4L60 Re-Rebuild for my C20

[Irish_Alley]

that sucks

[LTZ C20]

that sucks

Tell me about it.

[bd]

Sorry to hear that.  Most of us have been there at one time or another.  Before tearing it down, confirm your suspicion by pressurizing the cooling system with the spark plugs removed and cranking the engine to see which cylinder(s) pump coolant.  You can also remove the headers and inspect the exhaust ports with the cooling system pressurized.  In addition, perform a compression test and/or cylinder leak-down test.  Collect as much diagnostic data as you can while it's still together.

[LTZ C20]

I plan on doing a block test to see if there are exhaust gases in the cooling system and I'm going to use my boroscope to look inside the cylinders with spark plugs out and crank if over with the plugs out too. I know for sure it's the passenger side. Zero smoke from left exhaust, I have dual exhaust with no crossover so each side is independent of the other.

[VileZambonie]

Unless you baked it, don't waste your time, just pull the heads.

[LTZ C20]

Unless you baked it, don't waste your time, just pull the heads.

Already done.