BMW 520d vs 520i engines

[Slackman99]

Looking for a comfortable new cruiser and am considering a 5 series (ideally a touring).

I do a fair few miles a year, circa 20-25k mainly constituting long runs. My head says that the diesel is the right choice, but I'm concerned about issues with timing chain stretch and the general move away from diesel in the industry.

I'd be looking at 4 years old, around 40k miles and used approved, so should have a full service history.

Is the B47 diesel reliable or does it still have issues with snapping/stretching timing chains?

Is the B48 petrol more reliable than the diesel and any common issues to be aware of.

Realistically what mpg could I expect from the 520i on 'a run'. Would 50mpg be realistic sat at 70mph or is that miles away from what's achievable.

Alternative could be a Mercedes with the 2ltr OM654 diesel. I'm not aware of any major common faults with these, but an E class seems to command a premium over the 5 series.

[Gweeds]

For that mileage it would be diesel all day long for me. The 20i is a little underpowered for that size of car IMO and you'll have to wring it's neck more without the torque of the diesel.

[Slackman99]

Ok, fair point and probably what my head is suggesting.

So then BMW B47 - is the camchain still and issue?

Mercedes OM654 - is this a reliable engine

Volvo VEA - not seen any reports of common faults one the EGR recall has been done?

[Xenoous]

B47 is fine. N47 had the issues. We have it in X3. Perfectly fine in that, will be good enough in the 5 series.

[Harbuzi]

Slackman99 said:

Looking for a comfortable new cruiser and am considering a 5 series (ideally a touring).

I do a fair few miles a year, circa 20-25k mainly constituting long runs. My head says that the diesel is the right choice, but I'm concerned about issues with timing chain stretch and the general move away from diesel in the industry.

I'd be looking at 4 years old, around 40k miles and used approved, so should have a full service history.

Is the B47 diesel reliable or does it still have issues with snapping/stretching timing chains?

Is the B48 petrol more reliable than the diesel and any common issues to be aware of.

Realistically what mpg could I expect from the 520i on 'a run'. Would 50mpg be realistic sat at 70mph or is that miles away from what's achievable.

Alternative could be a Mercedes with the 2ltr OM654 diesel. I'm not aware of any major common faults with these, but an E class seems to command a premium over the 5 series.

I have a G30 520i. Never seen 50mpg on the board! Have had it for a little over two years now and covered 24k miles in that time. Average probably sitting just under 40mpg - mid 40s possible if very well behaved on a run.

Certainly don't find it lacking any oomph when required, but for 25k miles a year the diesel is probably the better bet!

In terms of reliability it's been flawless, but the manufacturer warranty runs out this month, so let's see!

[Slackman99]

Sounds like I was probably right to consider the diesel as the front runner still.

I'll be considering the BMW extended warranty, but it seems to be fairly expensive and almost twice the price of the equivalent Mercedes version!

[Slackman99]

Also thanks for the information on the 520i mpg. That is kind of what I thought it might be but wondered if it was like the 1.5tsi VAG engines where they are actually ok on a run

[Wagonwheel555]

The modern 2.0T BMW engines are far more economical than previous versions but lets face it, its not going to give the same MPG as a diesel equivalent.

With that mileage, I would suggest a diesel as it would be worth the cost savings.

If you were doing 10-12k, I would get the petrol.

[Harbuzi]

Slackman99 said:

Sounds like I was probably right to consider the diesel as the front runner still.

I'll be considering the BMW extended warranty, but it seems to be fairly expensive and almost twice the price of the equivalent Mercedes version!

Just renewed mine. £73p/m with a £250 excess for the fully comp with breakdown! Sigh!!