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  #21  
Old 03-19-2009, 05:22 AM
jakeshoe jakeshoe is offline
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Default Re: 200-4R Rebuild ... step by step!

Now the low support can be installed. There is a feed hole and wide spline. This faces the valve body or bottom side of the case. This is best accomplished using a support installer/remover tool as shown but can be done by other means.





Now the beveled snap ring needs to be installed to hold the low support housing in place.
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  #22  
Old 03-19-2009, 05:24 AM
jakeshoe jakeshoe is offline
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Default Re: 200-4R Rebuild ... step by step!



Next we install the sun gear and shell.


And then the front sun gear,
same as before, grooved side down.



Then the input ring gear, thrust, selective, and snap ring.
Then the foward selective. It goes between the forward drum and output shaft.
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  #23  
Old 03-19-2009, 05:27 AM
jakeshoe jakeshoe is offline
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Default Re: 200-4R Rebuild ... step by step!

These are numbered. Higher number is thicker for less endplay.

I usually start with a 8 or 9.




Now
we can take out forward drum subassembly (left) and direct drum assembly (right) and assemble them together to prepare to drop them in.


Install the thrust washer on the front of the forward drum:


Set the direct drum on the forward and rotate, wobble, spin, until it drops all the way down. It is often easier to flip the drums over and feed the forward down into the directs.
When properly seated it should make a thud sound and look like this
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  #24  
Old 03-19-2009, 05:30 AM
jakeshoe jakeshoe is offline
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Default Re: 200-4R Rebuild ... step by step!

Note the machined direct drum surface, this is mandatory with a new wide band.

Install a new band, preferably an Alto Red Eagle Wide band.


Then set the forward and direct drum onto the input ring gear, aligning the cutouts on the direct drum with the lugs of the sun shell at the same time. Spin until it all seats but don't let the direct drum become unseated on the forward drum.
You can carefully use a pr of vise-grips here to hold it and spin it. Don't damage the splines on the forward drum...

Note,
You can get the band in after installing the drum assemblies, but I've found it is usually easier to ease the drums by the already installed band BUT do so carefully, don't be too rough on the band.
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  #25  
Old 03-20-2009, 03:58 AM
jakeshoe jakeshoe is offline
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Default Re: 200-4R Rebuild ... step by step!

Next install the sealing rings on the center support. These are usually iron rings. I use teflon. Notice the 2nd ring is omitted. This is part of the dual feed mod also used on TH350s and TH400's. Install all three rings unless the trans has a improved forward drum.



Install the thrust washer on the back of the support.



New lip seals on the OD side. Be sure you get the correct seals, they can be confused easily with others used in the trans. The ATSG tech manual covers the difference.



Install the center support in the case and be sure to line up the fluid passages on the valve body side. Install the center support bolts.
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  #26  
Old 03-20-2009, 04:01 AM
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Default Re: 200-4R Rebuild ... step by step!

Next the thick tapered snap ring with hooks goes in to hold the center support.



And the thrust washer with two tangs.

Now you can install the OD apply piston, return spring, and snap ring.




One easy mod to accomplish on the 200-4R is to add a friction clutch to the 4th clutch. The OD piston must be machine down .070" to do this as seen here:

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  #27  
Old 03-20-2009, 04:06 AM
jakeshoe jakeshoe is offline
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Default Re: 200-4R Rebuild ... step by step!

Then the retainer and snap ring. You can use a screwdriver to push down on the retainer and feed the snap ring in all the way around.
Once again be sure the thrust washer is in place, and install the OD ring gear.
Install the torrington bearing in the ring gear.




Now the already assembled OD and input shaft assembly can be installed. Set it in the ring gear and rotate until it seats.



Install a steel OD plate.


Then a friction.
On a stock trans there are only two frictions. So the stackup is steel goes in first, then a friction, then two steels back to back, then another friction, and last the backing plate and snap ring.
If you machined the apply piston, you can add a friction between the two back to back steels.
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  #28  
Old 03-20-2009, 04:09 AM
jakeshoe jakeshoe is offline
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Default Re: 200-4R Rebuild ... step by step!

You can air check the unit as you assemble.
You air check the low clutches at the feed passage shown:




You can aircheck the OD clutches by applying air to the left feed hole and center support bolt in this photo.



The hole directly right of that is the forward clutch pack, then the directs, then the furthest right passageway and center support bolt is the reverse feed passage. It is blocked on this unit for the dual feed mod to the direct clutches.
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  #29  
Old 03-20-2009, 04:13 AM
jakeshoe jakeshoe is offline
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Default Re: 200-4R Rebuild ... step by step!

The stock 200-4R has a weak 2nd apply due to a small servo apply area. The Buick Grand Nationals in 1986 and 1987 had the largest stock apply area and these servos are good to 400 HP but above that an aftermarket servo is necessary.
Shown here is a stock generic 200-4R servo, a GN servo, and a CKPerformance servo. The CKPerformance servo has the largest apply area of any servo on the market.
The Sonnax Super Servo is the 2nd largest, and the Superior/Fairbanks servo is 3rd.
Any of these will work well.


You must assemble the servo without the large cushion spring and seals and install into the case with the snap ring.



Be sure you have the band pin in the case to hold the band. You should be able to depress the servo cover .060" once this is done. This is how you set band clearance. If it is too tight and you cannot install the servo snap ring, you must grind the servo pin end down to get clearance. When you depress the servo cover, you should see the band tighten on the drum inside the trans. You can see this beside the VB area. If the clearance is too loose, you must get a longer servo pin or install a pin extender.

Once the servo has seals installed and is installed you can air check the servo here:


Be sure the band tightens around the drum.

Servo clearance is important. Too tight and you burn the band. Too loose and you can have a sloppy shift from 2nd to 3rd. The trans applies oil to 3rd gear, and this oil has to push the servo back into the cover away from the band. The longer the travel, the more oil is consumed by this cavity, and it slows the feed to the 3rd gear clutches
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  #30  
Old 10-08-2010, 11:08 PM
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Default Re: 200-4R Rebuild ... step by step!

This is a great thread, thanks for taking the time to post it.
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