MN12 Differences Between the Years

Rick_Leuce

Registered User
Hi all,

I was just doing some research on the subtle changes that happened between the different model years of MN12 Thunderbirds. For instance, according to one of my sources, the automatic high-beam dimmer was an option in 1990 but discontinued in 1991.


One difference I was trying to figure out was the year in which the Thunderbirds switched from 19 Gallon fuel tanks to 18 gallon fuel tanks. I've found a few sources that confirm the 1990 Thunderbirds used a 19 gallon fuel tank. However, I've found conflicting information regarding the 1991 Thunderbird, some saying 19 gallon and others saying 18 gallon fuel tank. I was curious if anyone knew exactly what year the fuel tanks switched from 19 to 18 gallons.

Thanks :)
 
18 or 19..? ~~~, i can only fill my 94' up to 15.xx gallons so id have a max 16 gallon tank..most i ever got in was almost 16 and i was wayyy on E and wayyy over topped it off..
 
Well, the '89 (automatics?) had a boost cut-out in reverse.

My '90 Anny/auto has brake pedal ignition lockout.

Did all years offer optional front cornering lights?

What year did lighted trunk reflectors begin?

When did the wheel style change?

Early SC's had the hatchet style console park brake lever.

Moonroof switches and map lights differed.

VMM changed.

Traction control went to electric/ABS type.

Windshield washer tank was relocated.

Later gloveboxes came with lid dampers and center console lids came with cup-holders. Trunk release moved to center console from glovebox. What was first year fuel door went from finger pull to button/solenoid? When did auto-lock doors come into effect? Which years offered JBL Premium sound system?

Auto climate began in '91 or 92?

Engine changes included uprated superchargers, windage tray etc. Different exhaust with the gas tank change? Speaking of which I've never squeezed more than 17 gals. into my Anny., but I've never run it out of fuel, either.

Has to be a long list, I think...
 
Cornering lamps were discontinued after 93. However the lines for the cutouts are still molded into 94-95 bumper covers on the inside.

Lighted trunk panels began in 92

Wheel style changed in 93 for both SC and LX.

Windshield washer tank moved in 93.

Brakes and spindles changed in 93.

I think Auto Dimming Brights were available on 89 models and maybe 90 also.

M5R2 gear ratios changed in 94.

And Chrome accents on the dash and silver buttons on the radio/climate disappeared after 90 or 91.

Stainless trim on the door panels was gone after 91.
 
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Another change was 91 (or 92 maybe) had the all black interior options with the black (instead of grey) gauge bezel.
 
93 was the last year for Black interior

Metal Hub caps were phased out in 92 I think.

I normally only get 14.XX gals in, normally fill up with 1/8 to 1/16
 
Well, the '89 (automatics?) had a boost cut-out in reverse.

My '90 Anny/auto has brake pedal ignition lockout.

Did all years offer optional front cornering lights?

What year did lighted trunk reflectors begin?

Moonroof switches and map lights differed.

VMM changed.

Traction control went to electric/ABS type.

Windshield washer tank was relocated.

What was first year fuel door went from finger pull to button/solenoid? When did auto-lock doors come into effect? Which years offered JBL Premium sound system?

Auto climate began in '91 or 92?

Has to be a long list, I think...

I have a 1991. So I can confirm that the Automatic Climate Control option was first available in 1991. I also believe that the ECM in my 1991 is like what is in the 1992 and 1993 Thunderbird SCs. I was warned that my spare 1990 ECM may not work with my 1991. I can always tell a 1991 from a 1989 and 1990 based on the passenger-side dash (1989-1990 has some coin storage cubby thing on top of the dash) but the 1991 passenger-side of the dash is smooth.

My 1990 and 1991 have the ignition thing where there is that extra "lock" position in the ignition where you have to push a button to turn the ignition one more click before you can release the key.

My 1990 and 1991 are a pull-finger fuel door. I think I saw a 1992 or 1993 LX with a fuel door that didn't have a finger-open spot (probably the button-open kind)

The lighted reflectors started for the 1992 model year. 1989-1991 Thunderbirds have part of the reflectors go over the license plate (about the size of fingers) but the ones that light up don't have "fingers" that go over the license plate.

My 1991 I know has the JBL sound system, sadly the previous owner messed with the speakers in my 1990 so I don't know for sure there.

I know that 1992-1993 Thunderbirds are basically exactly the same. Except that when I look up pictures on Google (someone please confirm this) I don't see any 1993 Thunderbirds with cornering lamps in the front bumper, but I do find images of 1992 Thunderbirds with cornering lamps in the front bumper. Because its an option, there just might not be very many that have it. I do know that cornering lamps in the front bumper were offered from 1989-1991 and I'm sure for 1992. I'd be surprised if 1993 did not offer them (because it's the same front bumper). Again, someone please confirm this. :)

I've even been keeping track of map lights and moon roof switches (because I'm officially weird). I parted out a 1990 SC with a moonroof and it had different lights and switches than my 1991 with a moonroof. IT WAS SO COOL, the map lights were NOT in the celling, they were actually in the rear-view mirror (I took it cuzz I had to). My 1991 has the moon roof switch in between two smaller switches that control the map lights (in front of my head). My 1990 (no moon roof) has a single hub thing in the middle of the ceiling (behind my head) that has two switches for the two lights inside. Maybe I should take pictures and save them in a spreadsheet :D

I wished I took a picture of the 1990 with a moonroof before I gouged out its switch, cut the end of the wire, and broke a small area of the windshield because the bead wouldn't come off.
 
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Twitchy Mirror!

My 1990 has this weird "twitchy mirror thingy." I like it, if someone has their headlight on behind me, my rear-view mirror has a sensor and motor in it that makes it turn up and down slightly (I guess so that it doesn't shine in your eyes). But my 1991 has something different, I'm guessing. My 1991 has a 89 DSO and pretty much every option Ford offered except the front license plate bracket and its not an automatic; two options I'd rather not have anyways :D

I think the 1991 rear view mirrors like auto-tint or something. It has a sensor, but no motor.
 
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My 1990 has this weird "twitchy mirror thingy." I like it, if someone has their headlight on behind me, my rear-view mirror has a sensor and motor in it that makes it turn up and down slightly (I guess so that it doesn't shine in your eyes). But my 1991 has something different, I'm guessing. My 1991 has a 89 DSO and pretty much every option Ford offered except the front license plate bracket and its not an automatic; two options I'd rather not have anyways :D

I think the 1991 rear view mirrors like auto-tint or something. It has a sensor, but no motor.

That is sort of a fun option. My old 1989 (base model, but high options) had that. You could get it along with the autodim headlamps (boy, that was a heavy mirror assembly), but you could not get it with the sunroof (because the overhead lights took up the space that the mirror motor needed).
 
Well, the '89 (automatics?) had a boost cut-out in reverse.

My '90 Anny/auto has brake pedal ignition lockout.

Did all years offer optional front cornering lights?

What year did lighted trunk reflectors begin?

When did the wheel style change?

Early SC's had the hatchet style console park brake lever.

Moonroof switches and map lights differed.

VMM changed.

Traction control went to electric/ABS type.

Windshield washer tank was relocated.

Later gloveboxes came with lid dampers and center console lids came with cup-holders. Trunk release moved to center console from glovebox. What was first year fuel door went from finger pull to button/solenoid? When did auto-lock doors come into effect? Which years offered JBL Premium sound system?

Auto climate began in '91 or 92?

Engine changes included uprated superchargers, windage tray etc. Different exhaust with the gas tank change? Speaking of which I've never squeezed more than 17 gals. into my Anny., but I've never run it out of fuel, either.

Has to be a long list, I think...

WHAT BOOST CUT OUT IN REVERSE??!!!! thats no fun
 
WHAT BOOST CUT OUT IN REVERSE??!!!! thats no fun

Boost cut out in reverse? What is that? Does it mean that the supercharger is like temporarily disabled or is there like some sort of governor that prevents the engine from revving high? :confused:

By the way, I collected a bunch of Ford Thunderbird dealership flyers (one for each year of Thunderbird) I'll try studying them to see if they may shed any light on this weird Crusade I'm on.
 
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89-93 the coolant overflow is on passengers side and the radiator mounting tabs changed in 94 and i think they went to a copper core radiator for 93-94...
 
Boost cut out in reverse? What is that? Does it mean that the supercharger is like temporarily disabled or is there like some sort of governor that prevents the engine from revving high?


Bypass solenoid circuit only on ’89 SC’s (auto trans?) to prevent boosting when in reverse. Works in addition to the vacuum pull that opens the bypass valve at the supercharger.

EEC code: 82 O Supercharger By-pass Solenoid circuit failure (3.8L SC only)
 
Bypass solenoid circuit only on ’89 SC’s (auto trans?) to prevent boosting when in reverse. Works in addition to the vacuum pull that opens the bypass valve at the supercharger.

EEC code: 82 O Supercharger By-pass Solenoid circuit failure (3.8L SC only)

That's really interesting. I don't know if it is a common issue on Super coupes with manuals, but I have to rev between 1,500 and 2,000 RPM and not let the clutch out all the way if I want to go in reverse without the car stalling. If I let the clutch out all the way, I either have to go in reverse at like 5 MPH (which can be scary backing up in a crowded parking lot) or else the car stalls; so I just let the clutch out most of the way. I almost feel like driving in reverse is like taking off in second gear. My 1991 isn't as dramatic to back up, but it has an automatic differential in it (with lower gears), so I rarely ever stalled it going in reverse and I can let the clutch out all the way when backing down a driveway.

Whenever I go to a parking lot in my 1990, I always pull through so that my front is facing out in the aisle and I don't have to use reverse :cool:
 
Cornering lamps were discontinued after 93. However the lines for the cutouts are still molded into 94-95 bumper covers on the inside.
Windshield washer tank moved in 93.

Brakes and spindles changed in 93.

Front brake rotors and hubs also changed in 1991... The 1989-1990 rotors have a different size center hole, and the hub had a different size lip for it. If you get 1991 hubs and rotors, they swap for the earlier type.

And Chrome accents on the dash and silver buttons on the radio/climate disappeared after 90 or 91.

The 1989 had the chrome buttons on the HVAC and radio. They were black for 1990.

Stainless trim on the door panels was gone after 91.

Too bad; it's a nice touch!
 
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I've even been keeping track of map lights and moon roof switches (because I'm officially weird). I parted out a 1990 SC with a moonroof and it had different lights and switches than my 1991 with a moonroof. IT WAS SO COOL, the map lights were NOT in the celling, they were actually in the rear-view mirror (I took it cuzz I had to). My 1991 has the moon roof switch in between two smaller switches that control the map lights (in front of my head). My 1990 (no moon roof) has a single hub thing in the middle of the ceiling (behind my head) that has two switches for the two lights inside. Maybe I should take pictures and save them in a spreadsheet :D

I wished I took a picture of the 1990 with a moonroof before I gouged out its switch, cut the end of the wire, and broke a small area of the windshield because the bead wouldn't come off.

The cover panel for the moonroof changed at some point between 1990 and 1993. My 1990 has plastic vents through the cover so you can get a breeze and still be protected from the sun. They removed those and went to a solid panel by 1993 (not sure quite when).

Cost-cutting, sigh. :(
 
The cover panel for the moonroof changed at some point between 1990 and 1993. My 1990 has plastic vents through the cover so you can get a breeze and still be protected from the sun. They removed those and went to a solid panel by 1993 (not sure quite when).

Cost-cutting, sigh. :(

My 92 doesn't have the vents.
 
With regards to the fuel tank question, 92 was the changeover year. 89-91s had a 91 gallon tank, and 92-97s had the 18 gallon tank. The difference in the tanks was to make a more direct exhaust path rather than having the exhaust have to go all the way to the outside edge of the car and then back to the center. Also with regards to the fuel door, I know I had an 89 XR7 that had the remote fuel door, and the spot for the button is there on all 89-93 cars, so it was definitely available prior to 91. I don't know if it was a Cougar only option for the first 2 years though. Other differences I can think of are
-Only 89s had silver climate control buttons, switched to black for 90-93
-Window and door lock switch bezels had a visible screw holding them in at the top for 89/90, and a clip for 91-93
-93 tbirds had the interior color matched steering wheel and center console whereas 89-92s were black regardless of interior color, then for 94 the bird went back to black and the Cougar got the color matched wheel and surround
-The rear disc brake rotors were thicker on 89-92 than on 93+, and the rear calipers are different to accommodate that difference
-97s had a completely different shape cluster than 89-96s
-Digital cluster was offered from 89-93. For 89-92s, the digital speedo would "peg" at 85mph, however in kph it would go as high as 199. 93s digital clusters however will keep reading all the way up to 199mph
 
Also with regards to the fuel door, I know I had an 89 XR7 that had the remote fuel door, and the spot for the button is there on all 89-93 cars, so it was definitely available prior to 91.

Agreed - I actually retrofitted the flat door, remote button and solenoid into my '90 Anny. All the wiring was already there and all I had to do was remove the knockouts and install the related components.

Speaking of speedos, the change from 120 to 140 was in '94?

As for the cornering lamps, I lost one of the exterior bezels in a car wash, and had to buy two to get one with the right depth...otherwise they looked identical.

Don't forget the hoods and the wiper cowls.

And auto seatbelts in early years (non-canada?).
 
Yes, because the 5.0L started that year, and it fit better up front for that engine, so they moved it for both.


5.0 Started in 91. Sport 5.0 was only available in 91 and 92 and came with SC brakes and front bumper cover with fog lights (The reason SC stopped getting molded into the bumper after 90). They dropped the sport model for 93 unfortunately. That's when Ford started to cheap out a bit and only offered LX and SC. I have a 93 5.0 and I don't think the washer reservoir was moved for space reasons, because there is a big empty hole on the drivers side fender apron where the washer reservoir would be on older models. I think the reasoning was 93 was supposed to be the first year for the late model 94/95 style. It was delayed for some reason. The washer/coolant reservoir was relocated to make room for the new larger 94/95 high current fuse/relay box and the ignition stuff on the drivers side apron. 93 has a lot off odd body stuff like that. The cowl is the same as late model, the top of the passenger fender apron has the square punch outs for retaining the 94/95 engine harness that runs over the inner fender instead of next to the manifold. The spindles, brakes, and Teves, is the same as 94/95. Clutch and brake pedals are 93 specific. I'm sure there's other weird 93 stuff I'm forgetting.
20150405_1338441.jpg
 
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