7th Nov 2006, 11:52

Our 2003 Envoy has proven to be the best vehicle we have ever owned. It is powerful, smooth and has never had a sinlge problem in almost 60,000 miles so far. On a recent trip on the interstate I set the cruise on the speed limit (70) and got an incredible 24 miles per gallon. That is actually BETTER than my 4-cylinder truck. We absolutely love this car and will definitely buy GM next time. Of course, that may be a while, as we plan to keep this one for many more years yet.

4th Dec 2006, 08:08

I'm wanting to get better mileage from my Envoy. Presently I think replacing the cold-air intake with any one of many aftermarket products will be the best way to accomplish my goal. Will you all in the ether-world please send me you knowledge of this change. I specifically want answers on 1) Has your dealer turn back all warranty work since getting a non-OEM cold-air intake? Vary dealer to dealer? 2) What product have you used? What mileage increase did you see? 3) Installation issues? I'd like to keep the comments in the facts-only world. Speculation is not usually helpful.

4th Dec 2006, 12:51

If you have Onstar they may notice the change... be careful.

7th Feb 2007, 15:36

I have a LWB V8 model and get 14-18 mpg. Am thinking of installing cold air intake. Any comments/info?

P.S. These vehicles will never handle like sports cars, but replacing OEM tires (especially Continentals) can make a big difference.

14th Mar 2007, 21:48

The cold air intake can throw off the computer and show up as a trouble code. Dealers are different in regards to warranty stuff. I ALWAYS go and talk to my service manager where I get warranty work done before making any changes.

All I have done to our Envoy is switch to full synthetic oil (helps to reduce friction minutely, can add fractionally to mileage) and install a K&N high-flow air filter (this you don't even need to worry about, it won't affect the warranty at all).

We are getting between 18 and 20 mpg in town with our in line 6 Envoy, and around 23 to 25 on trips. That is using the cruise control on trips and driving at the posted limit, but does include using the air. We are very pleased with the mileage we are getting with such a big vehicle.

We've also never had a second's trouble with this vehicle, and at 50,000 miles+, it feels like it did the day we drove it home. It's definitely a keeper.