The OE springs in many Jatco transmissions wear or become fatigued, causing low baseline pressure. OE replacements are hard to find, and many aftermarket springs have unacceptably high spring rates. The Sonnax elevated pressure main pressure regulator springs are intended to provide a minimal baseline pressure increase (approximately 10 psi over OE baseline pressure), enough of an increase to help restore full line pressure. The springs may be used to replace worn OE springs and also to correct low line pressure caused by worn transmissions.

Highest quality spring material.
Designed to slightly exceed OEM spring rates.
Manufactured to tight tolerances.
Drop-in installation requires no modification.

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