Zaphodb17

I know this has probably been covered, but what is the replacement interval for the 2.8L 30-valve cam belt? The owner's manual says 120,000 or so, but I found a sticker on the underside of the hood which says 75k. Anyone know?

4Driver4

I like 75k.

Zaphodb17

I'm planning on keeping the car and will be doing the the cam belt hokey-pokey soon. I was just curious about the big discrepancy between the factory manual and what looks like a knee-jerk reaction that may have taken place after the 30-vs were in production for awhile. I was unsure what the official Audi position was. I'd imagine it's 75K.

4Driver4

Here's the thing, if you know you are keeping the car to 150k, do the belt at 75k. If you are keeping the car to 120k, then maybe it makes sense to mitigate the risk a bit and do it at 60k. If you are planning on keeping the car to 160k, maybe it's worth stretching a bit to ever 80k. If you are running the car to 90k, maybe you want to skip the servive altogether.

As I say, it depends on the overall "life" of the car, your tolerance for risk, and the cost of the timing belt.

Our last service was at 175k. We'll probably keep the car to about 260k. We will not be doing another belt service.

S4_Cinci (I S'edTFA)

the factory specified service interval) is to make the ownership cost look better in the consumer guide magazines - they look at costs up to 100k. AoA set the 105k interval, NOT the engineers who designed and built the engine. I waited until 100k and the belt looked great. The real issue is with the tensioner, idler pulley, and water pump which are all driven by the TB. If one of these go out, it will take the TB down with it.

Most people who drive the car relatively hard will opt to do the change in the underhood sticker mileage ballpark. It's all odds; many people have had belts last well past 100k and some have had issues with bad pulleys or water pump before 60k.

MAKE SURE that when you do replace it, you replace all the other components that are touched/driven by the TB. I've know too many people who simply had the belt changed and 10k miles later it goes out and they blame the belt, but it was from the other stuff that didn't get replaced. Don't forget the thermostat as well, since it is behind the TB and costs way too much $ in labor to replace if it fails.

FixedWing

which is dropping all of the time as the resale values drop and as more of them are ending up in junk yards.

The big problem I have is that when you buy a car with an unknown history and you are told that the belt has been changed, has it been changed at 75K or at 105K? If the former and you try to run it to 105K then you could actually end up going to 135K on the belt. If you are really conservative then you need to change at 150K even though the belt might only have 45K on it at that point.

My guess is that most belts will have been changed shortly after 105K. Few cars with unknown history are really in the hands of enthusists.

Stephen

4Driver4

Agreed with all but the 105k common number. I think most dealers try to sell it sooner.

77'911

<center><img src="http://i14.tinypic.com/82sjodz.jpg"></center><p>I did ours at 58k, and the waterpump bearings were starting to make noise at that point. Was quite glad I did it. The belt could have probably gone a bit longer but frankly I don't have much faith in the rest of the system(tensioner, rollers, etc.). In the pic are some of the factory tools to do the job.

FixedWing

Doing work is how they make their money, after all.

But I don't think that the AoA dealers do. They want to sell new cars. They achieve that by convincing their customers that their cars don't need money spending on them.

And I think most cars will spend their life with the AoA dealer until the timing belt gets done.

Stephen

FixedWing

I need to start keeping my eye open for these tools. :-)

Stephen