2.0 TDi Vs 3.0 TDi Engine for mpg?

The 3.0tdi engine is smoother, more powerful and generally more refined. The MPG is lower because it's higher capacity.

If economy is your primary aim, go for the 2.0tdi. If you want power and refinement get the 3.0tdi.

The 2.7 is a good middle ground in terms of MPG, however you will incur all of the additional running costs (apart from MPG) of the 3.0tdi, without the additional power. They are also quite rare.

I haven't owned a 2.0tdi so can't offer a direct comparison, but the audi V6 TDIs are great engines. Cam chain replacement is costly, however from what I understand this is not a massively common fault. See recent posts about the 3.0tdi on the B7 forum.

All in all, it depends what you want. The 2.0tdi gets high 50's mpg if you drive it right, the 3.0tdi will only get mid-40's at best so if you do a lot of miles it's going to cost you... IMO the additional cost is worth is, hence I have a 3.0tdi. From what I understand the 2.7 can achieve high 40's if driven correctly, but I'm not 100% on that. Running costs are comparable until something goes wrong, which is dependent on many things: service history, driving style, mileage and luck.

There is never a clear-cut answer to these kinds of questions, only you know your priorities and your financial ability to foot the repair bill if something major comes up... but Audis can be expensive for repairs regardless...

desertstorm said:

In the B8 shape the 2.7 comes with FWD and a multitronic auto box. So not the one to go for if you want performance.

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This is the same for the B7, however I wouldn't say that you should avoid it due to performance concerns. The delivery of the power may not be aggressive, but for road driving (rather than track) most of the time this is actually beneficial.

desertstorm said:

Things like servicing cost more as the engine uses about 7.5L of oil for a service, air and oil filters are no more expensive.

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He's right on the oil, there's a huge capacity on the V6's! Although the air filter is the same across the B6 and B7 range.

desertstorm said:

The older 3.0 V6 TDI B6 had issues with cam chains that have hopefully been sorted.

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The B6 was only available in a 2.5tdi, the B7 however... but there are similar issues regarding cam chains on several forums from people posting about A5's (for example) about the same problem with the 3.0tdi, oddly with newer and lower mileage cars??

We went from a 2.0 (140bhp) to a 3.0 (233bhp) and I had the same concerns. Had ours nearly 2 years and hand on heart i'd sy the MPG differences are minimal.

I know the OBD is to taken with a pinch of salt. but we get about 450-480 miles to a full tank. Mine is a manual so I cant comment on the auto. Cant see us going back to a 2.0 the 3.0 is very addictive and the novelty has not worn off.

Have the manual 2.0tdi 170 quattro, i ignore the dis and calculate tank to tank and I'm lucky to see 42mpg doing 40 mile motorway/ main road commute each way 70-75max! Should have got a 3.0...

I didn't realise the MPG on the 2.0tdi was so poor!

Mr-C, I know I have a smaller tank being a cab (7 litres less) but I see between 350 and 380 miles per tank, that's with a mix of driving. You must be very careful right your right foot to see that kind of MPG from the 3.0tdi...

jjmurphy21187 said:

I didn't realise the MPG on the 2.0tdi was so poor!
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Neither did I! Coming from a big old A6 2.5tdi quattro (not V6) that never went below 43mpg and regularly saw 50-52.. I'm a bit disappointed.......
Hopefully removal of a certain egr and dpf along with a decent remap might improve things for the 2.0 engine mpg...

I would agree, so far haven't spent much more on fuel when I moved from a 2.0 TDI FWD to a 233bhp 3.0V6 TDI AWD

Mr-C said:

We went from a 2.0 (140bhp) to a 3.0 (233bhp) and I had the same concerns. Had ours nearly 2 years and hand on heart i'd sy the MPG differences are minimal.

I know the OBD is to taken with a pinch of salt. but we get about 450-480 miles to a full tank. Mine is a manual so I cant comment on the auto. Cant see us going back to a 2.0 the 3.0 is very addictive and the novelty has not worn off.

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