The 350 became the 450 in 1973 gaining power windows and some other interior refinements but still retained the same appearance. 1974 ushered in the era of tightening emissions and the dreaded DOT regulations which resulted in the 5 mph bumpers, thermal reactors and lower engine power output. The car continued in this form through 1976. For 1977 the poorly designed thermal reactors were replaced with a conventional catalytic converter and the car began the last 4 years of its life with increased refinement and reliability. Sales were up significantly in 1977-1979 with prosperity in the United States driving the increase. The final year of the 450SL was 1980 and the changes were subtle confined to minor refinements and a loss of power. The need for fuel efficiency and Mercedes' desire to begin the change to aluminum engines throughout the range gave rise to the 380SL introduced in the US in 1981. With only 155 hp the 380's were not particularly quick but were quite refined being very quiet and smooth. The car continued through 1985 largely unchanged with the exception of ABS brakes and drivers side airbag becoming available in 1984.

Mercedes' philosophy swung back toward performance with the introduction of the 560SL in 1986. The ultimate development of the 107 chassis, the 560SL had it all, power, handling and refinement. The most noticeable outward change was the change to the handsome 15" flat alloy wheels combined with a deep air dam under the nose. Further refinement included burl wood inside and contoured seats. We feel the 560SL represents the most value for the money at current prices. The pricing of the 107 chassis followed a dizzying climb from roughly $11,000 in 1972 to $68,000 in 1989!

Technical:
While the cars from this era of SL certainly were quite durable they did suffer from various problems. The engines can accumulate enormous mileage given proper maintenance and with careful attention to the timing chain health. A chain or chain guide problem is the usual culprit that kills these motors. And the condition exists in any V-8 from 1971-1989; hence we inspect the chain/tensioners/guides on every V-8 that arrives regardless of year or obvious chain noise. In most cases we find unacceptable chain slack and/or fractured plastic guides and replace these items as necessary. Neglecting the chain can have disastrous results, the usual calamity being a broken guide being dragged up the chain and wedging between the cam gear prompting chain slippage or breakage. This will allow pistons to contact valve heads with noisy and expensive results. This condition was exacerbated when the factory, in an effort to lighten the valve train, reduced timing chain width by about half with the introduction of the 380SL. This simply moved the time of failure up by tens of thousands of miles and cost the factory a fortune replacing chains/engines under warranty. Realizing their mistake, Mercedes phased the double width timing chain back into the cars mid 1983.
The expansion of this section is underway and will appear soon!