LH side is the engine oil cooler. RH side is the transmission.
If it's a coolant leak and not oil from that cooler pipe fitting the radiator is knackered.
Those are called Jiffy Tite fittings. They have an o-ring inside that eventually gets flat and weeps.
Replacement fittings come with new o-rings and brandy new strange bendy spring clips.
I don't re-use the fittings or bendy spring clips if they rusty or are of unknown age or more than a few years old.
Lisle sells a four piece set of release tools for these. They're darn nice to have.
This is how the fitting works.
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1959 M35A2 LDT465-1D SOLD
1967 Dodge W200 B383, NP420/NP201 SOLD
1969 Dodge Polara 500 B383, A833 SOLD
1972 Ford F250 FE390, NP435/NP205 SOLD
1976 Chevy K20, 6.5L, NV4500/NP208 SOLD
1986 M1008 CUCV SOLD
2000 GMC C2500, TD6.5L, NV4500
2005 Chevy Silverado LS 2500HD 6.0L 4L80E/NP263
2009 Impala SS LS4 V8
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