Timing Chain Issues - Insight? [Archive] - Pontiac G8 Forum: G8 Forums - G8Board.com

: Timing Chain Issues - Insight?

Bad Karma
06-29-2010, 10:39 PM
I have a 2008 V6 with about 34,000mi on it. I had a Check Engine light come on last week, took it to the dealership for service today, and they said the timing chain was loose/causing the issue.

Any idea why a timing chain that is supposed to last the life of the vehicle would have problems this early on? I do drive my car hard, and put nearly 1000 miles a week on her, but I only run full synthetic oil (Mobil1) and have it serviced regularly or more than regularly. Typical drivng habits include hours at a time spent at cruising speed (~70), fast, but generally not WOT acceleration, etc.

06-30-2010, 01:22 AM

Bad Karma
06-30-2010, 02:05 AM
I will be taking it back in next week to have the issue corrected under warranty and will provide you all with further information as I get it.

06-30-2010, 02:59 AM
Maybe a tensioner issue, even the V8's have issue with those (from what i have read on the holy grail).

06-30-2010, 09:21 AM
The chains on the LY7 are stretching. We had a big problem with them on Caddy's. Let me guess, you got a P0008.

Bad Karma
06-30-2010, 04:01 PM
The chains on the LY7 are stretching. We had a big problem with them on Caddy's. Let me guess, you got a P0008.

Talked to my technician over at the dealer today and that's basically what he told me. There is a GM bulletin for the LY7 chains and they are going to replace the primary and secondary chains with revised models under warranty.

For the rest of you V6ers, maybe it's something to consider having them look at, especially if you're getting a CEL or having issues with acceleration response. For me, if I was at cruising speeds and demanded WOT from the engine for whatever reason, it would hesitating for a second or two before finally downshifting and accelerating.

06-30-2010, 05:19 PM
Actually they arent revised chains. I just sold 7 primary and 14 secondary to another dealer just to get rid of them because my dealer closed on Friday.

Bad Karma
06-30-2010, 05:37 PM
That's lame. So I can expect to have this issue every 35k then? Good one, GM. Are there aftermarket chains available?

06-30-2010, 07:50 PM
There has been many threads on this issue and I could of sworn that the fix was a different chain.

06-30-2010, 10:30 PM
Same chains atleast same part numbers. I seen stretched chains on CTS's and STS's with less than 10000 miles. I think it might have something to do with oil changes, but Im only speculating. Either wrong type of oil (Caddies require synthetic) or too many miles between changes.

07-01-2010, 08:34 PM
Oh, wow. Just something else to be concerned about. I must admit, I drive the pony somewhat hard at times. If anything is going out or lose, I want it to be before the 36K mark. But, I will definately have to research this a bit more. Hopefully, the chains are somewhat better. I went from 5W-30 to 10W-30 oil. Changing it back next oil change and baby the car a little more, need her to last quite awhile. Good luck.

07-01-2010, 10:25 PM
Why worry about 36K. The drivetrain is warrantied to 100k.

07-01-2010, 10:33 PM
I had an LY7 in my G6 and never had problems with the timing chains and I drove it hard and had it modded.

07-02-2010, 04:47 PM
So is this covered by the 100k drivetrain warranty?

Bad Karma
07-02-2010, 07:26 PM
Yes, it is. Interesting speculation about the oil changes. I do mine every five thousand on the money, full synthetic 5W30 Mobil1. I run her hard, but I baby her. Perhaps the previous owner who put 20,000mi on her wasn't quite as caring?

07-07-2010, 01:23 PM
Here is my thread on the same issue for the caddy


07-09-2010, 09:54 PM
why worry about 36k. The drivetrain is warrantied to 100k.

ok. Thanks. Now i can resume my stock car driving.

07-09-2010, 11:25 PM
That's lame. So I can expect to have this issue every 35k then? Good one, GM. Are there aftermarket chains available?

actually no, the chain problem was because of a poorly made batch of chains from a specific supplier. GM fixed the problem by have the supplier correct the mfg problem and resupply the chain. FYI from my research there are two separate problems.

the first gen caddy's (LY7) guessing 04-06 had a chain stretching problem. There seems to be another problem with the 07-08 models which has something to do with the chain/cam design. I keep reading stories of dealers having to add shims to the cams to stop end play.

Autozone supplies a full kit which replaces chains, gears and tensioner. I did some research and the kit is made by Cloyes. They seem to be a reputable GM parts mfg, I also think they make OEM parts.

07-10-2010, 09:53 AM
You are right about the cam washers.

07-14-2010, 12:42 PM
I just picked up a Timing chain set from autozone. Did some research the product is made by Cloyes, and is in fact a repackaged OEM kit. I'm really happy with how complete the set is. Individually purchased online it would be in excess of $400. see pictures below.

as it comes in the box

side by side tensioner bracket

all new tensioners w/ gaskets

side by side gears, same part number etc.