1986 Mercedes-Benz S-Class SEL 420
Summary:
One word: MAGNIFICENT!!!
Faults:
The timing chain let go at 148,000 miles causing major engine failure. I had no idea this could happen. Up to this point the engine was perfect!
General Comments:
This is the most incredible Mercedes I have ever owned. I highly recommend it, if you can still find one in good condition. That is the reason I replaced the engine after the problem rather than replacing the car!!!
Would you buy another car from this manufacturer? Yes
Review Date: 15th May, 2008
2nd Apr 2009, 21:04
Yup, it seems like you got a good deal. I can't find a single one here in California for under about $3000 USD. And the $3000 ones need work.
BTW, diesels in general shift sort of hard under hard acceleration. They don't tend to generate a lot of vacuum which controls the shifting. Check to make sure that all vacuum hoses are connected properly under the car.
Also there is a 'vacuum modulator' under the car next to the transmission pan (this also controls the firmness of shifting). I wouldn't suggest you mess with this unless you are confident in your mechanical skills. You will never be able to make it shift completely smooth, you can only adjust shift points (when it shifts) and slightly how hard it shifts.
ALSO, if you haven't already done so, have your transmission fluid, filter and gasket replaced. Don't do a flush because a clogged filter can also cause hard shifting and eventually lead to a bad transmission. So yeah it was common, but you can dial it in a little bit better. Good luck.