Ford C-6 Full Manual Reverse Valve Body - BTE 621000
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Ford C-6 Full Manual Reverse Valve Body - BTE 621000

Ford C-6 Full Manual Reverse Valve Body

Shift Pattern: PRN123

BTE 621000 Kit Contains:
QTY   DESCRIPTION
One(1)   Full Manual Valve Body
One(1)   1/8 x 27 Pipe Plug
One(1)   Intermediate Servo Gasket
NOTE: This kit is not intended for installation in a transmission in poor general condition. It will not correct a malfunctioning or slipping transmission.

Before you begin installation allow transmission to cool to avoid burns from hot fluid or parts. Select a well lighted work area and it is very important to keep all parts clean. Use a box or pan to keep transmission parts from getting misplaced. Wash parts thoroughly with a good solvent.

STEP 1 Drain oil pan. You will need a pan to catch fluid. Remove transmission oil pan bolts. When removing bolts, remove so pan will not drop completely off but will be held in place so that one side will allow the fluid to be drained. After the fluid has drained, remove the rest of the bolts and pour out the remaining fluid. Dispose of the fluid in an environmentally responsible manner. Remove gasket and discard. If gasket material sticks to transmission pan or case, remove all material completely. Transmission does not have a drain plug.

NOTE: Some vehicles will require removal of the crossmember to remove the pan. Be sure you support the back of the transmission so you don't damage any linkage or engine parts.

STEP 2 Remove transmission pan.

STEP 3 Remove existing valve body by locating and removing eight (8) 3/8" hex head bolts. Remove valve body by pulling straight down.


STEP 4 Carefully remove the oil filter by removing the nine (9) 5/16" socket bolts. Pull the filter straight down. Inspect the oil filter. Replace the filter if it is dirty or has not been changed in over 25,000 miles.

STEP 5 Disassemble transmission as necessary to remove detent spring. Late model transmission cases have this detent spring which is located under the inside shift linkage. (SEE PHOTO 1) Remove the flat detent spring by removing the 1/4" hex head bolt. Your new BTE Full Manual Valve Body has the detent inside the valve body.

STEP 6 Reinstall transmission components into transmission.

STEP 7 Install BTE Full Manual Valve Body. Use only six (6) hex head bolts. Do not use filter bolts until you are ready to reinstall filter. Torque bolts to 10 foot pounds. Make sure that the manual control valve is properly aligned to the inside shift linkage. Manually operate the shift lever to make sure rod is in shifter valve.

STEP 8 Reinstall transmission gasket and pan. NOTE: If you are not using a stock shallow pan, check clearance between pan and filter. You must use a car filter and not a truck filter when using a stock pan. Torque pan bolts to 12-15 foot pounds.

STEP 9 No Servo modifications are needed when using a Rubber Servo. We recommnd using the BTE "R" Ratio Servo Piston Kit, BTE 66528R (Not Included).

STEP 10 Reinstall intermediate servo.

STEP 11 Reinstall all linkage and fittings. You must reinstall modulator.

STEP 12 Front Band Adjustment: Using a 13/16" wrench, loosen outer jam nut. Tighten the band adjusting screw to 120 inch pounds. Next, back off adjusting 1-1/2" turns. Hold the band adjusting screw in place and tighten jam nut securely.

STEP 13 Shifter Adjustment: Make sure detent locations on transmission matches shifter selector in vehicle. Place transmission and shifter in Drive to make adjustments. Loosen pinch bolt located on shift rod and align shifter and transmission in Drive and tighten bolts. Shift into all gears.

STEP 14 Fill transmission with 4-5 quarts of Automatic Transmission Fluid before starting engine. BTE recommends our BTE Transmission Fluid, BTE 940600, which is formulated for high performance use. After the engine and transmission has warmed up check fluid level in your transmission. Add additional fluid if needed. Fluid line should be even with "Full" mark on transmission dipstick. DO NOT OVERFILL TRANSMISSION.


STEP 15 Test Shifting: Take all precautions necessary to secure and support your vehicle. The rear wheels must be off the ground to test. Place shifter in neutral, start engine and check fluid level. Add fluid until it is at the "add" mark. Shift transmission through all gear positions. Do this about 10 times. Recheck fluid level. DO NOT OVERFILL TRANSMISSION. If the transmission shifts properly you are ready to road test.

STEP 16 Road Test: To allow the the vehicle to warm up, drive 1 to 2 miles then recheck fluid level. Add fluid if necessary to reach "Full" mark on dipstick. DO NOT OVERFILL TRANSMISSION.

BTE 66528R

"R" Ratio Servo Piston Kit

BTE 66528R Kit Contains:
QTY   DESCRIPTION
One(1)   Billet Servo
One(1)   Servo Pin
One(1)   Billet Cover
Two(2)   Springs

Designed to improve shift quality and shift tuning. Fits 1968 and later cases.



Posted by Brandon Barrentine at 6:57 PM