Hi Bob,
As GVZ mentioned, the service manuals are available free online from MB, or you can buy them on CD-ROM from the dealer, or some people have posted the CD contents online with a nifty HTML navigation (
like this) instead of MB's funky Flash navigation/menu. The manuals are available in hardcopy form via eBay (except the M119 engine manual, which was never available in print from MB), but the hardcopies are not cheap.
For diagnostics, the main item you'll need is a blink-code reader. You can build one, or buy one from eBay (
click here). The code reader will come with a code list, throw it in the trash immediately, and use
this code list instead. If you can stomach the cost,
this adapter makes the code reading much easier (note that you'd need to buy/build a reader with 4mm pins if you're using this adapter). Or just shell out ~$600 for the Chinese SDS for use with your laptop... this will give you access to live data from the computers, along with reading codes. If you get the SDS, you don't really need the blink code reader, but it wouldn't hurt to keep the blinker box in the trunk or something (along with the code list), for emergency use.
Special tools - this depends on what particular job you are doing. One I'd recommend is the Koken compact Allen driver (
click here), not cheap, but it will save you a lot of misery when removing the valve covers. Another is the
M119 spark plug socket. There are lots more but I wouldn't worry about it until you need to do a certain job; i.e. if you replace timing chain guide rails, there are a few tools you'd want to buy... but if a previous owner already had this done, there's no need to buy the tools. If you intend to do any suspension work, look for a Klann spring compressor (I've got one for sale in the classifieds at the moment).
Best place to buy OE dealer tools & parts is parts.com (lowest prices anywhere). I generally use AutoHausAZ or ElAutoParts for most of my aftermarket parts. Aftermarket tools come from a variety of sources, mostly whomever has the right tool at the right price.
Please post some info & photos on your new car, btw! Maybe start a new thread in the "Owner" forum?
