Subtle exterior changes dominated 1978, as wheelbases and
dimensions were virtually identical to 1977. DeVille, Brougham, limo and Eldorado had
a bolder horizontal crosshatch grille. All but Eldorado had new rear bumper ends with
vertical taillamps and three-dimensional crest insignia, Most broughams, all California
Cadillacs and the fuel-injected DeVille sedan sported aluminum hoods. After the start
of production, Elk Grain vinyl tops would be used on all except Seville, which retained
a padded Tuxedo Grain vinyl top.
Passenger compartments had seven new interior colors and three new body cloths,
including Random velour. Of the 21 body colors, 17 were new and all but two of those
were exclusive to Cadillac. Signal-seeking AM/FM stereo radios were now standard on all
Cadillacs. For the first time, chromed wire wheels from the British firm of Dunlop were
offered as options on DeVille, Brougham, and Seville models. New electronic level
control (standard on all except DeVille) used a height sensor to signal a motor-driven
compressor that automatically adjusted for changing loads. The transmission had higher
downshift speeds this year. DeVille and Brougham body mounts were retuned for a
smoother, quieter ride. Four new special editions were offered:
- Seville Elegante
- Phaeton Coupe (or Sedan) DeVille
- revised Eldorado Custom Biarritz.
An available diesel V-8 engine (built by Oldsmobile) for Seville was announced during
the model year, at the Chicago Auto Show. So was a new electronic trip computer. All
Cadillacs except Seville carried a standard 425 cu. in. V-8. Cadillac hardly tried to
hide the boast that owning one had always "expressed success." As the full-line catalog
modestly proclaimed, "calling something 'the Cadillac of its field' is one of the finest
compliments you can pay a product."
For 1978, there were five models:
- DeVille (two-door coupe and four-door sedan)
- Fleetwood Brougham (four-door sedan)
- Fleetwood Limousine (four-door sedan, four-door formal limousine, and commercial chassis used in hearses and ambulances, etc.)
- Eldorado (two-door hardtop coupe)
- Seville (four-door sedan)
I. D. DATA
- Cadillac's 13-symbol Vehicle Identification Number (VIN) again was located on the forward edge of the windshield trim molding, visible through the windshield.
- Coding was similar to 1978.
- The model year code changed to "S" for 1978.
- Engine coding was now as follows:
- "B" V8-350 EFI
- "S" V8-425 4 Bbl.
- "T" V8-425 EFI
- "N" V8-350 diesel
|Engine||V8 350cc (5.7L)||V8 425cc (7.0L)||V8 350cc (5.7L) Diesel|
|Crankcase||4 qt||4 or 5 qt||6 qt|
|Crankcase with new filter||5 qt||5 or 6 qt||7 qt|
|AutomaticTransmission after draining||8 pt||8 or 10 pt||6 pt|
|Drive Axle||4.3 pt||4.3 or 4 pt||4.3 pt|
|Fuel tank||21 gal(US)||24 or 27.5 gal(US)||21 gal (US)|
|Cooling with heater||18.9 qt||19.8 or 24.3 qt||18.9 qt|
|Cooling with A/C||18.9 qt||19.8 or 24.3 qt||18.9 qt|
|Heavy duty Cooling||NA||NA||NA|
GASOLINE ENGINE TUNE-UP SPECS
|Engine V.I.N Code||B||S||T|
|Fuel delivery||EFI||4 bbl||EFI|
|Original Spark plug||R47SX||R45NSX||R45NSX|
|Gap||0.060 in.||0.060 in||0.060 in|
|Ignition timing (BTDC)||10° (8°)||18°@1400 rpm||18°@1400 rpm|
|Intake valve opens (BTDC)||22||21||21|
|Fuel pump pressure||5¼ to 6½ psi||5¼ to 6½ psi||39 min.|
|Idle speed||600 rpm||650 rpm||650 rpm|
ALTERNATOR AND REGULATOR SPECS
|Field current @ 12 V||4 - 4.5||4 - 4.5||4 - 4.5||4 - 4.5|
|Output||63 amps||80 amps||80 amps||145 amps|
|Regulator||Solid state||Solid state||Solid state||Solid state|
|Volts @ 75°||13.8 - 14.8||13.8 - 14.8||13.8 - 14.8||13.8 - 14.8|
BATTERY AND STARTER SPECS
|Engine||V8-350cc (5.7L)||V8-425cc (7.0L)||V8-350cc (5.7L) Diesel|
|Battery Ampere Hour Capacity||540 amps cold cranking power @ 0°F|
|Battery Terminal Grounded||Neg.||Neg.||Neg.|
|Starter, Lock Test, Amps||Not Recommended|
|Starter, Lock Test, Volts|
|Starter, Lock Test, Torque|
|Starter, No-Lead Test, Amps||65 - 95||65 - 95||40-140|
|Starter, No-Lead Test, Volts||9||9||9|
|Starter, No-Lead Test, RPM||7000 - 10500||7000 - 10500||8000 - 12000|
|Starter, Brush Spring Tension||35 oz. min.||35 oz. min.||35 oz. min.|
GENERAL ENGINE SPECS
|Main Brg Journal Dia.||2.4985 - 2.4995 (No. 1 2.4988 - 2.4998 in)||3.250||2.9993 - 3.0003|
|Main Brg Oil Clearance||0.0005 - 0.0021" (No. 5 0.0015 - 0.0031")||0.0001 - 0.0026||0.0005 - 0.0021" (No. 5: 0.0015 - 0.0031")|
|Shaft End-play||0.004 - 0.014||0.002 - 0.012||0.004 - 0.014|
|Thrust on No.||3||3||3|
CONNECTING ROD SPECS
|Journal Dia.||2.1238 - 2.1248||2.5000||2.1238 - 2.1248|
|Oil Clearance||0.0004 - 0.0033||0.0005 - 0.0028||0.0005 - 0.0026|
|Side Clearance||0.006 - 0.020||0.008 - 0.020||0.006 - 0.020|
PISTON AND RING SPECS
|Piston-Bore Clearance||0.0010 - 0.0020||0.0006 - 0.0014||0.0005 - 0.0006|
|Ring Side Clearance: Top Compression||0.0020 - 0.0040||0.0017 - 0.0040||0.005 - 0.007|
|Ring Side Clearance: Bottom Compression||0.0020 - 0.0040||0.0017 - 0.0040||0.0018 - 0.0038|
|Ring Side Clearance: Oil Control||0.0006 - 0.0098||None (side sealing)||0.0078 max.|
|Ring Gap: Top Compression||0.010 - 0.023||0.013 - 0.023||0.015 - 0.025|
|Ring Gap: Bottom Compression||0.010 - 0.023||0.013 - 0.023||0.015 - 0.025|
|Ring Gap: Oil Control||0.015 - 0.055||0.015 - 0.055||0.015 - 0.055|
|Seat Angle||31°(exh)||45°||intake: 45°; exhaust: 31°|
|Face Angle||30° (exh)||44° (exh)||intake: 44°;exhaust: 30°|
|Spring Test Pressure||187 lb @ 1.27 in.||160 lb @ 1.50 in.||[email protected]|
|Spring Installed Height||1-43/64" (1.671875")||115⁄16 in.||1-43/64"|
|Stem-to-Guide Clearance: Intake||0.0010 - 0.0027||0.0010 - 0.0027||0.0010 - 0.0027|
|Stem-to-Guide Clearance: Exhaust||0.0015 - 0.0032||0.0010 - 0.0027||0.0015 - 0.0032|
|Stem Diameter: Intake||0.3429||0.3416||0.3429|
|Stem Diameter: Exhaust||0.3424||0.3416||0.3424|
|Engine type||V8-350cc(5.7L)||V8-425cc(7.0L)||V8-350(5.7L) Diesel|
|Cyl. Head Bolts||130 ft.lb||90 ft. lb||130 ft. lb|
|Rod Brg Bolts||42 ft.lb||40 ft. lb||42 ft. lb|
|Main Brg Bolts||80 ft.lb (120 on # 5)||90 ft. lb||120 ft. lb|
|Crankshaft Damper or Pulley Bolt||310 ft.lb||Press fit||200 - 310 ft. lb|
|Flywheel to Crankshaft Bolts||60 ft.lb||75 ft. lb||60 ft. lb|
|Intake Manifold||40 ft.lb||30 ft. lb||40 ft. lb|
|Exhaust Manifold||25 ft.lb||22 ft. lb||25 ft. lb|
|Carb ID||17058230 (M4ME)||17058232 (M4ME)||17058233 (M4ME)||17058533 (M4ME)||17058532 (M4ME)||17058530 (M4ME)||17058531 (M4ME)||17058535 (M4ME)|
|Float Level||13/32 in||13/32 in||13/32 in||13/32 in||13/32 in||13/32 in||13/32 in||13/32 in|
|Air Valve Spring||1/2 turn||1/2 turn||1/2 turn||1/2 turn||1/2 turn||1/2 turn||1/2 turn||1/2 turn|
|Pump Rod||3/8 in||3/8 in||3/8 in||3/8 in||3/8 in||3/8 in||3/8 in||3/8 in|
|Primary Vacuum Break||0.150 in||0.140 in||0.140 in||0.140 in||0.140 in||0.140 in||0.140 in||0.140 in|
|Secondary Vacuum Break||0.165 in ||0.250 in||0.250 in||0.250 in||0.250 in||0.250 in||0.250 in||0.250 in|
|Choke Rod||0.080 in||0.080 in||0.080 in||0.080 in||0.080 in||0.080 in||0.080 in||0.080 in|
|Choke Unloader||0.230 in||0.230 in||0.230 in||0.230 in||0.230 in||0.230 in||0.230 in||0.230 in|
|Fast Idle Speed||1500 rpm||1400 rpm||1400 rpm||1400 rpm||1400 rpm||1400 rpm||1400 rpm||1400 rpm|
WHEEL ALIGNMENT SPECS
|Feature ||Eldorado ||Full size ||Seville|
|Caster Range ||1°N - 1°P ||2°P - 4°P ||1°P - 3°P|
|Caster Pref. ||0° ||3°P ||2°P|
|Camber LH wheel Range ||¾°N - ¾°P ||¼°N - 1¼°P ||¾°N - ¾°P|
|Camber LH wheel Pref. ||0° ||½° ||0°|
|Camber RH wheel Range ||¾°N - ¾°P ||¼°N - 1¼°P ||¾°N - ¾°P|
|Camber RH wheel Pref. ||0° ||½° ||0°|
|Toe-In ||0" ||0" ||1/16"|
|Steering Axis Inclination||6° ||10-19/32° ||10-5/8°|
1978 Cadillac Notes
- Introduced: September 29, 1977.
- Edward C. Kennard was general manager
- Robert J. Templin was chief engineer
- Wayne Kady was chief designer (Cadillac Studio)
- F. T. Hopkins was general sales manager until March
- L. B. Pryor became general sales manager in March
- Model year production (U.S.): 349,684 for a 3.9 percent share of the industry total and the second
highest Cadillac total ever.
- Calendar year production (U.S.): 350,761.
- Calendar year sales by U.S. dealers: 350,813 for a 3.8 percent market share.
- Model year sales by U.S. dealers: 347,221.
- Record sales greeted Cadillac for the third year in a row.
- The model year total beat 1977's mark by 6 percent.
- The new Seville diesel (engine built by Oldsmobile) sold only about 2,800 copies, barely half the early prediction.
- But it was introduced late in the model year.
- Sevilles in general hit a new production high.
- Eldorado did well also, as buyers snapped up the last of the vast Eldos before the 1979 downsizing.
- A three-month shutdown of the Linden, New Jersey plant, to tool up for the new E-body 1979 Eldorado, Toronado and Riviera models, contributed to a loss in calendar year production of DeVilles this year.
- Cadillac asserted that the company "consistently leads all U.S. luxury car makes in repeat ownership. Once you own a Cadillac," they suggested, "it is difficult to accept anything less."
- Cadillac production figures
Sedan de Ville88,951 (decreased 6,470)
Coupe de Ville117,750 (decreased 21,000)
Eldorado46,816 (decreased 528)
Seville56,985 (increased 11,925)
Series 6036,800 (increased 8,800)
Series 752,382 (decreased 1,531)