I have a '77 Pontiac Astre Formula Safari (kammback) Station Wagon, Iron Duke, T50 5 speed, posi, silver, black coarse cloth with black vinyl stripes interior like new, amazingly, body has lower edges rust... ... bought it long ago to get the tranny for my '75 MG Midget... along with Buick 215 V8... started driving Astre and took a liking to it... got amazing MPG for 1970's... one day looked in manual and saw why: 28 MPG City and 34 MPG Hiway... in '76, bought new '77 Grand Prix with 301 V8 that also brought good MPG back: 16 City/23 Hiway... considering SBC for the Astre, either 350 from '87 GTA or 550 HP SBC 405" I'm building... also have '85 Fiero 2M4, 5 speed, white, grey interior... health problems in 1999 and other times slowed those projects way down... I'm in NW Ohio... Astre has a sticker from Cheever Pontiac/Cadillac in Hillsdale, Michigan... have a buddy was living in Apts. in Belleville, Michigan and Condo in Ft. Myers, Florida... he suffered health problems, condo building damage, vehicle damage from the recent Hurricane... giving up the Michigan apt... I expect to be in VA hospital in Ann Arbor Tuesday... I see some of you are in that neck of the woods... never seen a picture of an Astre Formula Wagon before today... none online or in brochures... just some production numbers so figured it was real... there used to be an old TV show that always started with a family in a silver Sunbird wagon...

Heres part of one.https://uploads.tapatalk-cdn.com/202...a9aa341b56.jpg

Sent from my Moto Z3 Play using Tapatalk

I started reading this discussion then realised that much of it is thirteen years old!
ha-ha!

giving this a bump for continued "Formula" discussion. ;)

Yeah, I hope most of the previous commenters are still alive and active...

I would love to see some pictures of your wagon, I have never seen one in person. I still have my stalled Yellow Formula project, the body and paint and even the decals are on it, but it still lacks the drive train install & interior. Hope to get back at it after I finish the 67 Spring FB this year (Hopefully)

Didn't know if GM ever started building a heavy duty all synchro 3 speed to replace the all synchro heavy duty 3 speeds they were buying from Ford for use in GM products?

The HD 'Dearborn' transmission was replaced by a HD 3 spd Muncie in the A / G bodies in 1970. Continued in the B body for '70, but was no longer available in 71.
GM continued using the Dearborn in the square-body GMC/Chevy pickups through the seventies.

Ever hear any reason why the Muncie 3 speed was just a one year transmission?
Was it all synchros, including 1st gear?
Was Muncie 4 speed replaced by Borg-Warner 4 speeds then, as well?

The fully synchronized HD Muncie was used through '73 for the Pontiac A body. 70-71 for the Firebird and Grand Prix
First introduced in the 69 Chevelle / Camaro

I need to make a small correction;
the Muncie three speed was a Chevy only deal for the 1969 model year;
Keep in mind this was at a time when divisions got to have exclusive use of new products that were developed by (or through?) them.

The Muncie three speed was the base transmission in all 1969-SS models (afaik).

For 1970 the Chevrolet division exclusivity was gone, and in a move I don’t quite understand, the Muncie three speed was nla behind any Super Sport model;
It was used in some non-SS vehicles that required a HD three speed.
The trucks continued to use the Muncie three speed through to 1974.

As already mentioned the 1970 GM A-bodies all now used the Muncie three speed - except for the Chevelle Super Sport;
This continued through to 1973 or 1974 - I am a little unclear when the transmission stopped being offered for use in the A-bodies.

The Firebird had the Muncie three speed fir 1970 & 1971, and it has been suggested that it was dropped for 1972 because of how few were ordered.

As far as I know, the 70/71 Camaro never used the Muncie three speed.