47re Clutch Pack Upgrades

Ok thanks for the info. I bought Raybestos clutches, both the thin and thicker ones. The thinner clutches still have the groves like the thicker ones only they are very shallow and harder to see but they are still barely there. They were just less than 4 bucks apiece. I will play around with the plates, steels and frictions and see what I can come up with. I think I can come out with 6. I will post how everything turns out.
 
maxedout03 said:
Also what do you set the clutch pack clearences to with extra clutches added? Do you set them a little looser or not?
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I modded my direct clutch pack today with four .065 clutches, two .085 clutches, and six .070 steels. This gave me right around .070 clearance. Brad Ponci said in an old thread that he likes .060-.080 for clearance in the direct clutch pack and .025-.035 in the forward clutch pack. He's built enough of these transmissions that I feel comfortable heeding his advice.
 
Nice write up man, i was planning to do one when i built my tranny last summer but didnt have the time due to my wedding. I do have a bunch of pics from the build though...

Do you block sand the valve body to case mating surface? Or lightly sand the apply piston recesses?

Did you check for proper thrust spacer/bearing clearance in the OD section? That was one of the trickier parts of my build, especially since i had to replace a few hard parts and use cases from different trannies.
 
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mathews8pt said:
Nice write up man, i was planning to do one when i built my tranny last summer but didnt have the time due to my wedding. I do have a bunch of pics from the build though...
You should start a new thread and post pictures and explanations of your transmission build. I'd like to see some of the methods, tips, and tricks you came up with during your build

Do you block sand the valve body to case mating surface? Or lightly sand the apply piston recesses?

No, everything was straight and true.

Did you check for proper thrust spacer/bearing clearance in the OD section? That was one of the trickier parts of my build, especially since i had to replace a few hard parts and use cases from different trannies.
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Yes, however this thread was not started to teach how to perform basic tasks required for a general transmission rebuild, the purpose of this thread is to show pictures of upgraded clutch packs, explain how to gain clearance for the upgrades, and explain the general function of each clutch pack/band.
 
Hey guys I just rebuilt my trans and its not going into drive only reverse so I took it back apart and There are a couple things that caught my eye. The input shaft is two piece, and where it mates with the hub, there is a wire ring that is supposed to help lock it in place. That ring kind of kicks out at one end, and I don't know how much effect that could have on it if any. Also many of the rolle rs in the overrunning clutch are sticking. They are sticking free wheel position though so I am not sure if that would cause an issue....? Anyone got any ideas?
 
dipapadakis said:
Hey guys I just rebuilt my trans and its not going into drive only reverse so I took it back apart and There are a couple things that caught my eye. The input shaft is two piece, and where it mates with the hub, there is a wire ring that is supposed to help lock it in place. That ring kind of kicks out at one end, and I don't know how much effect that could have on it if any. Also many of the rolle rs in the overrunning clutch are sticking. They are sticking free wheel position though so I am not sure if that would cause an issue....? Anyone got any ideas?
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Find a reliable trans shop that's local to you. They will be able to help more effectivly. I would probably just have a shop do it after my bad experiance trying to do my own.
 
Big Blue24 said:
Forward Clutch Pack:
- This pack is located right behind the input shaft hub.

*snip*

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


*snip*
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This fitment issues can be avoided by buying snap ring for GM TH400 center support for less than $8 from wittrans.com

"You will need a snap ring from a GM TH400 center support to replace the wider original snap ring. (TSR Racing Products)" Page 172 Munroe Carl H.; Torqueflite A-727 Transmission Handbook, August 2003

I have a basket full of disassembled TH400 that I used to steal parts from to build my other TH400 so I can't tell exact name or part # is the right one. I tried my best and came up with 2 different snap rings thats from the center support and one of them is nearly identical to the stock snap ring from my 47RE, while the other one is much thinner and is the one that this book stated to use to fit the different pressure plate.

everyone love pictures right? :hehe:

the top is the stock 47RE snap ring, center is the incorrect (but very similar to the stock 47RE snap ring and you don't need this) and the bottom one is the correct snap ring from TH400 center support.

DSCN3244.jpg


Picture shows TH400 center support snap ring and the forward pressure plate installed. I couldn't slip in the stock snap ring, its too tight to pop it in quick to take a pic.

DSCN3247.jpg


https://www.wittrans.com/SchematicParts.aspx?Transmission=400&LinkCode=883

Part # 34883 if link don't work

https://www.wittrans.com/SchematicParts.aspx?Transmission=400&LinkCode=872

Part # 34872 if link don't work

let me know if you can tell which one is the right one and I'll edit this post.
 
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Your stepped pressure plate is installed on the wrong side. The stepped Plate towards the belville spring side. The flat plate at the snap ring side.
 
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Oh, I get it. I had brain-fart. This is how it's suppose to be. There are stepped plate on bottom, the one in top is one that I bought to replace the flat thick pressure plate to increase clutch count.
 
Is there a advantage to running the new style forward bevelle return spring? I have both and the trans is tore down on the table.
 
The new style spring is supposed to be a little tougher. If you have a set of calipers and camera, take a few thickness measurements and post up what you find.
 
I believe that the new style spring is supposed to be used with the new style piston, and the old style spring used with the old style piston. Been awhile since I have had an old style trans apart though.

I have also heard that the older style spring is supposed to be better LOL. So probably one of those things that depending who you talk to I guess. I does appear that the newer style will allow a little more travel, before it permanently collapses.
 
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