It probably did not have an oil change in a long, long, time and all that smoke coming out was the sludge left inside burning. Add oil and then drive it to a repair station to change the oil and filter.
Have you checked your transmission fluid level, lately????
There is no standard level 3 background check but it will usually be more comprehensive that a level 1 or level 2 background check. The exact things that are checked in a level 3 background check are determined by the company.
check coolent level
Check your coolant level.
check your oil level?
Check the fluid level and have the computer checked for codes.
Trans fluid is always checked with car level and idling while warmed up.
If it is an automatic transmission, then it should have a dipstick to check the fluid level. Depending on the make and model, the location of this dipstick will vary. If it is a manual transmission, then the fluid level really can't be checked and it will not have a dipstick.
Check the level in the overflow bottle. If it is full the level sensor may be bad.
If it is the LG8 engine V6 it has what is called a check bolt on the transmission housing. The vehicle has to be on a hoist and level in order to check fluid level from underneath the vehicle. The check bolt must be removed and the level checked in this manner. The dipstck was done away with probably in order to get more business for service centers.
first check your coolant level. then check to see if you have a leak, then check to see if you cooling fans are coming on then check if your thermostat is working.
Check the fluid level. If it is low, it may be slipping.