Every 100K
I repack the front wheel bearings.
Change rear axle fluid.
Manual Trani Fluid change.
At 150-200 the Alternator Brushes may start to give you a problem. I changed mine at 150K before I had a Charging issue.

That's about it for the big Rollover. All the rest I consider regular upkeep and maintenance.
--
'75 Jeep CJ5 345Hp ChevyPwrd, two motorcycles, '85 Pickup: The '89 Volvo is the newest vehicle I own. it wasn't Volvos safety , it was Longevity that sold me http://home.lyse.net/brox/TonyPage4.html

I would replace the timing belt, as I normally do for the 50k service. While you're in there you can check the front oil seals and water pump.
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1986 Volvo 245

More than likely, you have probably replaced some of these parts such as ball joints and tie rods but they may need it again.

Check these out, but don't necessarily replace:

All bushings
Steering rack
Steering rack boots
Steering shaft u-joints
Inner and outer tie rods
Ball joints
Sway bar end links
Fuel sender (rust)
Engine mounts
Front engine seal leaks
Rear main okay?
Leaks from flame trap and/or oil separator
Tranny mount
Rear tranny seal and bushing (any leaks there?)
Cracks in tranny cooling lines - if slushbox
Struts and shocks
Fuel pressure regulator
Radiator
Radiator hoses
Master cylinder
Emergency brakes

I'm done. I'll let someone else add to this list....:)

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95 855 GLT Sportwagon, 93 854 GLT (for sale or parts car), 90 244 DL 300k :)