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G2
June 20th, 2012, 09:01
I poked around a bit but didn't find anything pertaining to the awful and dark tales of personal experience in the drama of a failed RS6 C5 timing belt.

Don't know the reasons, but apparently the t-belt is high needs compared to other Audi models. Any comments are appreciated if based in fact or knowledge. I've been told the belt was made narrower for the turbo V-8, due to space limitations.

I'm reasearching a RS6 I will likely buy. While it's had plenty done, there is no certain record the t-belt was replaced at 35K (however records show "recommended service" was done, including R&R of the engine and turbo replacement).

Was the 35K belt service covered under Audi warranty? Or was it a customer responsibility? Knowing this would help determine for sure if the work was done.

With that said, the car is near 75K and the current owner has not done the t-belt. Leaving it up to me, which is fine. My main concern is whether there is some actual experience with regards to belt failures. And, if the belt wasn't replaced the first time, how bad did it look when it was replaced (assuming 75K miles or so and 5+ years)-- pre-failure. Any pictures?

Obviously, I'm extrapolating and trying to read between the lines. If the car is bought, it's 1,000 miles to get home. I know what one might say, and am fully aware of those variables and available options. Knowing the others will be of far more use.

I guess the big question is: has anyone with 75K miles or less had a failed timing belt? And: are these engines prone to breaking them (like the 1.8T engine when it first came out, BEFORE the service mileage)?

Thanks much!

Aronis
June 20th, 2012, 19:47
Over time the belt stretches and timing can be off due to slippage.
Mine was off by a good amount at this last change (127000).

I've not seen any mention of frank sudden TB failure.

Tom Sawyer
June 20th, 2012, 20:49
Good question, I've been curious of the same thing since picking up my RS in January. It had 70k on the clock and I knew it was around the corner, but as I did research on the car, I found that the dealer had no record of the 35K TB service (and their records were extensive, each oil change, suspension change, gas tank recall, sway bar etc). Always possible that it just didn't get recorded but also that the car got it's first at 75k. My mechanic said the belt was an average looking used belt, no shredding or damage to speak of. Rollers the same, used but not damaged.

Everyone I've ever talked to including gear heads tend to be pretty shocked at such a short interval and I think the vast majority of us go by the book on it because of the special nature of the power plant.

That probably doesn't help too much because I really don't have any solid proof that my car did not see the 35K service, but all indicators seem to say that it might not have (and it was fine).

And all that said, when 110K rolls around I'll be back in for a TB service. :addict:

4everRS
June 20th, 2012, 20:53
I've never heard of a tbelt breaking on these cars. It can slightly stretch over time. 35k service is paid by Audi. Should have no doubt been done then. Service is every 40k miles. Tbelt is really not even the main cause of possible issues. It's the rollers that wear out. Always replace the bolts with new ones. Ask MaxRS6.

The hunt for a good example can be both fun and frustrating. Good luck.

Tom Sawyer
June 20th, 2012, 23:05
I've never heard of a tbelt breaking on these cars. It can slightly stretch over time. 35k service is paid by Audi. Should have no doubt been done then. Service is every 40k miles. Tbelt is really not even the main cause of possible issues. It's the rollers that wear out. Always replace the bolts with new ones. Ask MaxRS6.

The hunt for a good example can be both fun and frustrating. Good luck.

Completely forgot that the early maintenance costs are covered, it's been a WHILE since I've had an Audi under that coverage. On mine it must have just not been recorded.

So true... have seen some lower mileage units since buying mine that made me wonder if I should have held out longer, but then those can have the same issues too. At the end of the day, it's always a bit of a crap shoot buying a used car, especially these cars, but it's OH so worth it! G/L with the search!

hahnmgh63
June 21st, 2012, 04:28
35K service was covered if it was done in the first 4 years as the warranty was 4yrs/50,000 miles. Some dealers did the service at just under the 4yr mark for some owners even though they hadn't reached the 35K mark yet. The timing belt is the exact same on the other 40Valve 4.2 V8's so why it has to be done in half the interval, who knows? Gates racing does have a belt they say is 600% stronger for a piece of mind but I wouldn't push it too far as their have been a couple of roller failures and a stud failure on the list here. Although most of those other parts are also the same as on the 40V 4.2 so they normally are intended to last longer. I did go with the Gates Racing belt myself.

kismetcapitan
June 21st, 2012, 06:03
I'd agree - rollers and the studs they're mounted on are the concern. It's easy to make a long life belt, but bearings and the studs that hold them can weaken. I had a stud failure on my Skyline, and it was not a good experience. Fortunately, my engine builder covered it, but it required a complete set of new valves and valve guides...and that was getting off lucky.

While kevlar-reinforced timing belts are unbreakable, what I'd REALLY like to see are roller studs made by someone like ARP.

And as we all know, TB replacement is only a pain because of access issues. Swapping TBs and rollers on some cars can be done DIY in an hour.

hahnmgh63
June 21st, 2012, 15:24
When I replaced my belt I did use the stronger Gates Belt, at least I'd have a piece of mind that it wouldn't be the failure point. I also replaced all of the studs & bolts since there was a failure of a stud on the list a few years ago. Normally I would think the rollers & bearings should last 70K plus since they are the same ones used on the normally aspirated 40V motors and I just don't see where the RS6 puts more of a strain on them although I'll still do mine every 35K or so but I would be worried if I was 5~10K past due, I would just do it or get it scheduled.

G2
July 4th, 2012, 05:23
[QUOTE=hahnmgh63;235742]35K service was covered if it was done in the first 4 years as the warranty was 4yrs/50,000 miles. Gates racing does have a belt they say is 600% stronger for a piece of mind /QUOTE]

I read thru the manual and it states that required service is not covered under warranty. I'd think the dealers would be on top of pushing for the service, however.

Judging from the looks of my car' t-belt, feel confident it was previously changed. I've seen many timing belts over the years and by 75K and 9yrs, are usually a bit cracked and dry looking. The small upper idler pulleys are probably suspect due to the age. Seems Audi should have made them a bit bigger, even if there's little to no tension on them.

I purchased the Gates Racing belt and all t-belt related items, including cam and crank seals. I will tackle the job in the near future, once other service items are attended to. I changed the rear and center diff. fluids to Amsoil 85-140 for extra protection. Will use 85-110 on the front diff (has cooling ducts). Anything comparable on the road uses 85-140 and for my climate feel it's appropriate. Whereas the OE 75-90 fluid under 500+hp/tq doesn't.

I was more than a little concerned about the timing belt, but thanks to all the input and a easy visual inspection, put myself at ease (somewhat).