2013 BMW 5 Series Touring SE 520d - Wheel alignment and fuel consumption - SP59

I've just had a full new set of tyres fitted to my 2013 BMW 5 Series Touring at 29,000 miles, the garage also did a wheel alignment check, and some adjustment was made to the toe on all 4 wheels. My fuel consumption has now increased from around 53-54 mpg to consistently under 50. The new tyres fitted were exactly the same as the originals (Pirelli Cinturato P7s). The garage has rechecked the alignment and says everything is okay, but the fuel consumption has not improved. No other servicing has been performed. Could re alignment have such an effect?

Thanks

2013 BMW 5 Series Touring SE 520d - Wheel alignment and fuel consumption - RobJP

More likely to be tyre pressure related.

If your new tyres are at the correct pressure, then it is likely that your old tyres were running on high pressures (less rubber in contact with the road) which gave better fuel economy.

Or if the previous (incorrect) alignment meant less tyre in contact with the road, then that would have the same effect.

I'm a little surprised at all 4 tyres needing to be changed. On my 325d the backs were changed at 27,000 miles, the fronts still having about 5mm remaining at that time (now on 34k miles).

2013 BMW 5 Series Touring SE 520d - Wheel alignment and fuel consumption - Peter.N.

If the alignment was sufficiently out to affect the fuel consumption you would be getting noticable wear on the tyres, particularly on one edge.

2013 BMW 5 Series Touring SE 520d - Wheel alignment and fuel consumption - SP59

Thanks for all the comments

Tyre pressures are consistent, the first thing I checked!

I dont' think the old aligment could have been that far out... less tyre in contact with the road...as they hadn't worn too unevenly and the fuel consumption had been the same since the car was new. I know that as I do the same journey every day.

Probably could have got another 3-4000 out of the fronts, but there wasn't that much left on them, so had the lot changed.

Suspect next step will be to get another garage to check

2013 BMW 5 Series Touring SE 520d - Wheel alignment and fuel consumption - craig-pd130

Although the new tyres are Pirelli P7 etc and therefore superficially identical, I think they do different versions of those (i.e. P7 'Blue') which may give different characteristics.

I wonder if that's the case here?

2013 BMW 5 Series Touring SE 520d - Wheel alignment and fuel consumption - quizman

If my car's tyres are wearing evenly I would not let anyone fiddle around with the tracking. I've never had a tracking job done properly yet, after they have messed around the steering wheel is off centre and the tyres start to wear unevenly.

If you took your car to have your tracking done at 5 tyre places, the readings would all be different.

Leave well alone!

P.S. How do you get such a good fuel economy on your 520? I can't get your figures on mine.

Edited by quizman on 05/05/2016 at 18:18