With an experienced team and a lot of data.
Protect your 1978 Mercedes-Benz 450SEL from the unexpected.
The Mercedes-Benz 450 SE and SEL sedans replaced the 300SE 4.5 V8, which was the last of the 1960s “tall” grille Mercedes sedans. The changes were largely to meet the stricter U.S. safety requirements, and the big bumpers necessitated a redesign of the body. The engine also powered the new 450SL roadster.
The 450SE sedans were widely considered one of the best cars for the money in their day, with a 190-hp fuel-injected, 4.5-liter SOHC V8, three-speed automatic transmission, independent suspension and disc brakes all round, and standard air conditioning. The SEL model stretched the wheelbase four inches for back seat passengers.
The Mercedes-Benz 450 received Bosch K-Jetronic fuel injection in 1975, but there were few changes until 1977, when the base SE model was dropped. Also in 1977, the 6.9-liter 450SEL was introduced with 250 horsepower, and a 140-mph-plus top speed. This model was only built through 1979 but it was considered the best sedan extant during its day, and it cost a whopping $15,000 more than the “ordinary” $30,000 450SEL. The 6.9 could do 0-60mph in 7 seconds, which was pretty good going for a car that weighed about 4,500 pounds, and it rode on a complex but sublime hydro-pneumatic self-leveling suspension.
For anyone considering buying one of these models, a pre-purchase inspection is essential. Complete service records and an unbroken chain of ownership are a must, as original owners could afford, and always maintained the cars. Later aspirational owners, on the other hand, tended to sell the cars on when they received bad news from the garage. A total of 101,179 450SE and SEL sedans were sold and there are plenty of survivors.
The same is true in spades with the 6.9-liter cars, but with only 7,380 built, these have always been collectible and far fewer have fallen into serious disrepair. Of course, some have so be forewarned.