It has about 86k miles and since last summer it has been parked in the garage for 4-5 years. The car is in the great condition and I never had any problems with the engine.
if it does not smoke your fine.like they said leaving a car sit without starting it and charging battery and letting oit get to temp is the worst thing IMO.but people do it all the time.I guess it how you prep it first
Today I was under the car and saw this, oil spots are only on the left side, right side is perfectly dry.
My car is in garage every day and everything is dry on floor.
Obviously slightly leaking while the car is running.
rear main seal most likely, i'd replace the oil pan gasket while your at it.
Easier said than done. At a minimum you have to lift the engine to get enough clearance and even then it's a difficult proposition. If the pan gasket is fine just leave it. And before I jumped to the conclusion it's the rear main I would confirm that it's not leaking from the back of the lower intake or valve covers towards the rear of the engine. These can often be overlooked with the erroneous assumption that it's the rear main leaking just because you see oil dripping from the flywheel cover.
What is the optional consumption of oil for 95GT?
My car consumes 1L per 500-600 miles, is that ok?
No, that's too much. Ideally you shouldn't need to top up the oil in between service intervals.
Eagle hit the nail on the head about the seals drying up when the car is parked for a long time. In your case, it would be easy to replace the valve stem oil seals 'cause that's most likely to be where you're losing oil from the crankcase.
Easier said than done. At a minimum you have to lift the engine to get enough clearance and even then it's a difficult proposition. If the pan gasket is fine just leave it. And before I jumped to the conclusion it's the rear main I would confirm that it's not leaking from the back of the lower intake or valve covers towards the rear of the engine. These can often be overlooked with the erroneous assumption that it's the rear main leaking just because you see oil dripping from the flywheel cover.
thats why i did my rear main while swaping k members. some of us plan out such things.......
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94 gt aode baumannator,pi stallion 3000 stall,transgo,mega bite jrs,3.90 gears,31 spine moser axles,comp exteme,1.7 roller rockers,190 pump,mac cold air,ford 1 5/8 unequals, off road h,flowmaster 2 chamber with stainless tails,msd box,PIH(a9p computer ajustable fan controler),q1a k-member,kenny brown frame ties,driveshaft loop,air pump eliminator kit,bbk 70mm tb,pro-m bullit meter,24#injecters,ported heads&intake,and all the little bolt ons.
1995 Mustang GT Consumption of oil 
