727 yoke wont come out. What's the trick ?

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C300

C300

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This is from a class C (big 1973) motor home. 440 +727, 2 carrier bearings N slip joint drive shaft. Do i need to pull the cap off the center of the yoke ? or is this just rusted in ?!?
 

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This is from My 1 ton. I just rebuilt it. Short shaft with bearing instead of bushing. I think this would be better and stronger than the slip joint. always wondered why is wasn't used in performance applications.
 

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This is the tail shaft i have and want to install on the BB 727 in the first Picture. 18 1/2" from end to end. Is this the "normally used one" ? I don't want to have a drive shaft made then have the non standard one. thanks, C300

67' Barracuda. 440 block spool mounts.
 

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Popping the cap will not achieve anything, except to give you access to lube the splines, and something to have to repair later.
A)I cant imagine the splines to be rusted to the yoke.
B)I can imagine that the yoke is too far into the tail and has run up onto the unsplined area of the output shaft. A couple of taps with a metal hammer should knock it back off.
C)its also possible that the yoke at one time welded itself to the bushing, broke loose and now is stuck in the grooved section.
In A and B above, the yoke and shaft can be moved back and forth, to the extent of the M/S endplay,maybe as much as .030
In C above,the yoke will move only a few thousands
If I had to guess, Id go B. Good luck.

If youre thinking of converting that motorhome tranny to street duty, you will be wanting to make other changes as well.I cant imagine the VB will be right, and Im sure the governor will be wrong, and the input better match your chosen convertor, and the TC better fit your crank.
 
It "should" just pull off. It's either rusted, or years and years of abuse from the mass of a ship of a motorhome have damaged the splines. You may have to drive it off.

On your example with the nut retained yoke, all you've done is move the slip yoke function to a component in the drive shaft. This may or may not be better LOL

I can't tell from your tail housing, "what you have" So far as I know there is only one long shaft 727.
 
thanks guys, i did try to "knock" the "if it is a" slip yoke off. bronze mallet, 28oz ball peen and 1" brass drift, BIG slide hammer. though i'd ask before heating and beating, lol
the tail shaft from the motor home is slightly different. if you notice the aft bottom end near the slip joint, it's milled flat and tapped for 2 bolt holes. presumably for support during hi torque. ever break a tail shaft ?!? this trans does have a 4 gear planetary setup. thrust washers are worn down to base metal in spots. some heat coloring too. it did get some use !!! see if some heat will get it. i did lift the seal and shoot penatrating oil in there last weekend. thanks again
 
On your example with the nut retained yoke, all you've done is move the slip yoke function to a component in the drive shaft. This may or may not be better LOL

I was also thinking that a Bearing, as apposed to a bushing, would have less friction, causing less heat. should take a bigger load too. All the PRO trans replace bushings with torrington needle bearings and ball support bearings. See PATC trans Low Drag geartrain assy.

http://www.transmissioncenter.net/727transmission.htm

Would be nice, but at $795.00 maybe thats why...
 
Got it off with a little hyd. pressure. now i just have more questions! ever seen this ? the other shaft is from a BB parts trans. same splines. looks like this one was cut off or ground for some reason. maybe it shattered a joint/yoke in the past and someone cleaned it up ? anyone seen this or done this ? Motorhome special ? is this shaft serviceable ? or use one of the others i have. got 2 more, one from a BB and one from a SB. they the same? the 440 based 512 should be somewhere just above 600hp. says Hughes. this yoke has 5 1/2" of splines in it. looks to be in good shape. no damage. Drivelines NW said they include a new yoke with the new drive shafts. No cheapy parts.
 

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Looks like somebody thought it would be cheaper/easier/whatever to shorten the M/S rather than the driveshaft.
That yoke should be sticking out the back around 3/4 inch.
I guess it will need to be changed
EDIT oops , I see it is sticking out
 
Man, I don't know. Maybe a swap with a too long shaft. That cut might explain why the yoke was tight= cut off and burred up splines
 
Someone was to cheap to have their driveshaft shortened and instead decided to remove more of the output shaft holding the slip yoke out, which is why that is like that.

As for your question... what makes you think or feel the bolt on end yoke is stronger ?
 
AJ/FormS, Must have been B). kinda popped loose on the press. Thanks for your input ! The crank is a 4.25" stroke Eagle forged 8 bolt unit. will be using a trans brake rear band apply VB. 3200-3400 stall converter. yes, I'm building it from the back to the front. have a 410 dana 60 and a 373 8 3/4". shortened both, tubbed. looking for 3.55's. S/B the best for the street. just the gears for shipping purposes. if i can get a whole diff. local i will. Lots of aftermarket parts for the trans. lowering 1st with planetary to match the cam with the 3.55. anyway, thanks
:coffee2:
 
The bolt on yoke requires a slip joint to be in the driveline (like a motorhome) :D
 
Supershafts, just like the bearing. If there were 2 like an upper box in an out drive ( boat) or jet engine it would be less friction. Way smoother and cooler operation. Overkill probably for the cost. Yes trailbeast, it would need a slip joint. Not sure that's allowed by nhra. Unless two bearings were in a sleeve in the tail shaft. Again costly. But I'm sure it is worth 5-10 hp. If not more. Last forever too!
 
Also, the pro trans. Have 2 bearings. The stock one and add one in the carrier. The one ton has the second one in the back, instead of the bushing. From towing heavy *** loads uphill, the carrier, aluminum, got hot, expanded and galled and got stuck to the shaft. That's why I rebuilt the trans. Used the carrier from the parts trans. Stuck the shaft on the lathe and removed the aluminum. Figured I'd do the Cuda trans and get it out of the way. Seeing as I found a problem, just looking to not repeat it...
 
If you swap the output shaft (and I would) make sure and use the correct output shaft to match the front planetary gear set your using. A 66-75 output shaft with a slip yoke is the one that you need if you use the planetary gear sets from the motorhome. You can't tell the difference with the naked eye but the front splines on the output shaft are cut at a slightly different angle on the different year spans so you have to use the matching vintage front planetary gearset for the output shaft. If your not sure what year the output shafts you have are here's a picture to identify them
 

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Yeah, I found that out the hard way. Ziiing, no mo locomotion.
And you are right, you cant tell with the naked rye. Not even with a magnifying glass.

But hey, since you know and understand about that problem, and have those great m/s pics, which clearly show the code system on the rear ends of the shafts; do you also have pics of the matching planrtary code system. I have parts to build at least 6, 904s, but am afraid to put them together for fear of warranty returns due to this exact problem.
 
AJ/FormS said:
Yeah, I found that out the hard way. Ziiing, no mo locomotion.
And you are right, you cant tell with the naked rye. Not even with a magnifying glass.

But hey, since you know and understand about that problem, and have those great m/s pics, which clearly show the code system on the rear ends of the shafts; do you also have pics of the matching planetary code system. I have parts to build at least 6, 904s, but am afraid to put them together for fear of warranty returns due to this exact problem.
Click to expand...

I haven't ran across anything on how to identify planetaries. Keeping my eye out for something and if I find it I'll let you know.

BTW: are you sure the m/s splines apply to 904's? Everything I've read talks about it applying to 727's but 904's aren't mentioned and when I look up planetary gear sets for 904's they don't have a year break in 76 like 727's do. The only break I see is when they went to the 5" o.d. ring gear
 
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