6.3
fairly significant- Typical Repair Cost:
- No data
- Average Mileage:
- 79,300 miles
- Total Complaints:
- 6 complaints
Most common solutions:
- not sure (4 reports)
- balance timing chain & fuel pump cover (1 reports)
- replaced both timing chains & camshaft actuators (1 reports)
This problem may be covered under warranty. Ask your GMC dealer.
Once again car was making loud noise upon start up and at idle. Dealer found both timing chains loose and had damaged both camshaft actuators. Replaced both timing chains, camshaft actuators and chain guides. Covered under special policy 12313.
- shereer, Post Falls, ID, US
This problem has existed long since the original warranty expired. I am afraid of what might happened after reading other complaints but will be having it checked out anyway.
- Derek C., Apple Valley, CA, US
the engine is very noisy - they replaced tons of stuff, timing chain, sensors, more than I can remember, even some kind of muffler to keep the noise down. That was within the first year we owned it--the noise is still with us, and getting louder. I asked a few weeks ago and they said there is nothing else they can do. We are nearing 70,000 miles and worried something will go wrong, or we won't get much trading it in.
It sounds like a loud diesel engine. In fact, twice at a car wash at the dealers, a worker out for a smoke came up and told me I needed to have it looked at it was so loud. They were sure something bad was wrong. We did get a letter saying they have extended the warranty to 10 yr. 120,000 miles for this problem. In the meantime it is loud and annoying.
Update from Aug 4, 2014: I called GM the day I posted this and received a call back very soon. My terrain is at the dealer being looked at now. Was very pleased with such a quick response, and even a follow up call the next day. Will update when I know more:)
- lwren, Moline, IL, US
The car still has fairly low mileage (40,000) to be having a rattling engine. Seemed like it was fixed though I've heard some rattles when starting occasionally again.
- Peter P., Concord, NH, US
![](http://cdn.carcomplaints.com/img/icons/play-overlay.png)
I have scoured the internet for a fix. I've searched forums and have come up with the conclusion that GM does not know how to fix the problem.
The dealer could not reproduce the issues with my car so they didn't attempt a fix. The tech did try to tell me that the oil was low but I had checked it the day before and it was fine. After I told the service writer he personally checked it and agreed it was properly maintained.
Some of my fellow owners on the forums have had timing chains, cam phasers, chain tensioners, fuel pumps replaced but the issue generally comes back.
- vw1610, Torrance, CA, US
Car was making a loud rattling noise upon startup, and sometimes after driving a while. Almost sounded like a diesel. Dealer confirmed engine rattle coming from timing chain. Balance chain & fuel pump cover under policy 12313.
- shereer, Post Falls, ID, US