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Dead Parrot · 12-17-2018, 07:58 PM

My 75 with dual tanks has the 2 port senders, and no canister and no return lines. The vents are a short hose with a plastic covered vent like you use to vent the differential.

Mine was HD emission from the factory. No cats, only had PCV and THERMAC for emission controls.

There was a lot of variation in square emission setups due to rapidly changing rules, weight rating on truck, state of sale, phase of moon, etc. That is why you are finding so many variations.

12-17-2018, 07:58 PM	#6
Dead Parrot Registered User Join Date: Aug 2012 Location: Oklahoma City, OK Posts: 2,496	Re: Dual Tank Venting My 75 with dual tanks has the 2 port senders, and no canister and no return lines. The vents are a short hose with a plastic covered vent like you use to vent the differential. Mine was HD emission from the factory. No cats, only had PCV and THERMAC for emission controls. There was a lot of variation in square emission setups due to rapidly changing rules, weight rating on truck, state of sale, phase of moon, etc. That is why you are finding so many variations.