It may have to do with the fact that I drove the gxp solo. I played around a little more with it while i just "daily drove" the rl because of the poor terrified carmax agent that got stuck with me. The gxp also only has 15k miles while the rl has double that. The only thing im concerned about so far is the gxp had 2 owners with only 15k miles. The first one drove 12k and the second drove 3k and then traded it in. Also if I was in too high of a gear and gave it gas, sometimes it would shudder a bit then just resume a slow acceleration. Its a black 2007 gxp in fairfax va if anyone here owned it before. Also i did find the only manual 2008 available in my area, but it has 60k miles. Is this too much for a 2008?
You can still find 06 cars with less than 5k miles on them. These cars in the main are "toys" and tend to be garage queens. They come out in good weather and get put to bed when the weather gets bad. Having low mileage is not a bad thing with these cars.
We had one club member who put 160 miles on his car in the first two years of ownership. Yes, 160 miles. He had the car 24 months and never bought gas for it.
The 2.0 turbo motors are designed to rev. I never drive mine under any kind of loading below 2500 RPM and am happy to cruise around at 3500 in a lower gear just to keep the thing turning in its happy place. While they make a lot of HP and torque, they are not happy being lugged down. Only bad can come of high throttle at low RPMs.
Also, the ECM tunes on the fly. If you are crusing along at low power settings for any appraciable time period, then whack the throttle wide open they will frequently complain as you have noticed. This is because they adjust for a nice lean cruise mode to return 30 plus MPG. When you hit them with high power demands suddenly they take a bit of time to recognize the demand, and then adjust the settings to provide that power. This can be evidenced by some slight knock, a bit of sluggish by comparison power delivery. If you go more gradually to the first high demand setting, then whack the throttle WFO it will kick you in the seat of your pants.
Under the skin, the NAs are basically all the same. The turbo cars fall into three catagories, each very similar. The cars through about mid-production of 07 have the early cable set so steering wheels from post mid-07 will not fit the earlier cars without a lot of modificaiton for example.
Starting with early 08 production, the vacume pump was eliminated so if you get an early production 08 of either variety it will not have the electric vacume boost pump. Mid-08 and on all have the pump included again.
I have read that late 09s and the 10s have different ECM software that is incompatible with the GMPP stage tune. I am sure Soup will provide more details.
Basically the "ideal" car is mid-07 RL or GXP with the updated wiring. Not early 08 without the vacume boost pump. And not very late production.
As far as mileage is concerned, NAs are running around with well over 100k miles and going strong. I read about one that is over twice that and still going.
If it has pronounce gear whine from the rearend, consider looking elswhere. A small number of cars have had problems with the differential.
Anything below 25-30 k miles in my experience is a great find. If it has more than that, its not a bad thing as long as it has been properly maintained.
Pull a record of the car from the GM database at any dealer and find out what and when maintenance was performed. Look for recall on the differential having been performed. Verify if it has the GMPP tune and if it does verify that the crimp connectors are soldered or that it is a later kit with soldered connectors.
The "expected" expensive things that you can anticipate if you own the car long enough are
1) Water pump any time after 25k miles (lots of threads about how this must be done correctly or it can screw up the cam drive chain)
2) High pressure fuel pump - small number of failures but it costs about $600 to get repaired and not something you can do for yourself as you have to bleed the high pressure fuel delivery system post pump and its dangerous as well as demanding
3) Slave cylinder / throughout bearing assembly. There are two designs, an early and late design. The early design has experienced some failures of the delivery hose which requires ~ $1300 to R&R the transmission, clutch, pressure plate and the throughout mechanism.
Other than that, read every post on this forum and you will be good to go