Okay, so if a friend with a 2.2 wanted my stock suspension would my springs change straight over to his car and if so, would it be a good upgrade for him? Thinking about getting some sportlines soon...

 

daytime bump.

 

I'm pretty sure I've read on here that all suspension parts are interchangeable between all cobalt models

 

cool. thanks.

 

Taken from the Suspension and Brake facts thread at the top:
So far, and to the best of our collective knowledge, every single suspension part is completely interchangable between models. Some rules apply, which are listed here:

1. If you change the front anti-sway bar, you must be careful to get the proper model year. As explained below by Maven, the FE5 front bar mounting changed between 2005-06. It appears the simple trick it to just get the 2005 FE5 parts to insure compatibility.

2. You can change the rear FE1 axle to an FE5 axle. The FE5 axle has provisions for mounting rear disk brakes. So you either have to cut those off to put on your drums back on, or you have to convert to rear disks. Converting to rear disks does NOT mean you have to convert to 5 lug hubs, but you are going to have to find some 4-lug rotors!

3. Knuckles are the same on every suspension up through 2007. In 2008, the FE5 knuckle was updated with various improvements for bump steer. It is NOT interchangeable. You can still use the GM Racing knuckles for those earlier years

4. Every other part should be completely compatible. For instance, you don't have to use FE1 struts if you want to put on FE5 springs, and so forth.