Changing lights in pairs?

[sebhaque]

As the old saying goes, you always get 3 problems at once etc etc.

While at home this weekend my old man asked me to change one of the sidelights on his car as it had fused. He also mentioned that he noticed as I was reversing into the driveway that one of my BMW's numberplate illumination lights had gone out - and this morning when I went to check on the VX I noticed it had a brake light out too. Typical.

My question is - I've heard it's better to change lights in pairs. How far should I go with this? I'm guessing the brake lights and sidelights are a must, but should I change the numberplate lights as a pair too?

Also, does having overinflated tyres help with MPG? I'm giving the cars a once-over this afternoon and seeing as my 120d gets 59.4mpg on a motorway, it'd be nice if I could bang in 2-3 extra PSI and get that up to 60mpg.

TIA for any replies.

[Rich_W]

Only worth it if getting to 1 bulb is a pain. Example. On some cars, you have to remove the whole headlight to change a bulb. As you've got it out, you may as well fit the other bulbs. If it's no grief, I wouldn't bother personally.

[Lanby]

DO NOT over inflate your tyres, they will wear out in the centre a lot quicker and cost you more in new rubber than you save in fuel!

[Ozzie Osmond]

sebhaque said:

does having overinflated tyres help with MPG?

Yes, but it's a completely daft thing to do. Over-inflated tyres have much less grip than properly inflated tyres (because the tread doesn't sit flat on the road) so your brakes won't work as they should. Your tyres will also wear out more quickly because the centre of the tread bulges out and the sides of the tread aren't running on the road. Very bad idea!

[Taita]

Unless its a ballache to change the bulb, there is no point whatsoever in changing working bulbs.

Sometimes you can take the 'preventative fawning' a bit far on this forum. (not you personally)

[dowahdiddyman]

Why must you change the brake or sidelights as a pair if only one has blown? Just because one has blown it don`t always follow that the other will shortly.

[sebhaque]

Cheers guys . Looks like it's single lights and standard 30/32 psi for me.

[Engineer1]

Changing headlamp bulbs as a pair may make sense if you are uprating as one bright bulb and one original may give a stty light pattern that means you are wasting the expense of uprating one bulb.

[HellDiver]

I've found headlight bulbs often blow within days of each other, so now always change those in pairs. Other bulbs, only do them when they pop.

[philmots]

I've changed headlight bulbs in pairs as normally i buy a better brand/better performing bulb than what i guess will be in there.

Any others, don't bother.

[lescombes]

HellDiver said:

I've found headlight bulbs often blow within days of each other, so now always change those in pairs. Other bulbs, only do them when they pop.

Done that for years and my pals now do....as same happens...change one..the other pops.....

[David87]

I always change everything in pairs - if one goes, the other will be close behind it usually.