1978 Cadillac Fleetwood Brougham
8-cyl. 425cid/180hp 4bbl
With an experienced team and a lot of data.
Protect your 1978 Cadillac Fleetwood from the unexpected.
The OPEC fuel crisis is the reason for this generation of Cadillac’s existence. GM was simply forced to bring the bulk and excessive mass of its largest cars down to something not seen since the early 1950s. The all-new 1977 Fleetwood Brougham was lighter, shorter and narrower.
For 1977, the big-block Cadillac V-8 engine was reduced in both bore and stroke, resulting in 425 cubic inches instead of the prior 500, but with a power reduction of only 10 hp to 180 total. The new cars were vastly better in every way, with interior and trunk room being broadly similar to the prior cars. This was partly due to the new car having a thinner door and more intelligent design overall, allowing for plenty of stretch-out room inside for six corn-fed Americans. The trunk could still hold several golf bags or plenty of luggage as the situation required. Fuel consumption was reduced as well.
Sales went up year-over-year from 24,500 to 28,000, so the new “fleeter” Fleetwood Brougham had gained immediate public acceptance.
As was expected, the standard equipment list for the cars was extensive, and the option list nearly as long. The d’Elegance option added special pillow contoured seats in velour with matching interior trim on door panels, special wheel covers and also special pinstripes.
The 1978 cars were changed little, as were 1979 cars. Halfway through the 1979 model year, the Oldsmobile-supplied 350 cid diesel V-8 engine was made an option on the Fleetwood Brougham. 1980 brought the addition of a two-door Fleetwood Brougham and a bore reduction for the Cadillac V-8 engine to 368 cid. This resulted in a 150 hp rating, with the fuel injection version limited to the Eldorado and Seville lines. Maximum torque was inevitably reduced as well: 265 lb-ft compared to 320 lb-ft at 2000 for the larger 425 engine of 1977-79.
The 1981 cars brought an aide to fuel efficiency with the addition of electrical mechanisms to shut off valves to either two or four of the cylinders when under light load. This was made standard equipment across the board, except on the Seville that had the Oldsmobile diesel V-8 engine standard that year. Cadillac hailed the technical advance, but the electronics did not prove to be reliable in the field. A Buick-produced 252 cid V-6 engine was a “delete option” on the Fleetwood Broughams. This was the first non-V-8 Fleetwood for many decades, and the Oldsmobile diesel continued to be optional at extra cost.
With the reliability issues of the V-8, Cadillac executives decided to push ahead and rush the adoption of a previously planned, very small, aluminum-block V-8 engine. It debuted for 1982, coupled with a lightweight overdrive automatic transmission. This was the HT-4100. It was fuel injected and rated at 125 horsepower, but only managed 200 lb-ft of torque. The extremely light weight of the engine did help to reduce the weight of the Fleetwood by 244 pounds, but in reality there wasn’t much in the way of performance. The Buick V-6 and Oldsmobile diesel V-8 remained available to buyers who selected them.
By 1983, the HT-4100 was uprated to 135hp, but Cadillac’s rush to begin production of the new high-tech engine began to manifest itself in reliability issues for customers. Oddly enough, the reliable Buick V-6 engine did not return to the option list. 1984 Fleetwood Brougham cars were largely unchanged from 1983, but for 1985, with the introduction of a new smaller “Fleetwood” on a front-drive platform, buyers voted with their wallets and continued to buy size and bulk, with over 14,000 more Fleetwood Broughams sold year-on-year with either the Cadillac 4.1 V-8 or optional 5.7 Diesel V-8.
For 1986, the rear-drive Fleetwood Brougham sedan carried on in high style. The Fleetwood Brougham gained a slightly more powerful 307 cid V-8 engine of 140hp and 255 lb-ft of torque, which brought back something resembling spirited acceleration to these big cars. This was the final year of the Cadillac Fleetwood Brougham, which was replaced by a car simply called the Cadillac Brougham for 1987.