[neilmc]

Hi,just wondering what everyone is using tyre pressure wise on a 3 series with 18" wheels. Is there an optimum pressure front/back? that gives best results/wear. Answers in psi please, for god sake not bar!

[M3-FAST]

Hi Neil - I have mine running as per the sticker on the inside sill visible when you open the drivers door - they run very high (40psi+) and seem to lose about 10psi every couple of months

My electric compressor starts to struggle past 40psi tho lol - defo makes a difference (I did mine last weekend) to the feel of the car.

[neilmc]

Thanks for the quick reply.Just checked them and it is 38 rear/34 front.Will look at adjuting them when it has done a few 100 miles to see if there is any difference.

Will also be posting up my thoughts on the car compared to my old B7 Audi A4 2.0T quattro. Looking quite good so far!

[jjbirch]

35ish for the front and 36-37 at the back 18's seems to run fine

[Carrera RSR]

Keep an eye on the pressures. My steering went strange before a service was due. Dealer bollocked my like a 3 year old for not checking pressures every week!!! they ended up at 17psi and trashed the front outer edges. Still got 40,000 miles out of the rears and 44,000 out of the fronts!!! Will be investing in a digital tyre guage for the new arrival.

[jjbirch]

wow 40 on the fronts ....on my car done 20k on the fronts lol and 17 on the back

[medrep]

38 rear 36 front for me, when I can be bothered to check them. Does make a positive difference when they are inflated correctly though.

On the subject of tyre wear, my dad has a 535M with non rft's 19's and has gone through x3 sets of rears in under 12 months!!

The wear with mine has been superb on these bridgestones. My last e46 with michelin ps2's would only do 15k max on the rear!! The grip was far far better though than my current tyres.....

[neilmc]

3 sets in 12 months-excellent,good man!

Nearly always check pressures daily out of routine-overkill I know, but better safe than sorry. Have a digital guage from Halfords, very handy.

[Carrera RSR]

Originally Posted by jjbirch

wow 40 on the fronts ....on my car done 20k on the fronts lol and 17 on the back

I honestly kid you not. I do 'drive' the car well but predominantly on the motorway. However at 45,500 miles the car was written off!!

[BC4J]

Just did mine tonight - 41 front / 39 back.

[TK - 421]

Originally Posted by carrerarsr

However at 45,500 miles the car was written off!!

Wasn't due to bald tyres i hope

[gIzzE]

2.6 bar front and 2.9 bar on the rear. Don't know what psi that is?

I always take the pressures for the car fully loaded and drop .2 bar from each.

[andy69]

Originally Posted by carrerarsr

Keep an eye on the pressures. My steering went strange before a service was due. Dealer bollocked my like a 3 year old for not checking pressures every week!!! they ended up at 17psi and trashed the front outer edges. Still got 40,000 miles out of the rears and 44,000 out of the fronts!!! Will be investing in a digital tyre guage for the new arrival.

My 18" RFT's are 2.2bar (32psi) front and 2.5bar (36psi) rear as per the door sticker. The rear's are still in good shape after 50,000kms (31,000 miles) but the fronts are worn on the outside edge
So I dont know if the fronts should be a little higher or not. Anyone else run these tyres at these pressures and noticed the same wear ?

[andy69]

Originally Posted by BC4J

Just did mine tonight - 41 front / 39 back.

Do you need them that high because of all the options you chose ?

[BC4J]

Originally Posted by gIzzE

... Don't know what psi that is?

You're taking the psi now!

[BC4J]

Originally Posted by andy69

Do you need them that high because of all the options you chose ?

[Ant Man]

On my E46, inside driver's door (in psi) recommends: 42 rear and 34 front. I check pressures one a month and sometimes they have dropped by 1psi, other times no drop. Wear is even across all the tyres and still have a lot of depth left with 13,000 miles on them. My driving is mostly a mixture of A and fast B roads (twisties to have fun) with a little town driving.

[ShereKhan]

I usually leave them at full load front and back (as per door sticker)

The rears lasted 35k miles and I still have the original fronts with 49k miles.
The front's still have 4mm on.

[PhilR]

Just checked my RFT's

Must admit it's been about 10 weeks since I last checked.

Fronts were both 2.2 bar (31psi)
Rears were both 2.4 bar (35psi)

I have inflated them to 2.6 (38psi) front and 2.9 (42psi) back. That was what they were 10 weeks ago. So the pressures have dropped about 20%Seems a lot to me?

Trouble is with RFT you cannot see if they are underinflated.

The pressures of 42psi seem high for a car tyre. That was until I checked my MTB tyres and they need between 45 and 60 psi For the record got these set at 50psi - comfort in mind

My fuel consumption has dropped about 1 to 2 mpg over same period too (in the car I might add - not on the MTB). I'll have to see if it picks up again over the next few weeks I'm guessing the low tyre pressures will have effected this.

PhilR

[gIzzE]

Originally Posted by BC4J

Just did mine tonight - 41 front / 39 back.

Huh??

Why more on the front?? Never known any BMW to need that?

[BC4J]

Originally Posted by gIzzE

Huh??

Why more on the front?? Never known any BMW to need that?

Mine does 'cause it's 'Individual'

[gIzzE]

Originally Posted by BC4J

Mine does 'cause it's 'Individual'