Staggered 20" rims vs. all 4 the same? Spacers?

[motorinamini]

I currently have the Staggered OEM 20" style 168 wheel set-up for my '04 X5 4.4i w/ sport package. They are mounted with the OE Michelin Diamaris (which have great handling, but are loud and don't last long) and I am not getting very good gas mileage (ave. 18) w/ mostly highway driving AND it is just about time to get new tires.

I am looking into taking off the staggered rears, putting ones like the fronts back there so that all of the wheels/tires are the same, so that I can rotate them. I would like to mount the wheels with Michelin Tour HP All-seasons from tirerack.com.

So my questions are:
1) Is this a good idea? (considering I will probably get better gas mileage and that front tires cost less than rear tires)
2) Will I need spacers for the back wheels if I eliminate the "stagger"? (because the off sets are different)

[anerbe]

1. it's not a bad idea, especially from the economy standpoint (cheaper tires). you should get better gas mileage, but i would think it won't be greater than 1mpg. i was planning on getting a square 20" setup, as I already have 4 - 275/20's available.

2. to maintain the same handling characteristics, you should stagger the wheels, although i'm sure you'll be fine without. the non-sport 3.0 and 4.4 come with non staggered wheels. as long as it fits in the front, it should fit in the back. only thing you may miss from non-staggered would be the rear stance, but you could fix it with spacers.

[bigfish]

I have been running 20"x10.5" wheels with 315/35/20 Pirelli Zero Rossi's on all the way around for 3 the past years on 4.6is and love it! Longer tire life, better wear in my opinion.

bf

[X5Kiwi]

I am also considering this, as the 315/35R20 tyres are almost twice the price of the 275/40R20 tyres that I am running on the front, and also there are no suitable 315 tyres in New Zealand at the moment, with the middle of August being the earliest avaliable from one supplier.

Since I already have very good 275/40R20 tyres on the front, but almost dead 315/35R20 on the rear, I might go for 275/40R20 all round, and then when they are all ready to replace, go for something bigger maybe 295/40R20 all round. And gaining the ability to rotate tyres front to rear will be an added bonus.

Is anyone else running same size all round? Any comments?

[Weasel]

Originally Posted by X5Kiwi

I am also considering this, as the 315/35R20 tyres are almost twice the price of the 275/40R20 tyres that I am running on the front, and also there are no suitable 315 tyres in New Zealand at the moment, with the middle of August being the earliest avaliable from one supplier.

Since I already have very good 275/40R20 tyres on the front, but almost dead 315/35R20 on the rear, I might go for 275/40R20 all round, and then when they are all ready to replace, go for something bigger maybe 295/40R20 all round. And gaining the ability to rotate tyres front to rear will be an added bonus.

Is anyone else running same size all round? Any comments?

If you want to put the 275/40r20 tires in the back to match the fronts you would need to get the same width rims as the fronts to put them on. And I'd stay away from the 295/40r20s as they are a different rolling diameter than the 275/40s and the 315/35s and would cause stress to the drivetrain as the 03 and earlier have regular transfer cases...

[X5Kiwi]

How could having 4x 295/40r20 tyres on cause stress to the drivetrain? Sureley having 4 identical tyres it the best way to NOT stress the drive train.

[Weasel]

Originally Posted by X5Kiwi

How could having 4x 295/40r20 tyres on cause stress to the drivetrain? Sureley having 4 identical tyres it the best way to NOT stress the drive train.

4 of the same is perfect... I meant having 275/40 in the front and 295/40 in the rears would be a recipe for disaster. The only drawback of having 295/40R20's would be the speedometer off a little bit, but that is livable as long as you know about it.

[TwinsPoppa]

Originally Posted by motorinamini

I am looking into taking off the staggered rears, putting ones like the fronts back there so that all of the wheels/tires are the same, so that I can rotate them. I would like to mount the wheels with Michelin Tour HP All-seasons from tirerack.com.

So my questions are:
1) Is this a good idea? (considering I will probably get better gas mileage and that front tires cost less than rear tires)

Yes and no. IMO depends on your priority. Nothing inherently wrong with what you are suggesting but you do have to factor in the cost of buying 2 wheels. I guess factoring in the cost savings on buying smaller width tires and being able to rotate them offsets the wheel costs.

2) Will I need spacers for the back wheels if I eliminate the "stagger"? (because the off sets are different)

No not necessarily. The spacers would give it a better look but might lead to premature wheel bearing failure . However, I don't think the 15mm difference is going to make that much of a difference on the suspension geometry to require spacers.

See above. Good Luck!

[bigfish]

Many of us have run same size tires & wheels front and rear for many years with no problems. Twinspopa is exactly right the additional cost of wider tires is offset by getting longer life and greater mileage out of each tire do to the ability to rotate. X5Kiwi, can't you just order tires from someone outside New Zealand and have them shipped to you? I order my tires through tirerack.com they have a very good selection. On my X I have run the Michelin 4x4 Diamaris, Continental 4x4 Sportcontact, Dunlop SP Sportmaxx & Pirelli PZero Roso. I found the Dunlop's and the Pirelli's to be superior, with my favorite being the Pirrelli PZero Rosso.

I have included a link to the tirerack.com page with additional info on the tires I have run. Compare Tire Search Results

bf

[J.Belknap]

Just an FYI for those looking into different sizes but keeping the same rolling diameter front to rear.

Tire size calculator
Wheel Offset Calculator
Tire Size Calculator - tire & wheel plus sizing
http://www.rims-n-tires.com/info_spe...20/%20Comparer