Hey guys! I am looking to possibly picking up a 91 420SEL for almost no money, the car is in great condition. The only thing that bugs me is how slow it is and the way the transmission does not shift smoothly (not horrible, but not the way i would like it to) The car has 200,000 miles and the engine is extremely strong. Body is solid, no rust etc. Brakes are solid, new tires, excellent interior.

I have driven it and it seems that once the transmission warms up it starts to get smooth!

Is there any simple fix to this like swapping trans fluids or something? I also heard something about there being vacuum components that also have to do with the trans.

All help is appreciated as I am an Audi guy and this is very new territory for me!!


Cheers,


Stefan

 

The W126 transmission is known sometimes to be abrupt when shifting cold or staying in lower gears slightly longer than when it's warm, to get it to operating temp faster. The shiftsshouldnt be crude though. That box is picky about the tranny fluid sometimes. You can try another brand, making sure it's the proper kind, or you can never go wrong with the actual MBZ tranny fluid that came with the car when it left factory. From there, vacc adjustments can be made for shifting characteristics of more of your liking but be for warned, make sure who ever is tinkering with the adjustments know exactly what he/she is doing or you'll find your self with more shifting problems than you know what to do with.

The W126 is a good car. The US version 420SEL is by no means fast compared to newer German type cars but it's no slouch considering the weight it's pulling and the tech from early 80s it's using to do it. i.e no fancy varible valves and cpu per cylinder or all that nonsense. Which makes it easier to fix. The Euro version of the 420SEL had lot better responsive and performance. Oh righ one last thing the W126 seems slow off the line because tey start in second gear. There is first gear start up kits out there that add a little more pep in the step feel to the car. If that still dont satisfy your mild speed demon than throw a 5.6 under there. If that dont work, you can always hunt down the holy grail 6.0 AMG engine. If that still dont work, hell, you need a Ferrari.

 

Thank you very much for your in depth response. It did put my mind to ease. The vehicle was doing exactly what you said within the first 10 minutes that I was driving it. It seemed like it was staying in the initial gear a lot longer and not switching over.

I am picking the car up tomorrow so I am bouncing off the walls right now. lol..


Even though I am a hard core Audi guy at heart, I have always wanted one of these bad boys. I remember being young and seeing the mafia convoys on the roads in eastern europe. good times!

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