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Bus Discussion => Bus Topics ( click here for quick start! ) => Topic started by: bevans6 on November 01, 2016, 01:54:25 PM

Title: Allison install driveshaft and adaptor questions
Post by: bevans6 on November 01, 2016, 01:54:25 PM
Hi guys, update time.  My new flexplate has arrived so I need to make a crankshaft flange adaptor.  This is a simple spacer about a half inch thick with holes for the crank bolts and registers for the OD of the crank flange and the ID of the center hole of the flex plate, and a register for the pilot of the torque converter.  I have a nice chunk of billet 6061-T6 aluminium - I know these are normally made from steel, but is there any reason why this couldn't be aluminium?  It's really just a spacer, the way I see it.  The aluminium is left over from when I used to make car racing flywheels.

Second question - I am looking to put together a driveshaft.  The spicer catalog has the part numbers I need, but the supplier websites show the ones I want as obsolete.  Are all the 2.5" 16 spline shafts and sleeves pretty much compatible with each other so I pick ones that end up with the length I need?  I am looking at 1" shorter collapsed length than actual minimum length, so there some extra compression available.  Is that right?  Does anyone have a good driveshaft shop I could call for advice?

Thanks, Brian
Title: Re: Allison install driveshaft and adaptor questions
Post by: Jim Eh. on November 01, 2016, 01:59:32 PM
Try giving Pat's Driveline a call in Alberta. Maybe they have done a few oddball ones for the oil industry? http://www.patsdriveline.com/index.php/products/driveshafts.html (http://www.patsdriveline.com/index.php/products/driveshafts.html) We have used them for some crane driveshafts in the past. Sorry no fresh contacts.
Title: Re: Allison install driveshaft and adaptor questions
Post by: luvrbus on November 01, 2016, 02:23:55 PM
I think they use steel for the hub because of the heat generated by the torque converter,maybe cover the aluminum spacer with a scuff plate from the steel hub it would be ok I don't know for sure 
Title: Re: Allison install driveshaft and adaptor questions
Post by: brmax on November 01, 2016, 03:01:24 PM
the aluminum would no doubt change faster than the steel and a number of times.
I think the permatex anerobic grape jelly sealer is considered but I rather see ya use steel, somehow.
Either is a task
do you have a couple numbers for the splined shaft, one part you have and other you would like.

Floyd
Title: Re: Allison install driveshaft and adaptor questions
Post by: chessie4905 on November 01, 2016, 03:36:10 PM
This is one location I would only use steel for. Do you also have two holes that are doweled? Need to extend the dowels to reach through the adapter or drill and tap those two holes for bolts. Maybe the dowels are only on the 6-71. Too tired to drag out my manuals and look. You could Google a search for other opinions on using aluminum for flywheel spacers.
Title: Re: Allison install driveshaft and adaptor questions
Post by: kyle4501 on November 01, 2016, 07:10:33 PM
I haven't seen many, but they were all high quality steel. Mine was thru bolted to the crankshaft & tapped for the flex plate discs to bolt to it.

If you think about the power being applied thru that connection. . . . I would think that the crank adapter is one place you wouldn't want to have an issue.

Aluminium is softer, so it's load carrying capacity won't be as high.
Title: Re: Allison install driveshaft and adaptor questions
Post by: bevans6 on November 02, 2016, 06:21:15 AM
I've been able to decode the Spicer part numbers (a little bit at least) and I'm getting a Spicer 6-3-2671KX Yoke Sleeve, and a Spicer 6-82-1171-13 Yoke Shaft.  These two parts should, according to the diagrams, come up with a centerline to centerline minimum length of 13.32" and a maximum length of 16.18".  The flange on one end adds 2.5" so the over-all lengths should come out at 15.82" to 18.68".  My overall installed length will be 17", so this puts the shaft in the middle of it's engaged range, with 28 degree operating range.  The sleeve is apparently a very common part, but the shaft has to come from California (if it's in stock).  I now know a lot more about close-coupled driveshafts than I did two days ago... including that a lot of the part numbers in the Spicer catalog are obsolete.   And they are not cheap!  This driveshaft is going to cost a lot of money. 

Brian
Title: Re: Allison install driveshaft and adaptor questions
Post by: luvrbus on November 02, 2016, 07:55:19 AM
I recall mine was 1000 bucks in the 90's,your modulator and cable is supposed to be delivered today but I haven't tracked it
Title: Re: Allison install driveshaft and adaptor questions
Post by: bevans6 on November 02, 2016, 08:14:32 AM
Clifford. it shows as on the truck, out for delivery, so it should come today.  I am hanging around so I can pay the duty/brokerage fee.  Thanks again, every little bit helps!

Brian
Title: Re: Allison install driveshaft and adaptor questions
Post by: bevans6 on November 02, 2016, 01:07:50 PM
Cable arrived safe and sound, thank you very much.  I sent you a PM also.

Brian