4104 vs 4106 Rear Axle Pumpkin Help

RJ · October 10, 2015, 10:15:24 AM

Have a question for owners of the above model coaches that still have the original powertrains.

It's going to take a tremendous amount of work to get the answer, thus put on your coveralls and dig out that big flashlight so that you can take a look. Best observation will probably be on your belly at the front of the bus centered under the breastplate looking towards the back bumper. Very grueling, so prepare accordingly!

The question:

Which side of the coach's longitudinal centerline is the rear axle pumpkin? Streetside or curbside?

When you answer, please respond with coach model and side, like this example: 4104, curb.

The answer will help a fellow busnut try to sort out a vibration problem.

TIA. . .

4104SoFl · October 10, 2015, 10:31:10 AM

4104-1889 1956 Street Side

Darkspeed · October 10, 2015, 12:28:46 PM

1961 4106 = 4" offset to Curb side from centerline.

Red Rider · October 10, 2015, 03:53:34 PM

4106 1885 curb

uncle ned · October 10, 2015, 04:51:35 PM

I believe the difference is in the angle of the pumpkin not in the side of of the coach it resides on.

Hardheaded Ken will sneak in here soon, but I remember Jara Smith reworking the inside of the axel on a 04 and then putting a o6 pumpkin in.

uncle ned

my 04 with 6v92 and v730 is curb side i am almost sure raining to hard to go check

OneLapper · October 10, 2015, 09:15:40 PM

I have a 4106 axle sitting on a pallet. LMK if you need detailed pictures or measurements.

luvrbus · October 11, 2015, 07:58:35 AM

You can install the 4106 pumpkin in the 4104 housing by enlarging the notch for the larger ring gear from the 4106 but I don't think that solves the problem I seen people try to take some of the angle out with the angle on the engine on install.
I seem to recall the degrees of 57 and 63 but forgot which is which for each bus maybe Ken remembers

RJ · October 11, 2015, 09:57:50 AM

Thanks all for your help. Appreciate you all taking the time to take a look for the answer.

RJ

Darkspeed · October 11, 2015, 12:20:28 PM

Just measured mine on the 4106 and it seems to exit around 55 Deg... could be 57 Deg...

chessie4905 · October 11, 2015, 03:29:23 PM

Does anyone know if a 4104 diff will fit into a 4106/4905 axle housing? Luke doesn't know, as I asked him.

TedsBUSted · October 26, 2015, 06:46:07 PM

This is from memory, so some details may not be perfectly clear.
What I am certain of is that I once installed an '04 pig in an '06 housing so that an '06 could drive in under its own power. It definitely worked. I drove the coach in myself.

As I recall both '04 and '06 diffs were curb side located.

I believe that the '04 pinion-mounted parking brake (drum, etc.) had to be tossed for lack of clearance. Pig bolted in without grinding, cutting, etc. Tools for "machining" were not available roadside.
I do not recall changing side-gears, axle-shafts, pinion-flange or drive-shaft; all of that matched and was workable.

Not exactly clear on this, but I do recall some light "rework" of aluminum bulkhead for drive-shaft clearance. However, the rework to the bulkhead possibly was necessary due to previous damage caused by the diff failure, or something else. Whatever it was was not too big of a deal.

THE PINION ANGLE WAS WRONG and drive-shaft's working angle was not right!!
This worked for 300 or so miles needed to get a bus off of the road but would not have been workable long term.

Hope it helps

chessie4905 · October 27, 2015, 04:34:57 PM

Reason I ask was toying of installing a 3.55 rear into a 4905 and use large cv joints instead of u-joints on the short drive shaft There is a company that makes about any size and capacity cv's.Team this up with 400 hp 8-92 with V730. I don't know if 8-71 would have the needed torque for starting out on a grade.