Just purchased perhaps the best car I've ever owned 1984 300d and am looking for suggestions on engine maintenance and then some. I posted on the engine thread because it is my primary concern. Let me give some information (some info not about engine) about what I've done before suggestions are offered.

Car has 125k miles and a near perfect interior (I'm bragging)
Valves are done
New Injector lines
New ball joints upper/low and inner/outer wheel bearings
Purged the system
Transmission flush and replaced differential oil
Cleaned the ADAL banjo bolt on the turbo intake
New filters for everything that has a filter other than P/Steering
New transmission linkage bushings
Removed muffler etc.
Removed EGR valve.
New pads and turned rotors

Issues - Ticking from motor (back passenger side) sometimes, but not always. (maybe mounts?) sometimes while the engine is cold and sometimes at hot

Transmission - cannot make up it's mind about being gentle or a little peppy (in terms of kick from shifting)

Vibration on steering wheel over 72 mph and sometimes at 45 to 50 mph. Not bad though. I figure its the bad wheel shocks.

Need -
oil pan gasket
Sooner than later oil cooler hoses (no real leaking)
motor mounts
engine shocks
shocks (recommendations please. Bilstein, medium or hard?)

What else is should i be looking for on maintenance or checking on for the motor?

Motor starts with no problem above 40 degrees and glow plug light never is on for more than 5 seconds except below 40 degrees.

Burns no oil.

Running temp is around 90 more or less if hot or cold out

Oil pressure is never below 2 bar.

I am also looking for performance mods. I've checked this forum and seen what can be done but am looking for a verdict on what should be done versus something that might help in power.

I want to stick with the stock turbo for now.

Can I get taller gears for my differential so I can cruise at lower rpms on the highway?

I'm looking to go manual in the future, don't know if 4 or 5 speed at this point.

All advice and suggestions for maintenance and performance are welcome.

Nice Car. New front tires and an alignment will rid the vibration at high speeds. I have the same ticking problem with my om603, cant figure out what it is.

(01-15-2010 08:51 AM)TotalDiesel Wrote:  Nice Car. New front tires and an alignment will rid the vibration at high speeds. I have the same ticking problem with my om603, cant figure out what it is.

Glad I am not alone on the ticking. I did replace the tires and had them balanced and that made some difference. However, I was too cheap for the alignment I wish I had done. I'll just do it some time this week and see how things turn out.

85 300D and 300SD used the 2:88 differential, you have the 3:07.
the speedo is geared to the Diff. The 300D speedo will not fit/work as it is operated by a mechanical cable.

the 300SD is electricaly driven.

There is also the 2:47 Differential in some of the W126 gassers. 81 to 85 Diff will work. 86 to 91 refered to as second generation 126 have a different diff sub frame mounting points. will not work in first Gen.

If you go with the 2:47, the diff flange will have to swapped over from the smaller flange the SD uses. different size flex diesk`s.

Charlie

Be sure to get the spedo from the donor car with the Diff.