Guys,

what type anti freeze should i use in my 87 v6?

green... ethylene glycol. Zerex still makes it.

See cave, coolant fill
Ethylene Glycol or Propylene Glycol is fine.
Do Not use 50/50 mix unless you are using to top off system with coolant that sure mix it right...
Do Not mix Ethylene Glycol and Propylene Glycol. See cave, same article.

------------------
Dr. Ian Malcolm: Yeah, but your scientists were so preoccupied with whether or not they could, they didn't stop to think if they should.
(Jurassic Park)

The Ogre's Fiero Cave (It's also at the top and bottom of every forum page...)

Recommended Fiero fluids:

GM TSB:

quote Propylene Glycol Engine Coolant Bulletin No.: 43-62-01B Date: April, 1995 Subject: Propylene Glycol Engine Coolant Models: 1994 and Prior Passenger Cars and Trucks This bulletin is being revised to reflect most current information on propylene glycol engine coolant. Please discard Corporate Bulletin Number 4362O1A (Group Reference 6 - Engine). General Motors has been reviewing data supplied on the performance of propylene glycol engine coolant in GM vehicles. It is our conclusion that propylene glycol engine coolant will perform adequately under most vehicle operating conditions. As a result, propylene glycol engine coolant (meeting performance specification GM 1825M) may be used in GM vehicles and will not affect the warranty coverage. Prior to adding propylene glycol engine coolant to the cooling system, all the existing (ethylene glycol) coolant must be removed. This can be accomplished either by utilizing water-based coolant flushing equipment or "waterless quick change" equipment available in the GMDE program. As with any coolant change procedure, be sure to thoroughly purge the heater core and block as well as the radiator before attempting to convert the system to propylene glycol coolant. Freeze/Boil point levels are different for propylene glycol than for ethylene glycol engine coolant. To accurately determine freeze/boil protection level, it is imperative that coolants not be mixed. Removing all the used coolant as previously discussed resolves this concern. Freeze protection of propylene glycol cannot be determined using a standard hydrometer. Rather, a refractometer or test strip must be used. Propylene glycol engine coolants may be recycled in the same manner as conventional ethylene glycol coolant. No adverse effects will be encountered if these coolants are mixed prior to recycling, however, the ratio of propylene glycol coolant to ethylene glycol coolant should be kept low to minimize the effects on freeze point measurements.

In short... GM said OK to use either but Don't mix EG and PG coolants. Any aftermarket brand coolant should be fine.

But Note... Don't use "long life" EG that some car makers uses. GM Dexcool has lawsuit(s).

------------------
Dr. Ian Malcolm: Yeah, but your scientists were so preoccupied with whether or not they could, they didn't stop to think if they should.
(Jurassic Park)

The Ogre's Fiero Cave (It's also at the top and bottom of every forum page...)