I know this question has been asked before but i haven't found the answer by searching.

I want to get 350Z Tein H-Tech's for my G35 with 35,000 miles on it. Do I need Aftermarket shocks now too? Or will I be ok with the stock ones?

 

You don't absolutely need them, a lot of people here just swap springs and nothing else. You can ride out your stock shocks until they are dead. At which point look into Tokico D-Spec shocks which most people tend to use in conjunction with the Tein springs.

 

Anyone know how long they typically last with those springs

 

impossible to say with any accuracy. how many miles currently, what roads do you drive on, how hard do you drive, do you have people or loads in your car etc.

 

Is there a range, even if it's a wide one?

 

Not really. Like RBull said there is no real estimate. They could last a couple hundred miles. they could last you 30,000. It all depends. hooters

 

how do u know if its time to change out your shocks?

 

usually when shocks wear out, at least for me, on the interstate you'll notice your car bounces a lot more when going over bumps and joints in the road.

 

Yup.