why do vw still use cambelts instead of chains?

[wjwren]

Most newish diesel engines are now chain driven. Why do VW/Audi still use cambelts?

[JimboSmith]

Mainly, because they're cheaper.

[cuprabob]

They seem to be using chains in most of the new petrol engines. Not sure why this hasn't migrated over to the diesel variants.

Edited by cuprabob on Sunday 3rd February 22:45

[xreyuk]

In an effort to make them a bit quieter?

How long will a chain last?

[22rgt B Squadron]

Cambelts are quieter. Some chains will last the life of an engine some wont and on many requires a large part of the engine stripped down for replacement and in general costs twice if not many times more for a chain,sprockets,guides, gaskets/seals and tensioner job .

[cuprabob]

Chains are supposed to last the life of the engine although VW has had issues with them snapping and the tensioners playing up.

The cambelts on the latest CR engines are 140k miles but VW UK puts an age of 4 years on them, probably to keep revenues up.

[DukeDickson]

cuprabob said:

Chains are supposed to last the life of the engine although VW has had issues with them snapping and the tensioners playing up.

The cambelts on the latest CR engines are 140k miles but VW UK puts an age of 4 years on them, probably to keep revenues up.

Sounds like a revenue generator to me - up at over 6 years and counting personally. Do rattlers put more stress on a belt than their smooth & suave equivalents?


Cambelt lives seem to be going up & up - I thought 125k on my heap was decent (and suspect by that age/mileage, you could consider taking a flyer and not replacing).

[xreyuk]

I was told one of the other reasons was because VW didn't think the chain would outlive the rest of the engine before it snaps. So if you keep changing the cambelt you can keep going on that engine.

[Caulkhead]

I've owned lots of engines with chains, so far never had a failure whereas I've had two cambelts go before the required change mileage. One of the cam chains in a V8 I owned is on 264,000 miles and still counting. . . . . . .

[wheedler]

Caulkhead said:

I've owned lots of engines with chains, so far never had a failure whereas I've had two cambelts go before the required change mileage. One of the cam chains in a V8 I owned is on 264,000 miles and still counting. . . . . . .

My friends 40k 2008 golf r32 has tensioner loose, that will be 1500 to fix at a good indy, where as my gtd had its wTerpump and cambelt changed at 80k for 400 at vw dealer.

Really don't think ones better than the other

[MG CHRIS]

Caulkhead said:

I've owned lots of engines with chains, so far never had a failure whereas I've had two cambelts go before the required change mileage. One of the cam chains in a V8 I owned is on 264,000 miles and still counting. . . . . . .

The only downside of chains are the owners. Chain tensioners and chains require good oil to remain lubricated if you don't carry out oil changes regulary then the tensioner can become slack and the chain jumps happens a lot on the 3 cylinder corsa engines. Also if say a headgasket goes on a chain driven engine is a lot more complex compared to a belt driven engine.

[davepoth]

MG CHRIS said:

The only downside of chains are the owners. Chain tensioners and chains require good oil to remain lubricated if you don't carry out oil changes regulary then the tensioner can become slack and the chain jumps happens a lot on the 3 cylinder corsa engines. Also if say a headgasket goes on a chain driven engine is a lot more complex compared to a belt driven engine.

It's not much harder to do a HG on a chain driven car. Just pop the tension off and there's enough slack in the chain to get it off the cogs, only takes a minute. The chain jumping a tooth is a pretty good failure mode really - it's not enough to make Mr. Valve meet Mr. Piston but it does make the car run like a bag of crap so the owner will take it to a garage. Given the choice it'd be chain every time.