Tapered threads of OE fittings crack case when overtightened.
The Sonnax adapter allows the case to be salvaged without removal.
A common complaint in late-model Chrysler rear-wheel-drive units is a cracked and/or leaking case caused by installing the cooler lines. The tapered threads and the lack of a stop on the OE cooler line fitting can load the case and create a fracture, resulting in leakage that may require replacing the case. The Sonnax adapter seals on the leading edge, preventing fluid from reaching the fitting threads and crack. The fitting has straight, not tapered threads to prevent the crack from spreading.