# Most reliable motor??



## QUIK16V (Aug 15, 2010)

Which motor is the most reliable for the A6??? The 3.0, the 2.7t, or the 4.2???


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## frankinstyn (Oct 11, 2004)

The 2.8 liter. The 3.0 is probably just as reliable but it can be very difficult to work on. The 4.2 is also incredibly reliable but it is factory paired with a weak transmission so that reliability is kinda ruined. 

The 2.7t CAN be reliable with proper maintenance. That all said it isn't as reliable as the 4.2 or the 2.8.


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## PPGOAL (Apr 22, 2009)

The "only" thing unreliable about the 2.7T is the turbos -- they take more care and precautions than a non-turbo engine. If the turbos pop, they can be very expensive. But so are 4.2 transmissions. I have 178k on my A6 and know of another driver with almost 190k, both stock.


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## rs4-380 (Dec 12, 2000)

reliability wise the 2.8 and the 4.2 are about the same. 2.8 is easier to work on, more common, and parts are cheaper.


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## A2Everyday (Jun 4, 2007)

Love my 2.8.. 176K on her.. just slow as balls


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## A4dream (Apr 14, 2009)

I too love my 2.8... yea shes slow a molassas but its solid as a horse and it has 145,000 miles on her now and never a issue. But I am SERIOUSLY concidering a 4.2L w/ 6spd swap inteh near future.


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## frankinstyn (Oct 11, 2004)

I too have the 2.8 and I'm not disappointed by the speed of it I just would appreciate more. I'm considering the supercharger kit. Probably mid-next year. 145k as well.


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## monkeytronic (Oct 5, 2009)

frankinstyn said:


> The 2.8 liter. The 3.0 is probably just as reliable but it can be very difficult to work on. The 4.2 is also incredibly reliable but it is factory paired with a weak transmission so that reliability is kinda ruined.
> 
> The 2.7t CAN be reliable with proper maintenance. That all said it isn't as reliable as the 4.2 or the 2.8.


Just for grins, the C5 4.2, S6 and RS6 get the ZF 5HP24A transaxle which actually has a higher torque capacity than the ZF 5HP19FLA that the AWD C5 2.8, 3.0 and 2.7T get.

Of course, all of the V8 C5s naturally do produce more torque in stock form than any of the V6 C5s so "weak" is a bit subjective a term to use.

Purported issues of reliability aside, C5 4.2s on the used market are, more often than not, better equipped than the typical V6 C5 (most amusingly, understated features like the standard power adjustable steering column with memory and optional solar sunroof were V8-only), sport a most wholesome V8 soundtrack and, of course, widebody good looks. :thumbup:


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