I searched on this
I have as most know a2009 hhr ss with a 3year 36k warranty pretty much bumper to bumper warranty.

the real questions I have are as follows

• Can I change the Coolant myself or will this void the warranty
• Can I change the spark plugs myself
• can I change the serptine belt myself
• do all of the parts that I change have to be AC delco oem example I think the gatorback serpentine belt would be better.
• and basically any other things as far as maintenance can I do that all myself or is there set mileage points say 75000 where gm has to go and change certain things
• I know I can look in the owners manual but as we all know the dealers usually say that is not for extreme conditions such as living in the northeast

any advice would be great

 

None of those items are covered under any warranty so the answer is no, you will not jeopardize your warranty.

However, keep a journal of any services you perform and receipts for the parts. A physical service record could help you if you do need warranty work in the future.

 

None of those things should have to be changed within 3 years or 36000 miles........

 

my warranty started on a 50,000 mile used car
nothing like having close to a new car warranty on a used vehicle
it has come in very handy.

 

Nice Mike, good piece of mind there with the extended!