"new" car glitches

[Mark Alan Selleck <glassimpressions@xxxxxxxxxxxx>]

Just got back from a 2100-mile "shake-down" trip with my "new" '85 535i: NC
to PA to LI to Rochester,NY, to Akron, OH, back home.  Trip was pretty
uneventful, and I'm pleased with the car.  Mileage is a little less than
with our recently totaled 533i, and the clutch is noticeably stiffer, but
it's a pleasure to drive.  Purchased with 143,00 miles, now has almost
147,000.  A couple of things I could use some help with:

Half-way through the trip, the "check brake lights" warning started coming
on when I engaged the cruise control.  Every time, now.  Suggestions?

I'm wanting to put Mobil 1 in the car(used about 1 quart of oil since
purchasing the car, running mostly high-speed interstate).  I've heard
various cautions about changing over a high-mileage car, some suggestions
that upon first change over oil should be dumped after 1000 miles.  Opinions?

Thanks in advance for any help.

Mark Selleck

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