Common problems
Mercedes Diesel Glow Plugs and Glow Relay: Cold Start Fixes
A healthy OM616 or OM617 diesel should start on a cold morning with a wait light, a bit of a grind, and…
Guide hub
Maintenance guides
Service intervals, fluids and capacities, plugs, battery, tires and DIY jobs.
All guides
Common problems
Mercedes W126 Climate Control Problems: Diagnosis and Fixes
Automatic climate control on a W126 can keep a large cabin evenly comfortable, or it can become the most expensive personality on…
Maintenance
Mercedes OM617 / W123 Timing Chain: Interval, Symptoms and Cost
The OM617 five-cylinder diesel — and its four-cylinder OM616 cousin in the 240D — turns the camshaft with a roller timing chain,…
Common problems
Mercedes W123 Vacuum Door Locks: Diagram, Diagnosis and Fix
Central locking on a W123 is a vacuum system, not an electric actuator in each door the way a modern car works.…
Maintenance
R107 Jack Points and How to Lift It Safely
Where to safely jack and support an R107, how to use the factory jack points without damage, and where to put jack stands.
Maintenance
R107 Alignment Specs and Finding a Shop
R107 wheel alignment explained: what toe, camber and caster settings mean, what to ask the shop, and why the car pulls or wanders.
Maintenance
R107 Lowering Springs and Ride Height
Can you lower an R107? Options for spring pads, shorter springs and euro-style ride height, plus what it does to ride, alignment and value.
Maintenance
R107 Front Wheel Bearings: Check, Adjust and Repack
How to check, adjust and repack R107 front wheel bearings, what a bad bearing sounds like, and how rear bearing problems differ.
Maintenance
R107 Ball Joints and Front End Rebuild
How to check R107 ball joints, control arm bushings and tie rods, what wears first, and what a full front-end rebuild involves.
Maintenance
R107 Idler Arm Bushings: Symptoms and Replacement
What the R107's idler arm does, how worn bushings show up, how to inspect them and how to replace them.