GTO Gas Mileage

[ChevyMan]

Does anyone have any ideas why the GTO gets such bad highway MPG? The Corvette with the same 6.0 liter engine gets an EPA estimated 18/28, but the GTO gets an EPA estimated 16/21. I realize that the Corvette is approximately 500 pounds lighter, but that hardly seems like enough weight to offset the difference in MPG. The axle ratios for both are pretty similar, so I'm kind of scratching my head.

I am considering buying a GTO, but with gas prices as high as they are I would like to hear from someone that owns one to find out what kind of gas mileage they are averaging.

[Northstar]

I have one (04 A4). On this tank of gas I'm gettting 14.5 MPG (all in the city) but I usually get 14.0. I don't take it on the highway much, but mine gets about 20MPG. I have a performance camshaft however, so that probably brings the MPGs down a little.

I would go for the M6 (would have gotten one but my dad wouldn't get a manual) if you're looking for gas mileage. I think it's rated at 25MPG on the highway.

The main reason it gets bad mileage is the weight. At 3700+ pounds (without the driver), it's significantly heavier than the Corvette.

[ChevyMan]

Thanks for the response!

I was thinking of getting the 6-speed manual tranny, but I hadn't seen the EPA estimates for that. If it gets about 25 MPG on the highway that would be great! I guess I'll have to go down to the dealership to check them out.

[Northstar]

The manual gets 17/25 and the auto gets 16/21.

I don't know if you're set on an '06 or not, but if you can find a new '05 on the lot you can probably get it for ~$25k (and if you have GM Card points even less). If you can find a good used '04 (less than 10k miles) then you can get it for around $20k (got mine for $21k with 6k miles in Feb.).

If you have any other questions let me know. There are some problems with wheels and tires (if you go aftermarket) that you'll want to know about first.

[ChevyMan]

What's the issue with aftermarket wheels and tires?

[Northstar]

Well, there are certain tires that rub even though they are the same size. For instance if you get 17s (they're P245/45ZR17) and need new tires, some brands aren't exactly the same as others and rub. Pirelli P Zero Nero M+S's rub and you have to get them in 235/45ZR17. Even though the numbers would say the sidewall is smaller, it ends up being the same (and you don't have to adjust the speedo). There are other similar issues like that. If you want wider than 275s out back you will have to get the fenders rolled as well.

Basically, just be careful and make sure the tires aren't rubbing in any way if you get new tires. LS1GTO.com has a ton of info on any and all problems with tires/wheels.

[ChevyMan]

Thanks for the heads up! What tires do you currently have on your GTO?

[Northstar]

Currently I just have the BFG KDWS P245/45ZR17s, but they aren't that great. I'd probably go for the Pirellis, but if you are going to get new tires definetly ask the guys at LS1GTO.com