Thread: What to look out for on GXP models?

Thanks for the input buickman! I will keep all of that information in mind. Looks like the intake is K & N?

Did not even notice the difference in the tires, but being a FWD v8 I am expecting the tires to have a very short life lol

Originally Posted by buickman104

Pay close attention to transmission temps not looking for it to go past 200 degrees. Also have a transmission service done on the car. As you can imagine on the GXP models the transmission is the weakest link.

If you plan to keep the car long term it is recommended to add an auxiliary transmission cooler.

Also those look like aftermarket head and tail lights. You will want to make sure they were properly wired and it is known that aftermarket headlights have horrible night time output.

Also keep in mind that the front tires are wider than the rears. When replacing tires most folks like to go with 245/45/18 size tires all around so they may rotate them.

Also has an aftermarket cold air intake so the previous owner might not have been gentle since he/she was looking for more performance. Check transmission fluid for color and smell. You want it to be bright red and have no burnt smell. If it is brown and has a burn smell the trans might not be in the best of shape.

Originally Posted by buickman104

Pay close attention to transmission temps not looking for it to go past 200 degrees. Also have a transmission service done on the car. As you can imagine on the GXP models the transmission is the weakest link.

If you plan to keep the car long term it is recommended to add an auxiliary transmission cooler.

Also those look like aftermarket head and tail lights. You will want to make sure they were properly wired and it is known that aftermarket headlights have horrible night time output.

Also keep in mind that the front tires are wider than the rears. When replacing tires most folks like to go with 245/45/18 size tires all around so they may rotate them.

Also has an aftermarket cold air intake so the previous owner might not have been gentle since he/she was looking for more performance. Check transmission fluid for color and smell. You want it to be bright red and have no burnt smell. If it is brown and has a burn smell the trans might not be in the best of shape.

This exactly. I am new to the GXP world and love it! Great cars, just need to be aware of the trans. Every car has their known problems so don't let it steer you otherwise.

If you ever have questions about the transmission there is plenty info on here as well as contact Dave over at TEP (triple edge performance). I just did and I'm think inking in awhile I'm gonna make the drive from Detroit to Fort Wayne and have him rebuild and beef up my trans just to bulletproof it before anything happens.

The V8 engine comes with "Displacement on Demand" ( later called Active Fuel Management) which puts the engine into 4 cyl mode when cruising. This makes the engine use a little oil. It's not a deal breaker, just be aware that it will use some. Make sure the rims say "Alcoa". Always wanted those on my GT. Nice car.

Originally Posted by Russosaur

You want to get DoD tuned out because its not good on the TC iirc.

Sent from my Galaxy Tab 3 8.0

My DoD has been tuned so that it only occurs in 4th on the highway. I make a lot of 3 hour trips and it's nice to know I'm saving at lease some gas...lol.

But I agree with Russ's 3 commandments. Although I'm only following two at the moment

Thanks for all the comments guys

I am excited

Interesting, why were they built with different widths?

When you guys say transmission service, do you mean just a routine flush or are you referring to something more invasive?

Also, I will try to search around and look into the trans coolers...Got an estimate of what one would run (installed)?

Originally Posted by 91parkave

Side note...even if you have the same size tires the rims them selves are different widths. Its just the nature of how the car was built.


Like everyone else has already said do not go cheap on maintnence get the trans work done...don't wait especially before summer. Those stupid high trans temps coupled with dod and stock transmission settings will eat it alive very quickly..

Have fun with the car and feel free to reach out for help

The wider rims in the front are GM's answer to tourque steer. Because it is a FWD V8, it will tend to pull to the side on heavy acceleration and traction loss. The idea of the wider rims in front is that the rear should lose traction first, reducing torque steer. I'm don't really have an answer on how effective it really is.

Just my opinion really, but I'd personally never flush a transmission. Definitely drop the pan and change the filter, but machine flushes tend to break more than they fix. I have heard it depends on how the machine flushes it, but I've never had good experiences with them. My mother got the transmission flushed on her vehicle when I was younger, and it gave out on us while we were going up a hill the next month.