Considering a 1997 S420, 1-owner with 61,000 miles. She has had all service provided by the same dealer I use for our 2 SLK's. The service book is up to date. Never had a W140 -- had several W 123's but nothing of this level of pure luxury...

What should I specifically look for past the obvious?

thanks for any advice and assistance...Marc

 

Cannot believe there are no opinions out there! Cautions? Experiences?

 

A few things, talking as an owner of a 1997 S500.

1) Wing mirrors, fold them in, check the wires are ok, Merc were still using bio-degradable wire insulation on the wing mirrors in 1997 and the insualtion just falls off and the mirror will need replacing. Usually happens after about 10 years, so around now! About £300 each, fitted.

2) Oil leaks, I bet there is probably some oil leaking from the head somewhere, but as long as its just a tiny tiny bit, then its ok.

3) Stearing box - heavy car, starts to leak after a while, but again as long as its minor its ok.

The garage I take mine to be serviced at said almost ever W140 by the time it has done 100k will have problems 2 and 3, its normal and ok as long as minor.

4) Air Con - gas has lubrication in it, so the worst thing is to not use it at all during winter. Put it to cold, and check it blows out ice cold air, it it does not, I would question why the garage has not picked it up/charged the gas, as it is a B service check I think (I would quesion if there is anything else they have not picked up too if that were the case). If the aircon has a leak it will be around £1500 for a new compressor etc, so very expensive.

5) Electrics - check everything works fine inlcuding c.control, look out for the red led on the interir rear view mirror flashing, when you go along as this is an indecator of something not right somewhere.

6) Gearbox - should not have probs till at least 150-160k miles for most people if looked after. Get up to 70mph and check engine RPMs are around 2200-2500. Changing should be very very smoth. When you first start the car and the engine is cold, there is an upshift delay, which stops the gearbox from upshifting until the engine is at 35 deg cent and the cat converter is up to temp (a tokan environmental effort) so it may sound like it is spinning fast, but it is normal! They may be a jerkey change at 3000rpm if the upshift delay is still going at that is the change threshold early on. When operating normally the changing of the gears should be very very smooth, for me this in the summer is usually after about 2 mins. Also its a great 5 speed gearbox and it tries to get to the highest gears asap in my experience.

7) Stearing, should be very light, you can stear a w140 with your little finger, it is power stearing at the extreem level!

8) Get one with parktronic! Trust me, it will be worth it!

9) Drive the car around, turn the aircon off, and engine should sit at 80degrees cent, if it doesn't I would start to ask questions (in traffice it may go from 80 to 85 but then back down to 80). Dont think mine has ever gone over 90!

10) Check tires, a new set is £500 at Kwik Fit, or £950+ vat at a merc dealer for the same tires using a Kwik Fit subcontractor - so the same thing!

11) Don't expect a service to be much less than £600 to £1000, and the service interval is 10k miles.

12) Check where the boot closes and the boot lid catch goes into the car body, a rust hot spot.

13) Check for general rust around the car, especially around weel arches.

14) Sounds like the car has done around 5000 miles a year, which is low, what sort of driving, if lots of very short distances it should really have been serviced (or at least had the oil changed) every 5000 miles, given possible low usage, check the aircon works! It is possible the car has only had 5 or 6 services - if so that is low for 12 years and expect a lot of things potentially need looking at soon (bearings, starter motor etc), but you might be lucky.

15) Wiper blades - check they are ok, new set is £70gbp.

16) Is the dealer any good, is it a merc dealer if so they have probably never done any preventative servicing which is key with a W140! First thing I would do is take it to a well known independent and get it checked over and have the rubber seals around the gearbox where the wires go in changed asap so the wiring loom is not destroyed, a merc garage will never do this, as they want to charge you £2,000 for a new loom round the gearbox. Really look at that service booklet and check everything has been done. It is quite common for major steps to be missed out by garages!

It it were me doing it, as soon as I got the car, I would have it serviced, check front suspension, will prob need adjusting, as a heavy car and designed to be adjusted over time, have engine oil changed, cooling system flushed, breakfluid changed, and gearbox oil changed, but I think gearbox oil change is not meant to be done until either 50k or 100k, think its 100k though so maybe not that step. And most importantly for any S-Class owner, really clean and condition the leather and polish the outside!

Hope this helps. Overall they are great cars, and very reliable if looked after and preventative servicing takes place. Alas not too many garages these days are good at doing the last bit. Mercedes arn't, thats for sure!