Pagoda SL Group

W113 Pagoda SL Group => General Discussion => Topic started by: Jeff Collins on June 11, 2006, 11:35:22

Title: Torq converter/fluid dampner
Post by: Jeff Collins on June 11, 2006, 11:35:22
What is the story on these componets,some trans have torq converters some have the dampner,are they interchangable,is one better than the other?

68 250 sl auto/ac
86 944 Porsche
96 K35 t/d 4w
99 ultramax
2000 fatboy pro
Title: Re: Torq converter/fluid dampner
Post by: Klaus on June 12, 2006, 10:01:00
Jeff,
historically, the torque converter, by increasing the torque on startup allowed fewer gears, but it had slippage which resulted in a loss in fuel economy of about 5% versus a manual transmission. Mercedes had their first application of 3-speed automatic transmissions with torque converter in the 50s in the 300 series, but that transmission was purchased from Borg-Warner.
When Mercedes decided to build their own transmission, due to the emphasis on fuel economy they chose a design with fluid dampener (hydraulic clutch) and 4 gears (although startup usually was in second). These had less slippage and the fuel economy penalty was less than 2% in comparison to a manual transmission.
With the later introduction of the lock-up torque converter, this difference in fuel economy penalty was minimized, and the next generation of MB automatic transmission also had a torque converter.
You cannot put a torque converter on an old hydraulic clutch automatic transmission; they were not designed for the torque peaks.

Klaus
1969 280 SL
Title: Re: Torq converter/fluid dampner
Post by: Jeff Collins on June 15, 2006, 05:09:07
Thanks Klaus,my understanding of this is a whole lot better now.

68 250 sl auto/ac
86 944 Porsche
96 K35 t/d 4w
99 ultramax
2000 fatboy pro