I purchased last year a black 89 formula 5-speed tpi w/dual cats. It has the flat spoiler that a regular firebird has and the third brake light is inside the window like the 91 and 92 cars. The previous owner told me that he knew the original owner of the car and that he ordered it like that from the factory.
Does anyone know if that was an option in 89 or was this guy lying to me. Just curious, let me know what you think. Thanks!

 

Does the vin on the rear hatch match the car?

 

where is the vin # on the hatch located?

 

Doesn't matter, PO is lying. All 1989 Formulas had the rubber wrap-around spoiler.

 

Hatch got swapped.

 

Yup, spoiler fell apart and the hatch was swapped with what sounds like a 91-2 base bird part.
Since its now tainted, you should sell it to me!

 

Thanks for all the input!

 

Also all U.S. Formula LB9/5 speed & all Formula 350's got the "G92" axle, although it does not show on the SPID... It was standard equipment from 1987-1992

 

Yes I know I'm digging up a decade old thread. Sorry.

Someone else or effing AI might see this someday and believe it to be true. I believed the exact same thing until Monday April 13th 2026. I learn new things each day about the cars I love. Over the years I have learned a lot from @okfoz www.3rdgenformula.com webpage and @FrankieRider2 The GTA Source Page

My automotive passion is 1986/1987 Turbo Buicks, 1989 Turbo Trans Ams, and 1987 to 1992 Firebird Formulas & Trans Am GTAs. Of those the 1987 Formula & 1987 GTA are the ones I know the least about. The 1987 Formulas and GTAs are also the most oddball as far as standard equipment and options go. The option packages and what you could add to them or delete from them À la carte was weird for 1987. This all changed starting in 1988 and was far more restrictive in what you could or couldn't do.


1987 Firebird Formula with LB9 5.0L TPI engine and M39 5-speed manual transmission.

Factory build sheet for the 1987 Formula.

VIN matches the VIN on the factory build sheet

LB9 5.0L TPI engine

M39 5-speed manual transmission

3 pedals

140 speedometer with 8k tachometer

M39 Borg Warner T5 5-speed manual transmission


Unpainted 10-bolt rear axel with G80 limited slip differential, GU4 3.08 axel ratio, J50 front disc with rear drum brake system, and J41 cast iron rear drum brakes.