ENGINE SMEELS HOT AFTER DRIVING ANY DISTANCE.

you did not post in what country and what climate,

if you are in oz, then any oil sae10-40, it is suitable year round,

if you live somewhere where water freeze in winter then winter oil should be sae 5-30, or sae5-40, summer should be sae 10-40,

if you live in tropics where temperature constantly exceed 35c (95f), then oil used should be sae15-60 or even sae20-60.

any brand will do, my preference is semi-synthetics in cars made after 1985, if car is working hard - towing, driving daily short distances - i do change oil and oil filter every 5000km (3000miles), if it is driven regularly and in light conditions you can double these distances.

if you find this answer helpful - why do not vote for it?

http://www.automedia.com/Degrease_Your_Engine/ccr20050701de/1

Follow this procedure and you will have good results.
Good luck, i hope this helps.

if its a white or caramel colour then it is moisture in the oil.if you do alot of short trips and the motor oil doesn`t get hot enough then condensation will form in the oil system.this is normal for those that drive only short distances.the only way to get rid of it is to drive farther and make sure the oils gets hot enough to burn off the condensation or change your oil.if you run an oil system cleaner through the oil when you get the oil change this should remove all of this if not most of it.

Well they need to say why it failed ( unburned hydro carbons?) Check engine light on?, Visable smoke? Nitrogen oxide levels too high? If the light is'nt on and the truck runs good make sure the engine is good and warmewd up as you take it to be inspected. If you have to wait in line to be tested rev the engine at a faster than normal isel as you wait. a freash oil chage will also help. new spark plugs and any other overlooked for mileage driven services to up dated. engines that run too cool as the therostaate not leting the motor get hot enough to burn the fuel good. The air filter not being clean. turn the base idel up as high as you can drive it Ok. Maybe with these things followed it'll pass check and adjust the inghtion timing or set a little higher than stock may push this old motor to pass. Go to the test when their real busy and maybe they won't run all the tests and not catch the reson you failed this last time. Adjust the fuel mixture screw on the side of the carb to the smoothest possible idel and then screw it in till it just slows down and then turn the idel screw back up just enough to have it run at the same speed it ran smoothest at and smeel the ezhaust to see if you can smeel fuel if you can the fuel pump may be leaking fuel into the oil and it's showing up on the test.The fresh oil change may cover this as you take it to the test right after you change the oil. Ifthe oil smells like gas you know for shure but it might pass anyway if it's clean enough.

Oil filter is provided by year,make, model of your vehicle at the parts store. ---
Oil and fluids Oil quality
Engine oil must meet the minimum ILSAC specification GF-2, including ACEA A1, API SJ, SJ/CF and SJ/Energy Conserving.
Your Volvo has been certified to standards using ILSAC oil specification GF-2 5W-30. Volvo recommends use of oil with a quality rating equal to or higher than ILSAC GF-2. Equivalent and better oils include ACEA A1, API SJ, SJ/CF, and SJ/Energy conserving. Lower quality oils may not offer the same fuel economy, engine performance, or engine protection.
Volvo Cars recommends Castrol. Depending on your driving habits, premium or synthetic oils may provide superior fuel economy and engine protection. Consult your Volvo retailer for recommendations on premium or synthetic oils. Oil additives must not be used. NOTE: Synthetic oil is not used when the oil is changed at the normal maintenance is carried out. This oil is only used at customer request, at additional charge. Please consult your Volvo retailer. Operation in hot climates.
When temperatures exceed 86° F (30° C) in your area, Volvo recommends, for the protection of your engine, that you use a heavier weight oil, such as SAE 10W-30. See the viscosity chart below. Oil viscosity (stable ambient temperatures)
Operation in temperate climates
Incorrect viscosity oil can shorten engine life. Under normal use when temperatures do not exceed 86° F (30° C), SAE 5W-30 will provide good fuel economy and engine protection. See the viscosity chart above. Extreme engine operation
Synthetic oils meeting SAE 10W-30 and complying with oil quality requirements are recommended for driving in areas of sustained temperature extremes (hot or cold), when towing a trailer over long distances, and for prolonged driving in mountainous areas. Changing oil and oil filter
Oil and oil filter changes should be made at 7,500 mile (12,000 km) intervals. Volvo does not recommend the use of oil additives.
Synthetic oil is not used when the oil is changed at the normal maintenance intervals except at ower request and at additional charge. Please consult your Volvo retailer.

Some smell is normal if it has been quite sometime between oil changes. This happens more with short distance driving.

How does it get there?

Through cylinder blow by when the engine is cold. The piston rings leak minuscule amounts into the oil which add up over time.

If you are having no other running issues (IE black/drk grey smoke out tail pipe with oil residue on pipe tip) I would not be alarmed by this.

Check the engine for oil leaks. More than likely oil is dripping on the hot exhaust pipe which causes the oil burnt smell.

If you have recently changed or had the oil changed I would suspect a bad filter or the old oil filter gasket still on the filter boss and a new filter with an additional gasket installed on top of the old gasket. Usually in a short time the old filter gasket will blow out causing a massive oil leak. To locate the leak fill the engine back to the full mark with oil and start it and look for the leak.

Get the wright oil for the hot weather.Go to your dealers and they will advise you on what oil to use.It seems like you have the wrong grade of oil in the car for the hot condtions.hope that was helpfull.

change engine oil and filter every 3000 miles.if car is under severe conditions.like. long idling.dusty condition.short running conditions.not letting engine get operating temp.hot climate or temperature.the maintenance intervals said you can change engine oil at 7500 miles.if its not under harsh conditions.