Can you put Sae 10w-40 high mileage in my Gmc jimmy s15 4.3 period it has 305 thousand miles

Most older cars use 10w-30. 5w-30 wouldn't hurt.
The most important thing is to change the oil and filter on a regular basis. 200-300k miles is not too much to expect with regular oil changes.
You could do synthetic and maybe see a small amount of mpg increase and a definite decrease in engine wear. Sometimes synthetic will leak more til it swells the seals.
With synthetic you can up the miles traveled between changes.
7500 is what I do.
There are also high-mileage oils out there.
The Fram XG series is a really good oil filter.

Engine oil capacity with oil filter replacement = 6.0 litres.

Oil grade for 2001 Audi A4 Quattro 2.8
1. SAE 5W-30 / 5W-40, VW 502.00 - all temperatures.
2. SAE 10W-30 / 10W-40, VW 502.00 - all temperatures.
3. SAE 5W-50, VW 501.01 - all temperatures.
4. SAE 10W-50 / 10W-60, VW 501.01 - all temperatures.
5. SAE 5W-30 / 5W-40, VW 501.01 - bellow +15 Celsius degrees.
6. SAE 10W-30 / 10W-40, VW 501.01 - bellow +15 Celsius degrees.
7. SAE 15W-40 / 15W-50, VW 501.01 - above -15 Celsius degrees.
8. SAE 20W-40 / 20W-50, VW 501.01 - above -15 Celsius degrees.

LONGLIFE engine oil:
1. SAE 5W-30, VW 504.00 - all temperatures.
2. SAE 0W-30, VW 503.00 - all temperatures.


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Depends on the season and temperature that it will be driven in.
Generally 10w-40 is for the summer, and the thinner 10w-30 is for the winter, if you so desire.

According to the chart, 5w-30 is preferred but 10w-30 can be used in 0 deg. F up to 100 deg. F and beyond.

Fuel and Engine Oil Recommendations GENERAL INFORMATION Oils The SAE (Society of Automotive Engineers) grade number indicates the viscosity of the engine oil; its resistance to flow at a given temperature. The lower the SAE grade number, the lighter the oil. For example, the mono-grade oils begin with SAE 5 weight, which is a thin, light oil, and continue in viscosity up to SAE 80 or 90 weight, which are heavy gear lubricants. These oils are also known as "straight weight'', meaning they are of a single viscosity, and do not vary with engine temperature. Fig. 1: Look for the API oil identification label when choosing your engine oil
Fig. 2: Before installing a new oil filter, coat the rubber gasket with clean oil
Multi-viscosity oils offer the important advantage of being adaptable to temperature extremes. These oils have designations such as 10W-40, 20W-50, etc. The "10W-40'' means that in winter (the "W'' in the designation) the oil acts like a thin 10 weight oil, allowing the engine to spin easily when cold and offering rapid lubrication. Once the engine has warmed up, however, the oil acts like a straight 40 weight, maintaining good lubrication and protection for the engine's internal components. A 20W-50 oil would therefore be slightly heavier than and not as ideal in cold weather as the 10W-40, but would offer better protection at higher rpm and temperatures because when warm it acts like a 50 weight oil. Whichever oil viscosity you choose when changing the oil, make sure you are anticipating the temperatures your engine will be operating in until the oil is changed again. Refer to the oil viscosity chart for oil recommendations according to temperature. The API (American Petroleum Institute) designation indicates the classification of engine oil used under certain given operating conditions. Only oils designated for use "Service SG'' or greater should be used. Oils of the SG type perform a variety of functions inside the engine in addition to the basic function as a lubricant. Through a balanced system of metallic detergents and polymeric dispersants, the oil prevents the formation of high and low temperature deposits and also keeps sludge and particles of dirt in suspension. Acids, particularly sulfuric acid, as well as other by-products of combustion, are neutralized. Both the SAE grade number and the API designation bottle be found on the oil can. For recommended oil viscosities, refer to the chart. Fig. 3: Viscosity chart
SYNTHETIC OIL There are many excellent synthetic oils currently available that can provide better gas mileage, longer service life, and in some cases better engine protection. These benefits do not come without a few hitches, however; the main one being the price of synthetic oils, which is three or four times the price per quart of conventional oil. Synthetic oil is not for every truck and every type of driving, so you should consider your engine's condition and your type of driving. Also, check your truck's warranty conditions regarding the use of synthetic oils. Both brand new engines and older, high mileage engines are often the wrong candidates for synthetic oil. A synthetic oil can be so slippery that they can prevent the proper break-in of new engines; most manufacturers recommend that you wait until the engine is properly broken in 3000 miles (4830 km) before using synthetic oil. Older engines with wear have a different problem with synthetics: they leak more oil as they age. Slippery synthetic oils get past worn parts easily. If your truck is leaking oil past old seals you'll most probably have a much greater leak problem with synthetics. Consider your type of driving. If most of your accumulated mileage is high speed, highway type driving, the more expensive synthetic oils may be a benefit. Extended highway driving gives the engine a chance to warm up, accumulating less acids in the oil and putting less stress on the engine over the long run. Trucks with synthetic oils may show increased fuel economy in highway driving, due to less internal friction. If synthetic oil is used, it should still be replaced at regular intervals as stated in the maintenance schedule. While the oil itself will last much longer than regular oil, pollutants such as soot, water and unburned fuel still accumulate within the oil. These are the damaging elements within a motor and must be drained regularly to prevent damage. Trucks used under harder circumstances, such as stop-and-go, city type driving, short trips, or extended idling, should be serviced more frequently. For the engines in these trucks, the much greater cost of synthetic or fuel-efficient oils may not be worth the investment. Internal wear increases much quicker on these trucks, causing greater oil consumption and leakage.

1986 CHRYSLER FIFTH AVENUE 5.2L 8-cyl Engine Code [P]

LUBRICANTS & FLUIDS:
Engine Oil Grade 1....SAE ..API*
Above -18C......10W-30, 10W-40, 10W-50
Above -7C......20W-40, 20W-50

CAPACITIES:
Engine, without filter..........3.8 liters Add extra oil when replacing filter. After refill check oil level.

Use Lucas oil treatment and use the 10W-40, if your going to use the 20W-50. Use no oil treatment, the 20W-50 is thick enough. 15W-40 is what's used on the Diesel engines use on the 18 wheel trucks.

Thank you for using fixya.

Driving conditions / oil

(Note all oils are NON-DETERGENT)

City hot / SAE 20W - 50
City warm / SAE 10W - 40
City cold / SAE 5 -30 or 5W-40

Rural hot / SAE 20W - 50
Rural warm / SAE 10W - 40
Rural cold / SAE 5W - 30

Brand does not really matter as the SAE designation makes them all the same other than a few manufacturer specific additives i.e Techron ect.

since your car is older and mileage is high i recommend using 10w40 high mileage oil and and takes 5 quarts.hope this is what you wanted.

SAE 5W-30 or 10W-30 will cover colder temps and most warmer temps. 10W-40 is a good choice in hot months - just make sure they are a high detergent ( most are nowadays)

for an 87 I can imagine that you are probably running it at between 175K-350K miles so you should be getting

Castrol/1 qt. SAE 5W-30 GTX superior sludge protection motor oil

Part Number:
12082

It probably wont hurt to use a high mileage oil or even a 10W-40. Most cars use 10W-30 but if your car has a few miles on it it may help to use a higher mileage formula or even synthetic. You may want to try a slightly heavier oil like 15W-30 or 40.

LUBRICANTS & FLUIDS
Engine Oil
Grade 1......SL
SAE 0W-30 Synthetic Signature Series Oil
Synthetic 5W-40 European Engine Oil
SAE 10W-40 Synthetic High Performance Motor Oil
SAE 5W-30 XL Synthetic Motor Oil
Above 5°F......15W-40, 15W-50
Above -4°F......10W-30, 10W-40, 10W-50, 10W-60
Above 23°F......20W-40, 20W-50

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