77998 03K IN
2017-11-22
: Sonnax 77998-03K-In 77998-03K-IN 2520 instructions part uploads
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1. Disassembly
a. Remove OE piston and spring from 1-2 or 3-4 accumulator bore.
Discard piston, save spring for reuse.
NOTE: Some aftermarket shift kit springs do not t properly into Sonnax pistons.
In these cases, an OE spring must be sourced or Sonnax spring 74926 can be used.
b. Remove and discard OE pin.
c. For 1-2 location, plug pin bore by driving the appropriately-sized Sonnax
steel ball into it. Lightly stake bore after ball installation (Figure 1).
NOTE: OE pin diameter varies. Install ONLY the Sonnax steel ball that
corresponds to pin bore size. Discard unused steel ball.
d. For 3-4 location, no steel ball is necessary as this is a blind hole.
2. Installation & Assembly
a. Install Sonnax D-ring into groove at dome end.
b. Install Sonnax PTFE seal into groove at open-pocket end.
c. Continue installation as noted below:
‘94-Earlier
• 3-4 Piston: Install dome into case with spring in pocket.
• 1-2 Piston: Install dome into accumulator body followed by spring.
‘94-Later
• 3-4 Piston: Install dome into case. Some units do not have a spring
for 4th accumulator. If OE had a spring, install into piston pocket.
• 1-2 Piston: Install spring(s) into accumulator body, set piston pocket
opening onto spring, dome toward plate.
200-4R (All)
• 3-4 Piston: Install dome into case with spring in pocket.
• 1-2 Piston: N/A.
GM 200-4R, 4L60, 4L60-E, 4L65-E & 4L70-E
Case
3-4 Location
Pinless
Accumulator
Piston
D-Ring Seal
Steel Balls
(1-2 Location Only)
Pinless Accumulator
Piston Kit
Part No.
77998-03K
• Pinless Accumulator Piston
• D-Ring, Viton®
• Seal, PTFE
• Steel Ball (1) .312" dia.
• Steel Ball (1) .236" dia.
Patent No. 6,899,211
Viton® Rubber D-Ring
Dome
End
Open-
Pocket
End
1-2
Location
Drive OE pin out of cover. Plug pin bore by driving
the appropriately-sized Sonnax steel ball into it.
Lightly stake bore after ball installation.
Figure 1
PTFE
Seal
©2017 Sonnax Industries, Inc. 77998-03K-IN 10-23-17
800-843-2600 • 802-463-9722 • F: 802-463-4059 • www.sonnax.com
TRANSMISSION PARTS
Instructions
