Leaded fuel Vs. Unleaded

gasoline

#1

I just bought an immaculate 1984 Class C Motorhome. It has 350 Chevy engine with only 18,000 Miles on it. Is it safe to use unleaded gas in this engine? Since it was manufactured during the leaded gas era.


#2

As far as I remember unleaded gas was required by 1975. My dad’s 75 Pinto was the first year of unleaded gas and catalytic converters. I’m not sure when it applied to trucks though.

Ed B.


#3
I don't think you could buy leaded gas in 1984.  It is a non-issue with that car.

#4

Leaded fuel was still available on the US market until January 1 1996 as off road use only. It could still be purchased at the pump in 1986 2 years after this motorhome was built.


#5

Engines don’t care about lead or no lead. That’s urban legend stuff. Your new prize will run FINE on unleaded and LOT Of IT!


#6

You should be OK as cast iron heads had hardened valve seats when lead free gas became available in the early mid 1970s. You can Google valve seat recession to read more, however. Some older engines originally designed for leaded gasoline can suffer valve seat recession when unleaded gasoline is used.


#7

That engine is ok for unleaded. Especially if it is 8.5 to 1 compression or less. If it has the small hole for unleaded, then it has never had the other kind.


#8

Engines don’t care about lead or no lead. That’s urban legend stuff. Your new prize will run FINE on unleaded and LOT Of IT!

Engines don’t care…but if you have a catalytic converter…it CARES a LOT. Using leaded gas with a catalytic convert will DESTROY the cat is very short order.

Unleaded gas has been around since the 70’s, but trucks were exempt from being required to use it until the early to mid 80’s. If this vehicle has a cat then you CANNOT use leaded gas.


#9

I forgot this line…

ANY car can run on Unleaded as long as it has the Hardened valve seats.