First you need to determine what type of transmission you have; automatic, CVT or standard. You can consult your owner’s manual, Dealership, or a reliable transmission facility. In any case you typically have two types of transmission fluid for three types of transmissions; Conventional or Synthetic.
Conventional fluids are less expensive, provide the minimum protection needed for your transmission as specified by the manufacture, they have a high petroleum content, break down sooner, create sludge, varnishing and need to be changed more often (within 30,000 miles or less service intervals.)
Synthetic fluids are more expensive, provide the transmission with far superior protection above and beyond the manufacture specifications, protects longer than conventional fluid, has no varnish or sludge build up requiring fewer changes (up to 60,000 mile service intervals under normal use.)
As you can see, synthetic fluid can save you maintenance time, money, and greatly increases your odds of never having a transmission failure.
In our opinion BG is one of the very best automotive fluid product companies in the USA. They state that even their synthetic transmission fluid breaks down and should be serviced by the time it reaches 60,000 miles. They have tested the OEM transmission fluids that come in your new vehicle and found that it could not properly protect the transmission after 30,000 miles. So the question is this, why is it that when buying a vehicle so many people are being told that their vehicles do not need a transmission service until 100,000 miles? This is what we were told by some very reliable sources: There are companies that that will boast that they have the least expensive vehicle to operate over a 100,000 mile period. In hopes of attracting new customers and fleet accounts, manufacturers are increasing the time and mileage suggested between maintenance services. If the consumer believes that it is not necessary to perform maintenance on their vehicle as often, it will cost less to own. But the downside to that is if they decide to keep it beyond that mileage, you very well may be putting some big dollars into your vehicle anyway.
BG laboratories tested multiple brands and types of fluids. The conclusion drawn by BG was that even the name brand synthetic fluids, failed far sooner than the factory suggested maintenance change requirements. In fact, most of them failed terribly within 30,000 miles, which means that you would be driving your vehicle with very little protection, if any, until you reached 100,000 miles. We trust BG’s opinion on lubrication products and you should too.