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Alex, ASE Certified Technician
Category: Chevy
Satisfied Customers: 1161
Experience:  ASE Certified Master Technician, L1 Advanced Level Specialist
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I have engine knock that comes and goes. It will sometimes be there when I start the vehi

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I have engine knock that comes and goes. It will sometimes be there when I start the vehicle, and sometimes not. It may come on driving at highway speeds, but not all the time. It may come on when the engine is idling. I brought it to a shop and they put all new lifters in the engine. Did not help the problem. There are 170,000 miles on the engine. Mostly highway miles. Never had a problem with the engine before this.

I am wondering what is the cause of this problem and how I can solve it.

2006 Chevy Tahoe, 5.3 liter V-8.

Hello. My name is XXXXX XXXXX I'll be assisting you with your question.

The problem is most likely one or more worn camshaft lobes. The lifter rides on the camshaft lobe and the lifter and the lobe can wear over time. They should have inspected the camshaft lobes for wear when replacing the lifters and replace the camshafts if necessary. If the lobes are worn, replacing the lifter will not cure the noise.
Alex and 2 other Chevy Specialists are ready to help you
Customer: replied 4 years ago.

What is the approximate cost to replace the camshafts?

Also, if not done, will it cause damage to the engine?



The engine has one camshaft and it is a time consuming job at 17 hours labor time. Most shops charge around $100 per hour so labor alone would be around $1700. The price of the camshaft itself is $350-$400 at most Chevy parts counters.

The camshaft lobes being worn can potentially cause other parts of the valvetrain to wear over time. It may also cause the engine to run at a lower level of efficiency. If the camshaft is worn, it would be a good idea to have it replaced as soon as possible if you plan to keep the vehicle for a while.