Amsoil site shows regular Automatic trans fluid, but if it was mine I would use a synthetic. Around that time Ford was specing Mercon. So a Mercon V fluid should work because it's back speced.
Manual Transmission,T5 5-SPD......MA
Synthetic Multi-Vehicle Automatic Transmission Fluid(ATFQT)
Torque-Drive Synthetic Transmission Fluid (ATD1G)
Here is the full deal on it.
1988 FORD THUNDERBIRD 2.3L 4-cyl Engine Code [T] Turbo
LUBRICANTS & FLUIDS:
Engine Oil
Grade 1......API*
Maximum Performance Signature Series 100% Synthetic 0W-30 Motor Oil (AZOQT) Signature Series 100% Synthetic 0W-30 Motor Oil (AZOQT)
Drain Interval Information
Maximum Performance SAE 5W-30 Synthetic Motor Oil (ASLQT) SAE 5W-30 Synthetic Motor Oil (ASLQT)
Drain Interval Information
Performance Plus XL 5W-30 Synthetic Motor Oil (XLFQT) XL 5W-30 Synthetic Motor Oil (XLFQT)
Drain Interval Information
Performance Synthetic 5W30 OE Motor Oil (OEFQT) Synthetic 5W30 OE Motor Oil (OEFQT)
Drain Interval Information
All TEMPS......5W-30
Manual Transmission,T5 5-SPD......MA
Synthetic Multi-Vehicle Automatic Transmission Fluid (ATFQT)
Torque-Drive Synthetic Transmission Fluid (ATD1G)
Automatic Transmission,A4LD......MA5 [1]
Synthetic Multi-Vehicle Automatic Transmission Fluid (ATFQT)
Limited Slip Differential, Rear......GL-5*
All TEMPS......90 [2]
SEVERE GEAR 75W-90 Synthetic EP Lubricant (SVGQT)
75W-90 Synthetic Long Life Gear Lube (FGRQT)
SEVERE GEAR 75W-110 Synthetic EP Lubricant (SVTQT)
SAE 80W-90 Synthetic Gear Lube (AGLQT)
Standard Differential, Rear......GL-5
All TEMPS......90
SEVERE GEAR 75W-90 Synthetic EP Lubricant (SVGQT)
75W-90 Synthetic Long Life Gear Lube (FGRQT)
SEVERE GEAR 75W-110 Synthetic EP Lubricant (SVTQT)
SAE 80W-90 Synthetic Gear Lube (AGLQT)
Fluids
Power Steering Fluid......FA
Synthetic Supershift Racing Transmission Fluid SAE 10W (ARTQT)
Brake Fluid......HB
AMSOIL Brake Fluid DOT-3 (BF3SN)
Clutch Fluid......
[1] This specification has been updated from Mercon to Mercon V
per a Technical Service Bulletin from the manufacturer.
[2] Identification: see upper left differential tag, code
on plate at driver's door.
FILTERS:
Oil Filter 25,000-Mile Ea Oil Filter (EAO15)
Oil Filter WIX 51515 Oil Filter
Air Filter Absolute Efficiency Air Filter (EAA129)
Air Filter WIX 46128 Air Filter
Fuel Filter WIX 33097 Fuel Filter [1]
Transmission Filter WIX 58939 Auto Tran Filter
Oil Vapor Filter WIX 46978 Air Filter
[1] The filter comes with two clips, but if shorter clips are needed, get WCK11 clips locally.
NGK PLUGS AND WIRESETS:
No Recommendations
WIPER BLADES:
Blade Class Driver Passenger
ExactFit T182 T182
NeoForm T16180 T16180
Winter T37180 T37180
CHASSIS LUBRICATION:
0-2 Fittings, 0-2 Plugs..........LL
CAPACITIES:
Engine, with filter..........4.6 quarts [1]
Automatic Transmission, A4LD Initial Fill..........3 quarts
Automatic Transmission, Total Fill
4 speed A4LD..........10.1 quarts
Manual Transmission, T5 5-SPD..........5.5 pints
Differential, With 8.8 ring gea Rear..........3.9 pints
Differential, With 7.5 ring gea Rear..........3.2 pints
[1] After refill check oil level.