GMC Denali Timing Chain

We’ve got a 2002 Yukon XL Denali with the standard V-8 engine with 130,000 miles on it. I called the dealer we’ve used and asked about their recommended interval for timing chain replacement and was told “We don’t have one, we don’t see many problems with timing chains.” Sounds odd to me, anyone have any experience with these engines?

This engine has the cam in the V of the block i.e. it is an overhead valve push rod engine. Usually the timing chain and gears are a life of engine item. At very high mileage or following poor oil maintenence the chain and gears will wear enough that there is enough slop that the valve timing is erratic; possibly the chain may hit the chain cover; or the chain will jump with poor running following. A good mechanic can check the slop in the chain gear assembly and assess the condition of the cam drive.

If I were to set a chain replacement mileage, it would be 200K miles or whenever I had the chain cover off for other work, like a new cam and lifters.

Hope this helps.

The standard GM V8 has always had a timing chain and they often last as long as the car. The secret is regular oil changes and using the right grade of oil. Also, keeping the oil level checked.

I had to replace one on a 305 V8 at 165,000 miles, not because it broke but because it started making growling noises, indicating it was wearing out. The chain and gear set are sold and replaced together. Mine cost $250 but that was 9 years ago.

So, the dealer is right; when chains need replacing the owner has long ago stopped having his vehicle serviced at the dealer. Dealers seldom see such a repair job. Go to a good independent mechanic; he will be much better at it and get the “heavy duty” double sprockett chain set; it will last the life of the car.

Your truck is relatively easy to work on compared to a transversely mounted V6 in a car.

Hope this lets you sleep easier and not worry.

It does help, thank you!

We’re consistent with regular oil changes and service and the engine is still running great, so I’ve no reason to expect an iminent failure, but I had the timing chain break on my '74 Dodge Power Wagon after only 60,000 miles with all the attendant engine damage (bent push rods and valves). Of course that happened on a road trip, putting me at the mercy of an unknown shop far from home. I got treated well and got back on the road quickly, but that’s not an experience I want to repeat.

I know engine design and material has improved over the years, but was looking for second opinions. Thanks for taking the time!

You are allowing the hysteria often displayed by owners of vehicles that use rubber timing belts to poison your mind…Chevy Small Block timing chains are NOT a maintenance item…