Changing factory wheels from 17" to 20"

I have a Chevy 2007 LT . It came with the 17" chromed factory wheels . I bought the 20" Texas edition factory wheels and tires from a friend .
Do I need to do any changes on the suspension , springs before I swap them ?
Will it affect the life of the suspension if I do nothing ?

No, not really.. You will be fine. Not really anything you need to do

You may need to recalibrate the speedo, depending on the size tires you put on.

Assuming that these 20" wheels are wider than the 17", there will probably be a need for an alignment. I had stock 17s on my 04 and then put on a set of 20" Chrome Denali wheels (which are for sale if anyone is interested) and it looked like the wheels were cutting into the pavement. As for the speedo, there wasnt all that much of a difference in the tire size so it didnt make all that much of a difference with the speedo. The only thing I would imagine could possibly be affected would be the brakes seeing that you are now stopping a larger (and probably heavier?) wheel which means more effort from the brakes. Thats what I found when switching wheels.

Did you noticed a stiffer ride when you swapped for the Denali's ?
That's something I'm kinda feeling .. but I don't know if it's just me .
The tires are wider than the 17" . Have you seen the Texas Edition wheels yet ?
Thanks for the advice

Yes, those wheels are very nice. Infact, they look very similar to the set that I have except that mine are the older design that you could order with the Denali package around 03 I think. As for the ride, there is definitely a much stiffer ride. The ride is a little smoother on a smooth road than it was with my All-Terrains but you certainly feel every single bump you hit. But, this is only expected with any lager diameter wheel so its nothing to worry about unless its something that bothers you. And now that I think of it, the main reason I went to get an alignment when I put on the 20's was because I had to adjust the torsion bar back down to stock level because they were cranked to bring the front up to fit the all-terrains I have.

How much are you asking for the 20" DENALI's ?
THere's probably someone that might be interested on them .
Thanks

I'm looking for $1600 but thats not exactly firm. They come with Chrome lugs GMC center caps and the tires are still excellent with good tread remaining. I can get pictures to anyone that is interested.