Joined: 01-09-2007

Posts: 15,984

From: SE USA

Joined: 03-22-2010

Posts: 74

From: Minsk,Belarus

Joined: 10-13-2011

Posts: 37,843

From: Welland,Ont Canada

In here it’s discussed, no real interval , just cheaper to change the chains and guides , then replace bent valves or damaged pistons , or complete engine.
after 125,000 miles you have to ask yourself, do you feel lucky? Well do you?

Joined: 03-22-2010

Posts: 74

From: Minsk,Belarus

Joined: 10-13-2011

Posts: 37,843

From: Welland,Ont Canada

At that mileage, if you take it apart to check, continue and change the timing and balance shaft chains.

https://www.chevyhhr.net/forums/how-...in-kits-60394/

Joined: 01-05-2021

Posts: 6

From: Indiana

Joined: 01-09-2007

Posts: 15,984

From: SE USA