47re Clutch Pack Upgrades

akadiesel said:
None won't work, for sure. Reasons for none: too thick thrusts between shafts, drums & pump, direct not all way in shell, and maybe more. Maybe pump not fully in, so sealing rings not working? And fluid not directed right.
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TCS Direct drum is .022 larger than OEM drum.. So that was why there was zero end play..
 
To me, the only reason for zero, negative, or too much end play is that the builder either didn't check it or failed to correct it. If there weren't known variations in even new parts, there would not be a need for selective spacers and snap rings. The minimum end play I ever saw desired is .010 in a race trans.
 
With the Direct clutch pack on mine it has 9 return springs in it for the pistons with places to add 6 more to it to send it up to 15 springs. With the increased spring count could the clearances be tighter? I heard some people running them as tight as .030 for a street beater. Any thoughts?
 
rlawless-good pics & picking up what I was trying to say. 3rd pic shows shaft too high, assuming you kept hole in retainer on the same center. I will go into possible reasons shortly, as you aren't here now & I just lost 30 minutes of typing it out. Number of springs should not affect end play.
 
akadiesel said:
3rd pic shows shaft too high, assuming you kept hole in retainer on the same center. Number of springs should not affect end play.
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The 3rd pic was the best I could get it to center and that was with the smallest shaft spacer available... I did grind one spacer down thinner but, Then the anulus would have been riding on the piston retainer again... I dropped the tranny pan to make some pressure adjustments and I'm still getting aluminium shavings in the pan and I can see metal flaking in the ATF... I don't get it!! Something is wrong for it to still be wearing on the piston retainer..

Edited: Not sure why your comment about the "Number of springs should not effect end play"
 
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OK, assuming you kept hole in retainer on the same center, and using the smallest spacer available, it would be nice to not see either race. Some shops, incorrectly, press od while in od case & deform clip that holds od in its case. This can lower od in case & top race would show. Flipping clip over can correct this sometimes, but can also raise od & shaft. I have seen that with different output shafts, using all other same parts, that instead of spacer on tail end of shaft riding against od planet, the shaft is riding on output. If you pry spacer to the rear, grease end of shaft & next landing, then insert shaft, you can see where it is hitting. If spacer didn't move and grease flattened, then spacer isn't against planet & play there. A thicker spacer would be needed, but this would raise shaft more. I really don't know best solution here, but I am looking at one here. Any input appreciated. I see that you have good clearance from the ring gear anulus housing and the piston retainer, but is this a new housing or the one that may have had wear where it sits on shaft? I don't know the clearance needed here, but would like to. Since you opened up the retainer hole, and even without, enlarging shaft holes 30% or so ( like Alto shaft) will help flow. Is tranny in yet?
scat-.030 is about where I set clearance for four clutches in forward pack. Most seem to think .012 to .015 clearance/clutch in direct. I do .060 for 4, .065-.070 for 5. It looks like rlawless is running 7 & wonder what clearance? Too little & they won't get fluid between when not engaged, but too much & piston would travel too far? I know what clearance I'd use, but wouldn't advise others how to go when extreme. Just remember its per clutch & I can't imagine .030 per assembly lasting.
 
Edited: Not sure why your comment about the "Number of springs should not effect end play"[/QUOTE]

That was answer to scat's question.
 
akadiesel said:
OK, assuming you kept hole in retainer on the same center, and using the smallest spacer available, it would be nice to not see either race. Some shops, incorrectly, press od while in od case & deform clip that holds od in its case. This can lower od in case & top race would show. Flipping clip over can correct this sometimes, but can also raise od & shaft. I have seen that with different output shafts, using all other same parts, that instead of spacer on tail end of shaft riding against od planet, the shaft is riding on output. If you pry spacer to the rear, grease end of shaft & next landing, then insert shaft, you can see where it is hitting. If spacer didn't move and grease flattened, then spacer isn't against planet & play there. A thicker spacer would be needed, but this would raise shaft more. I really don't know best solution here, but I am looking at one here. Any input appreciated. I see that you have good clearance from the ring gear anulus housing and the piston retainer, but is this a new housing or the one that may have had wear where it sits on shaft? It's the original, I didn't see any wear, just the hot color ring.. I don't know the clearance needed here, but would like to. Since you opened up the retainer hole, and even without, enlarging shaft holes 30% or so ( like Alto shaft) will help flow. Is tranny in yet? Yes Tranny is in.. See above #108 comment..
scat-.030 is about where I set clearance for four clutches in forward pack. Most seem to think .012 to .015 clearance/clutch in direct. I do .060 for 4, .065-.070 for 5. It looks like rlawless is running 7 & wonder what clearance? Can't remember clearance used but it was within the clutch power pak specs.. wrote it down in manual which is not with me.. Too little & they won't get fluid between when not engaged, but too much & piston would travel too far? I know what clearance I'd use, but wouldn't advise others how to go when extreme. Just remember its per clutch & I can't imagine .030 per assembly lasting.
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All my clearances are within the specs with the power pak instructions... I didn't want to be to close cause it's a DD..
 
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REAR ANNULUS GEAR looked to have wear where it sits on shaft. And it was rubbing od retainer above that. But pic shows you have clearance there now. I know it's hard to tell everything you've done, but you'd think it would rub worse with thinner spacer. Did you do anything in od that would have raised shaft?
 
Looking further into od, intermediate shaft pilot bushing was either not pressed in far enough or burred, keeping shaft from going in all the way. When replacing pilot bushing, make sure the next step on shaft bottoms out & shaft turns free. Now spacer can work right.
 
zstroken said above: Goerend mentioned a similar issue. I have seen 48RE annulus gears without the holes drilled into them. I've not built a 48 trans, so don't know if 47 annulus will work. I enlarge shaft holes & turn up the pressure on my trannies. For sure, just replacing thrust washer ain't no solution!
 
Big Blue24 said:
Forward Clutch Pack:
- This pack is located right behind the input shaft hub.
- Stock 47re has (4) frictions
- Stock 48re has (4) frictions with a different spline count so if you buy a 48re rebuild kit just remember to buy extra clutches for this pack that don't have the 93 center splines like the 48re clutches.
- This pack is applied in all forward gears and it's not a shifting pack so it's not subject to as much wear as the other packs.
- This pack is released when the transmission shifts into reverse.
- This pack is the most difficult one to upgrade since space is very limited.

I upgraded this pack from (4) frictions and steels to (5) frictions and steels for 25% increase in clutch capacity by purchasing a used forward clutch pressure plate and using it as a stepped reaction plate. This drums snap ring groove is machined a little tighter than the direct drum and it's nearly impossible to install the snap ring without grinding a little bit of the inner corner so the plate has a wider flat stepped portion for the snap ring.
11-30forwardclutch.gif


The arrows point to the small corner than needs to be ground just a little to gain clearance for the wide snap ring. I just used a 4-1/2" grinder with a 1/8" thick metal cutting wheel and slowly made an approximate 0.030" deep cut and worked my way around the entire pressure plate. It is possible to install the snap ring without grinding the plate but makes the clutch pack a little tight which would cause it to drag a little in reverse, not a good idea for a daily driver that uses reverse regularly but running an unground/unmodified pressure plate hasn't been a problem for my drag race truck.

ForwardArrow.jpg


With increased line pressure, this pack seems to do fine with the stock (4) clutch count in 47re and 48re on diesel applications up to about 500 HP rear wheel horsepower, after that it's probably a good idea to upgrade this pack.
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zstroken said:
Note that you also have the older style return spring.
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This may be a dumb question, but what is the difference between the old and new style return spring?
 
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