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Bus Discussion => Bus Topics ( click here for quick start! ) => Topic started by: 84dime on November 16, 2009, 01:30:59 PM

Title: Automatic 4104
Post by: 84dime on November 16, 2009, 01:30:59 PM
Just wanted to know if i could keep the 6-71 but install a automatic transmission. I do not drive it that often but i hate double cluching or grinding gears. But then again mabe im just a punk 22 yr old kid that needs to suck it up  ;D
Title: Re: Automatic 4104
Post by: Melbo on November 16, 2009, 01:35:58 PM
I don't know if you can keep the 6 71 and add an auto but I understand about the grind thing.

My girlfriend hated the grinding so in and about everything else I did on the bus an auto was in the works.

Hope you can make it all work

Melbo
Title: Re: Automatic 4104
Post by: 84dime on November 16, 2009, 01:44:38 PM
It would be no problem if the transmission was syncronized
Title: Re: Automatic 4104
Post by: gus on November 16, 2009, 03:05:41 PM
Even though I had driven a bunch of older heavy trucks including some 18 wheelers the 4104 trans got the best of me at first.

Now, after three years I finally got it figured out so that I only crunch gears once in a while.

I don't use the clutch going up except when starting out from a dead stop. The secret is in waiting before shifting into the next higher gear. It took me a long time to master this since I'm not a very patient person, but it is absolutely necessary.

Going down in gears when climbing hills the secret is to shift via a double clutch as fast as you can without lifting your foot from the throttle. And I do mean fast, as fast as you can do it. I learned this technique from reading this board.

All this presumes that you have the clutch and shifting rods adjusted properly. If you don't it will never work well.

The whole procedure is in the manual. If you don't have a manual, get one. Two actually, you need a parts book if you do any of your own maintenance.
Title: Re: Automatic 4104
Post by: 84dime on November 16, 2009, 03:29:43 PM
Actually i was going to post about that. Where can i get a manual? I have looked but nothing. Thanks-Josh
Title: Re: Automatic 4104
Post by: wildbob24 on November 16, 2009, 03:41:34 PM
Josh,

eBay can be a source. Also, there's an advertiser on this board that has them:

http://www.coachinfo.com (http://www.coachinfo.com)

Bob
Title: Re: Automatic 4104
Post by: 84dime on November 16, 2009, 04:11:51 PM
Thanks Bob, will have to get manuals soon.
Title: Re: Automatic 4104
Post by: RJ on November 16, 2009, 06:17:22 PM
Quote from: 84dime on November 16, 2009, 01:30:59 PM

Just wanted to know if i could keep the 6-71 but install a automatic transmission. I do not drive it that often but i hate double clutching or grinding gears. But then again maybe I'm just a punk 22 yr old kid that needs to suck it up  ;D


Josh -

Yup, you gotta suck it up!   ;D ;D ;D ;D

Seriously, if everything's adjusted properly, the 4104 is actually pretty easy to shift, almost like a VW Beetle.  It just takes practice.  So, to help you practice, start here:

http://www.busnut.com/bbs/messages/12262/16204.html?1167073154 (http://www.busnut.com/bbs/messages/12262/16204.html?1167073154)

Print it out and take it along with you on a drive to practice, you'll be amazed at the difference!  BTDTWTA.

Now, to answer your original question - yes, you can install an automatic with the inline 6-71, however, three major problems - engine's too long, gutless as heck, and drive line angles don't work.

The only really successful auto installation is a 6V92TA/V-730, coupled with a rear axle out of a 4106 and later GM.  If you don't use the later rear axle, you'll tear up driveshafts, due to the angles.

Nowadays, it's not economically feasible to do such a swap with a 50 year old coach, better to learn to drive as is, or sell and buy a coach w/ an auto.

BTW, PD4104-3946 was delivered new as fleet number 39 in April of 1959 to Frank Martz Coach Co, based in Wilkes-Barr, PA.  Martz is still around, one of the better independent carriers still to this day.

FWIW & HTH. . .

;)
Title: Re: Automatic 4104
Post by: TomC on November 16, 2009, 07:35:11 PM
Because of the length of the 6-71 engine, there really isn't enough room to install an automatic (the 6-71 transits that had automatics were 102" wide compared to the 4104's 96" wide).  About the only conversion to automatic has been using either a 8V-71 or 6V-92 with V730 that I've seen.  Personally- a 6V-92TA with V730 would really make the 4104 a hot rod.  Good Luck, TomC
Title: Re: Automatic 4104
Post by: 84dime on November 16, 2009, 10:56:17 PM
Hey guys thanks for the replies. I am going to read what RJ posted and try that. Thanks again.
Title: Re: Automatic 4104
Post by: WEC4104 on November 17, 2009, 05:05:02 AM
Joshua:

When I first got my 4104 (10 years ago) I was a bit intimidated by the manual transmission. I had never had any difficulties with a variety of stick shift cars or trucks, and I found the 4104 to be quite the challenge. In the first year or two, I often contemplated a change to an automatic. From reading here and elsewhere, I learned that the conversion to an automatic would require a repower and most likely a change of the rear axle.

As years have passed, and the trips in the bus have piled up, the desire to change to an automatic steadily moved lower and lower on my list of bus priorities. My shifting skills have improved a tad, but are still far from perfect. Just when I start feeling real good about myself, the Spicer finds a nice way to knock me down a peg or two. I may never conquer the Spicer, but it is like we have come to some mutual understanding. 

Today, I have zero desire to convert my 4104 to an automatic. In fact, if someone found a magical way to drop an automatic in next to my 6-71, and could do it for next to nothing, I wouldn't do it.  The reasons go beyond the automatic sapping power and fuel mileage.  For me, the manual shifting has become part of the bus' personality.  It reminds me that I am not just driving a really large minvan.  As a driver, it mentally engages me and adds to the whole twisted experience.

Joshua, my advice is to get in and drive.  With more miles you will get more comfortable, and the Spicer will grow on you.....  and that desire for an automatic will fade.
Title: Re: Automatic 4104
Post by: 84dime on November 17, 2009, 08:47:11 AM
Hey thanks WEC4104, I think you are right. I was thinking of putting caps on it and smoothing it out and then i stopped and thought to myself (man it will just look like a newer coach and i dont like that, and thats the reason for buying this bus) So i guess the more changes i do to this thing the less cool it will be ;D
Title: Re: Automatic 4104
Post by: TomC on November 17, 2009, 02:50:07 PM
Personally- I love the looks of the 4104.  The only thing I would do would be to put a smoke turbo on the engine so you can maintain most of the power when in higher altitudes.  While 25 mph going up long grades was acceptable in the 60's, most trucks now are doing 35-40mph on long grades.  The turbo (mount it right above the transmission) would be the choice to get a bit more oomph out of it.  Good Luck, TomC
Title: Re: Automatic 4104
Post by: gus on November 17, 2009, 07:39:49 PM
84,

Don't change the looks. As you say, why look like everything else on the road when you have something really unique. I love those silver sides.

I looked a long time to find one with no windows covered and no caps. Original is cool! Mine looks about like it did when Trailways had it, even the trim is the same color but not exactly the same design. I even plan to eventually put Trailways lettering on it.

Same thing for the interior, make it look the same era as the bus not the modern beige leather and blond furniture, that looks really odd on a 50 yr old bus.