key to it all is hours of experience and establishing that necessary mental-muscle memory and being able to subconsciously adapt for the aforementioned conditions outlined above.  Again, easy.  About the only way to do it is to have a pro lead you through it and then watch and make the corrections.  I for one have not driven a 4106 since 1970, but I am sure I could do just time.

How?  Mind-muscle memory and experience.  Like riding a bicycle.  A hundred things happen every second, but you are not aware of it.  Hope this helps.  HB

[Debo]

I guess I'll chime in too - just because I feel like it took me a while to get the hang of it. I finally found that gathering information from others was good, but my (and I suspect every) bus has its little quirks and ways it likes things done. What finally made me feel like I had it under control was to go on a couple of long trips with it once I felt like I could reliably go down the road without being a safety hazard. You'll be put in all kinds of situations that you have to work your way out of and you'll have plenty of opportunities to test different theories and ways of doing things. I have a tachometer, but have found that it's more of a "sound and feel" kind of thing for me. I guess my advice is to read up all you can, but then just drive it. On my bus, some of the ways I've read about doing things turned out to be exactly opposite of what my bus was asking for, and knowing that can really only be gained from experience. You'll get it.

[OneLapper]

Crazy heavy.  So heavy that my SO has to pull up on the steering wheel to have enough force to push down on the clutch pedal. 

Do a quick search on 4106 clutch on this forum.  Lots of info.

[Gordie Allen]

I had never driven a non-synchro 20,000# vehicle before and drove our 4104 from Sanford, FL to Augusta, MI. I used the clutch for all gears and avoided grinding 50% of the time. Once back home, I talked to a couple who are former truck drivers and now run my local hardware store. They said "just don't use the clutch." Saves a ton of work on your quads. Starting from a dead stop you have to use the clutch, but from there on I never use the clutch to shift up or down. It's all about matching the engine rpm with the tranny speed, basically driving with your throttle rather than the clutch. Much less work. Shifting up I let off the throttle while pulling gently on the stick until it falls out of first gently continue with a little pressure and it will fall into second. With an hour or less of practice you'll feel the rpm levels where the "sweet spot" is. Down shifting was more of a challenge. You let off the throttle while applying light pressure and it will drop out of gear immediately. Then, rev the engine above the rpm's you shifted out and then let off wait for the sweet spot to show up with slight pressure to drop it into the lower gear. If you miss, keep you foot off the clutch, rev it up to just higher than when you missed it and try again.

The MOST important thing to keep in mind is that you must slow down and get out of 4th gear and into 3rd BEFORE you begin a steep descent. NEVER start a steep descent in 4th. Once your engine is rev'ing at the limit in 4th, you have no way to get'er into 3rd without a lot of braking. I descend 5-6% grades in third at about 35 mph breaking when I get up to 45mph (47mph is the top of my 3rd gear rpm's) to bring it down to 35mph again. My biggest challenge was getting over going slow. I felt like I was obstructing traffic, but after a couple of long climbs, or descents out west, I found that there were plenty of heavy 18 wheelers going slower than me. Just put on your flashers and don't worry about the faster traffic. There ya go! Just one more opinion.

[andyps]

Andy -

I'd suggest you take it out this weekend to a nearby industrial park where 90% of the businesses are closed for the weekend to practice.  Lot less traffic in those areas.  Especially at 0800 on a Sunday morning!

The clutch can be heavy or really light, there's a whole bunch of factors involved.  First is proper adjustment, which actually, according to the book, starts up front and works it's way back.  At this point in time, it's not unusual to have a lot of slop in the linkage, slop that needs to be rebuilt to remove it and improve the clutch action.  Worst case scenario is the wrong clutch parts installed at some point.

Some folk may chime in and say put an Allison V-730 automatic in it, but if you enjoy the manual, it's a moot point.  Can be a PITA when trying to wiggle into some campsites perhaps, but that's why you scout out your parking site first.  It's also a PITA in heavy traffic (Dallas?  Los Angeles!), but if you avoid major commute times, that can be avoided somewhat.

OOOPS!!  Major mistake alert!

I just re-read my post to answer your question, and realized that what I said was bass ackwards to what I meant!

What I meant to say was that as you find the coach stabilizing and you can pull it out of 1st with the clutch out, bump the shift lever up against 2nd with the clutch OUT (not in!) and feel when it starts to drop into gear as the engine RPM falls off.  Immediately kick in the clutch so you can come to a stop and try it again w/o causing a lot of bucking of the drive train.  Be sure and LISTEN to the engine as you practice this, too.

Clear as mud?

FWIW & HTH. . .

Boom! That works!

Sorry for the slow update. Had a busy past few weeks and the bus is 45mins away in storage (until our yard is finished next week). Finally had time to get up there today and try out the shifting tricks. Did exactly what you said and on the second try I was shifting like a champ. Drove it around a big parking lot and then felt good enough for the open road. Used same technique (more or less) for all the gears.

In first, I put light pressure back towards neutral as the engine stabilized, pops right out into neutral. Wait a sec, clutch goes in and press back towards 2nd, slips right in! In second, pull back gently as I get to max revs, engine stabilizes, you can feel it wanting to move on to next gear. Clutch in, neutral, count to 2, clutch out, clutch in, pull towards 3rd and voila!

I was shifting all the way up to 4th easy peasy after about 30mins of practice.

I was so worried something was wrong with the transmission, but once I got to where I could feel what it was doing, it was smooth as silk! All those years of double clutching in my car paid off.

Thanks again for all the pointers! I am elated at the moment where I was previously frustrated. Excited to take it for another spin in a few days.

Now downshifting... haven't tried that one yet

Thanks everyone for your help!

[Barn Owl]

I spent a lot of time with a 13 speed spicer when I was younger. I had to give a guy a ride one time and half way through the trip he commented that he had never seen a clutch-less manual tranny (That was back in the day, I know things have changed). After enough miles under your belt you might one day get the same question. It did give me a good laugh though.

[IMABUSBOY]

 After I get moving, I only use the clutch at complete stops.
(Upshifting) Start off in 1st. At about 2300 rpm, as you let off the throttle. gently pull the shifter into neutral,(leaving the clutch out. This allows the tranny to match/sinc with the engine speed).  Leaving the clutch out. When the rpm drops to about 1500, gently slip the shifter into 2nd gear. Throttle down. Repeat for the rest of upshifting.

Downshifting: When down shifting just do the reverse. example: From 4th: Allow the rpms to drop to about 1500. Now you have to get the tranny up to match/sinc the speed that the engine 'will be going AFTER' the shift. (between 2000 and 2300 rpms)
To do this, (leaving the clutch out)
1. At about 1500 rpm, let off the throttle and shift into neutral.
2. reeve the engine to about 2100 rpm and as you let off the throttle again, you shove the shifter into 3rd.
3. Press the throttle. Away you go!

After a little practice you'll be a pro! Not having to press the clutch save your left leg going across the mountains. Good luck!
Danny

[chessie4905]

   Next need to practice going from 4th to 2nd as in slowing and turning at an intersection or a turn off to a side road. Btw, if the trans is like the 4104's, shift timing is faster when trans is cold compared to fully warmed up.