My 2007 tahoe with 40,000 km on the odometer doesnt give much power as before ,, just change parts or serious?

Question

i want to know if it just needs new engine parts or if its something abit more serious cuz even though GM says that it needs atleast 87 octane and i've been filling it up with 91 octane gas the dealership said i should fill it up with 95 octane gas :S

Answer 1

There's no way a Tahoe should need 95 Octane gas. Most gas stations don't even have higher than 93. (are we talking in the US here?) In fact, the 91 Octane gas could be part of the problem. Higher Octane than needed does no good, and can actually reduce performance. Try some 87 for a while, and see what happens.

Other than that, start with the simple stuff. If the Air Filter has never been changed for example, would be a good place to start. That and oil changes are about all you should need at this low mileage, unless something is defective. And if it's something that affects emissions, the dealer is obligated to fix it any time before at least 50K miles.