Tool Required VB-FIX Required
- Burnt bands
- Burnt clutches
- Delayed engagement
- Low line pressure
AODE/4R70W units frequently have loose or worn manual valves which allow critical line pressure to cross leak into adjacent hydraulic circuits or to the exhaust.
This Sonnax manual valve restores proper clutch/band clamping forces and actuation timing by eliminating critical line pressure leaks between the manual valve and valve body. Additionally, the design of this manual valve eliminates valve rotation caused by pressurized fluid acting on the valve while flowing through the valve body.
Oversized Manual Valve Kit
- Retaining Ring
Many AODE, 4R70W and 4R75W units have a loose manual valve or worn bore that creates a significant line pressure leak. Loss of line pressure results in delayed engagements, burnt clutches and bands. OE manual valves have been observed continuously rotating in the bore due to forces caused by the flow of fluid. Constant rotation of the valve contributes to premature wear of the valve bore. The Sonnax tool kit F-76948-TL46 oversizes the bore to accept the Sonnax oversized manual valve kit 76948-46. This manual valve eliminates the constant axial rotation and its precision machining tightly controls clearances to minimize line pressure leaks.
- Eliminates line pressure losses to cross leaks
- Establishes tight clearances between manual valve spools and bore lands
- Ends flow-induced axial rotation of manual valve
Fits 92-later units. Upgrades 92-98 valve bodies to 99-later specifications. The 99-later units have a quicker direct clutch exhaust on 4-2 manual downshift.
You need this if...
Wiggle testing the OE manual valve shows .0025" or greater play between valve and bore. Use a dial indicator and place the manual valve in the drive position when performing the wiggle test (Figure 1).
Click here to view PDF if instructions do not appear below.
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