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Another thing to remember; if you are new to Subaru remember that if one of your tires needs to be tossed due to damage then you will have to do one of the following; buy ALL new tires or have a tire specialist match the new tire diameter to the ones you have (they do this by removing rubber on the new tire). This has something to do with the AWD system, if the tires are not the same size (or very close) it can ruin your AWD system. (not going to pretend to know how this works but it is a fact).
I am looking for a reference on this as I have a tire to be replaced in a few hours from now - please provide if you have any
 

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found this in manual (3-23) it seems there is AWD warning system in place to warn if there is a mismatch of tires
If the AWD warning light flashes,
promptly park in a safe location then
check whether all four tires are the
same diameter and whether any of
the tires has a puncture or has lost
air pressure for some other reason.
Continuing to drive with the AWD
warning light flashing can lead to
powertrain damage.
 

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I thought it might be a good idea to make a FYI thread regarding tires for our cars (several members have mentioned this). Note that this thread is info that I have stolen from YOU guys and tirerack. If I get anything wrong please don't feel shy to post corrections and I will post them on this first page. I want this first page to be a place where people can find facts regarding sizes they can fit on the Global Platform Imp. In the thread following please post photos of non-stock rims you have bought INCLUDING the size info (thanks).


From Tire Rack, TPMS frequency is 433MHz

Bolt pattern = 5x100, +55 offset.

Wheel nut tightening torque: 89 lbf·ft (120 N·m, 12 kgf·m)*
*: This torque is equivalent to applying approximately 88 to 110 lbf (40 to 50 kgf) at the end of the wheel nut wrench.

Stock sizes:
Premium: 16" 206/55-16 width= 6.5"
Limited: 17" 205/50-17 width = 7"
Sport: 18" 225/40-18 width = 7.5"

Rim and Tire Size Calculator: Rim & Tire Size Calculator. Custom Offsets

Things to remember, the SPORT model has LARGER front brakes (rims and calipers) sport rotor size is 11.6" in diameter compared to every other models 10.9" up front but the rears are all the same at 10.8". People HAVE put smaller rims on the sport and bought larger diameter tires so as not to mess up their speedo readings.

Another thing to remember; if you are new to Subaru remember that if one of your tires needs to be tossed due to damage then you will have to do one of the following; buy ALL new tires or have a tire specialist match the new tire diameter to the ones you have (they do this by removing rubber on the new tire). This has something to do with the AWD system, if the tires are not the same size (or very close) it can ruin your AWD system. (not going to pretend to know how this works but it is a fact).

One of our members put 16" rims on his Sport Model, the clearance is VERY tight to the brake, his comment "Verdict: the 16" wheels I got from Tire Rack (16X7.5 SPORT EDITION P3 ANTHRACITE) fit on the fronts, but with a mere 4.5mm clearance between the caliper and the part of the wheel where the weights are applied."

Can you put rims from older Subies on your new Impreza? Comment from a member: "I just put 205/55/16s on my sport, plenty of brake clearance, handles as expected with snow tires. Steel wheels (16x6.5) w/General Artic Altimax, they were from my 2014 Impreza."

Can you put Crosstrek wheels/tires on my Imp? Comment from a member: "I put 2015 Crosstrek wheels my Sport today The wheels are 17 x 7 and they fit fine."

Rims from a WRX WILL fit our cars unless they are 2015 or newer.

Another great wheel/tire calculator (thanks BuzzBomb). tiresize.com/wheel-offset-calculator

Listen, I am NO mechanic so PLEASE tell me if something needs to be added to this list or if anything is wrong. Thanks. :wink2:
Hello .
I need some help with tire choice.
I got 18x8.5 +35mm wheels
And I dont want to stretch the stock tires on them , my question is will 235/40 r18 tires clear the fender?
Or any other tire suggestions, just want to go as wide as possible without any fender rolling or suspension lift or anything like that , just maximum sizes that will clear under the car .

Thank you .
 

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2019 Subaru Impreza Sport 5 Dr. Manual Shift
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I posted this in 2004 on scoobymods, this was directly from Subaru at the time regarding replacing tires

Tire Wear/Rotation/Replacement/Temporary Spare Tire Operation

We all know that tires wear. There are certain things you, as an owner, can do to help minimize this wear.

1. Keep your tires properly inflated. This is perhaps the single most important thing you can do. Information on correct tire inflation pressure is provided in your owner's manual and on a placard on the driver's door pillar. How often you check your tire inflation is up to you. As a rule of thumb, tires should be checked every time you fill your car with gas. Remember that tires should be checked when cold since tire pressure will increase as the tires warm up.
2. Rotate your tires regularly. SUBARU recommends tires be rotated every 7,500 miles. These are recommended intervals only. Your actual driving conditions may warrant more frequent rotation. Factors such as road surfaces, driving techniques/habits, vehicle loading, and weather, to name just a few, can all have an effect on tire wear.
3. When replacing tires, it is always recommended that you choose tires of the same type, size, construction, and manufacturer as those present on the vehicle as original equipment.

On All-Wheel Drive (AWD) vehicles, it is extremely important that the rolling or outer circumferences of the tires be within 1/4 inch of each other. This means that you must physically measure the size of the tire. This is best done with the weight of the vehicle off the tire and at the tread centerline. Also be certain that the tires are properly inflated since this can affect your readings.

If you need to replace just one tire, the same holds true. The measured difference in circumference between the replacement tire and the other tires on the vehicle cannot exceed 1/4 inch.

Depending on the vehicle mileage, it might be better to replace all four tires.

If the vehicle mileage is low and the tires have been rotated and driven at the proper inflation pressures, then you may be within the allowable 1/4-inch difference in circumference.

If the difference between the new/replacement tire and the current tires is within this 1/4-nch maximum, then the tire should be compatible. If it is not, then other tires will need to be replaced to conform to the 1/4-inch rule.

Exceeding this 1/4-inch difference in tire circumference can place unnecessary wear on drivetrain components, possibly causing them to wear out prematurely.

If your vehicle is AWD (All-Wheel Drive) with an automatic transmission and the temporary spare tire has been installed, put a spare fuse (15 amp) inside the FWD (Front-Wheel Drive) fuse holder (refer to your owner's manual for location). Confirm that the Front-Wheel Drive (FWD) warning light comes on before you drive the car. Installation of this fuse deactivates AWD to prevent possible damage to the drivetrain components that can result due to the use of the smaller temporary spare tire. After re-installing the conventional tire, remove the fuse from the FWD fuse holder to restore AWD operation.

For more information on tires and temporary spare tire usage, always consult your Subaru owner's manual.

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Regarding wheel offset. info that may be of interest, this is not from me, I'm just relaying what someone posted and it seem to be reasonable info.

Hobron from NAISOC answered my question nicely regarding offset:

------------------------------


The simple answer is that the offset should never change despite wheel width. Even a 10" wide wheel will have a +48 offset on your vehicle. It would never fit the car but suspension geometry would be correct if you could bolt it on. I'll explain geometry in a minute. That's where it gets a little more complicated.

Offset is relative to backspacing and wheel width. That's why it's so confusing.

For example, with both wheels having +48mm offsets, the back spacing on a 6.5" wheel is about 5 5/8" while the back spacing on a 7" rim is about 5 7/8". Additionally, a 7.0" wheel with a +42mm offset would have backspacing of about 5 5/8". Note the similarities and remember this for the last paragraph.

Offset is the distance between the centerline of the wheel and the mounting surface of the wheel. Positive offset occurs when the mounting surface is outward of the centerline of the wheel.

Suspension geometry in basic terms is determined by drawing a straight line from the center of the upper ball joint, through the center of the lower ball joint and down to the center of the contact patch of the tire. Since that line is rarely perfectly plumb, the wheel is OFFSET to make the contact patch of the tire sit in the correct position. The offset is determined by some crazy smart engineer with way too much education.

Since offset is calculated using the centerline of the rim, offset will remain the same regardless of wheel width.

One of the reasons problems occur when choosing wheels that are too wide is that backspacing is changing. In the case of high positive offset wheels as are used on most sport compacts, the backspacing increase is noticed more at the inward portion of the wheel. This is evidenced by rubbing on inner fender skirts, the sub-frame, or even on suspension parts in high negative camber applications.

Take some measurements. As long a you have at least 1/4" clearance from the innermost edge of your wheel/tire, you can choose a 7.0" wheel with a +48 offset. The 1/2" added wheel width will be divided equally to the inner and outer edges of the wheel. 1/4" on each side when compared to the stock wheel.

On the other hand, changing to a +42 offset would move the wheel outward 1/4" so the entire 1/2" width change would be noticed only on the outermost edge of the wheel. The result would probably be no clearance issues inside but parts wear "might" be increased.

I hope this helps reduce some of the confusion.

Good luck,
Eric

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23175


Even though this is a number of years old I think it's still valid.
 

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After switching to my winter tires today I notice on the invoice a note saying "Alignment recommended after new tires installed". Do you guys do this after new winter tires are installed on your car?

I have never got an alignment on any of any of my 24 cars. I have had 2 or 3 different sets of wheels and tires on at least 12 of them and never had an issue with uneven wear, pulling to one side, or any other issues. If my steering wheel isn't straight after a pothole, if it's pulling to one side, or if tire wear is uneven I would do it in a heart beat.
 

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I kind of agree with their recommendation that if you get new tires it's good to check the alignment. Tires are a big investment so it's pays to get an alignment checked. It could save on premature tire wear and even MPG's if it's off. Just rotating or swapping wheels over and there isn't any wear, then there is no need.

When I get new tires, I have the alignment checked. I feel better to be safe than sorry. However, if you are diligent and watch for uneven wear and rotate, I don't think you actually need an alignment. To me watching tires includes running your hand over the surface when you rotate them. Sometimes you can feel things like cupping before you see it. We do have some wicked potholes in my area lately, we had a bad winter. My son hit one so bad with the Legacy, I had to replace the wheel and strut. In this case I had to get an alignment because I removed both the front struts. However, with all the pot holes, my guess is it will throw off the alignment eventually. My other son's car, an old Forester, somehow got out of alignment in the rear. He's away from home at college and doing internships pretty far away. I could not keep an eye on the tires. When he came home over break and was going to put the snows on, the all season rears were really worn unevenly. The inside of the rears were down almost to the wear bars. I put the snows on and had the alignment adjusted. It was definitely out looking at the numbers. I'm not sure how that happened but the car has 200K+ miles and he was doing an internship in Colorado.
 

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2019 Subaru Impreza Sport 5 Dr. Manual Shift
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This belongs here :p Tire = Tyre ;)

23216
 
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I see the wheel torque spec has already been added, I'll just add a cut and paste from the owners manual. Also I'm adding a pic of the proper sequence to tighten the lug nuts down. Info regarding lug nuts. You can remove lug nuts with an Impact wrench if you have one. However, you should never install lug nuts with an Impact Wrench unless you are using Torx Stix. Always torque the wheels down with a torque wrench and then check the torque again after driving 100 miles or so.
Don't use any sort of lubrication on the wheel studs, this includes never seize. The torque spec is for dry threads. Adding a lubricant will increase the applied tension. This could eventually snap a stud by stretching it beyond it's elastic point. I know people will argue that they have used never seize for years without an issue, I use to too but the fact remains it's going to increase the tension. It even says in the owners manual to not lube the threads (see attached)

This is how I install and tighten down a wheel. I'm not saying it's the only way, it's just the way I do it and so far have not had an issue. This may seem obvious to some of us but not everyone has done this before.
  • Set wheel on the studs.
  • By hand, start the lug nuts on the threads, this will minimize the risk of cross threading.
  • I like to start at the stud at the highest point, even rotating the wheel so one stud is at 12:00.
    • Don't tighten it all the way just get the threads started.
  • Push on the wheel at the bottom, 6:00 and install the lowest , most diagonal stud to the first one you installed.
    • This makes it so the wheel is now held relatively in place parallel to the hub and it's easier to get the other lug nuts in place. The other studs are now easy to access.
  • Using the sequence shown below, basically a star pattern, install the other bolts in a diagonal pattern.
  • I like to hold the socket (19mm deep) in my hand and using the star pattern, snug down the lug nuts as tight as I can by hand.
  • Verify the wheel is set on the hub, grab the tire with both hands and push hand pull to wiggle it.
    • While not likely, it's possible to have the wheel cocked on the hub slightly, doing this will make sure it's seated properly.
  • Set your torque wrench, set it to the proper torque, in this case 89 ft/lbs (120 N-m)
  • Again using a star pattern, I like to just snug down each bolt till it starts to feel tight but not to the full torque.
  • Go around again, star pattern, this time to the torque setting.
  • Double check and go around a second time at the proper torque.
  • After driving the car re check the torque, yes in a star pattern.
    • I like to keep the torque wrench in the car during my first trip and check when I get where I'm going and when I get home after the car has been sitting long enough for everything to cool down.
I know this seems like a long way to go but it really is easy, sounds like a lot when I list it out though.

One last thing, never use a torque wrench to remove the lug nuts, it's not good for it. Use a breaker bar if you have one or the lug nut wrench supplied with the car.

23221


23222
 

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2019 Subaru Impreza Sport 5 Dr. Manual Shift
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Sport Tire Weight at 8,500 miles on the tires

24512
 

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Went to install a set of these 16" 2005 WRX wheels on the girlfriends 2020 Impreza sedan touring. They don't clear the front caliper.
Listed at 16x6.5" +55.
They just barely rub on a raised dimple on the face of the caliper. I considered grinding that down(I may still do that)

I ordered a 3mm spacer and will give that a go. I can use them on my 86 with extended wheel studs as a backup if they still don't fit.


24535
 

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2019 Subaru Impreza Sport 5 Dr. Manual Shift
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This is what 2011 17" WRX wheels look like on my 2019 Sport. This is my winter setup, I have an aftermarket set of TPMS sensors that I have cloned and they work perfectly. Plenty of clearance n the brakes and with

TPMS sensor info here: Some TPMS info.

Snow Tires 205/50R-17 Firestone Winterforce 2 No change to the accuracy of the speedometer.

The handling has changed rather dramatically. With new tires that have very deep tread depth they feel quite squishy which is to be expected. I'll add how they are in the snow when I get I get to test them out.

24536
 

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This is what 2011 17" WRX wheels look like on my 2019 Sport. This is my winter setup, I have an aftermarket set of TPMS sensors that I have cloned and they work perfectly. Plenty of clearance n the brakes and with

TPMS sensor info here: Some TPMS info.

Snow Tires 205/50R-17 Firestone Winterforce 2 No change to the accuracy of the speedometer.

The handling has changed rather dramatically. With new tires that have very deep tread depth they feel quite squishy which is to be expected. I'll add how they are in the snow when I get I get to test them out.

View attachment 24536
I remember when I went from Michelin Pilot MXX3 summer tires to Blizzaks. The squishy feel takes some getting used to but remember that the rubber needs to be soft and pliable in lower temps which is partly what makes the tires work and is why they are squishy. I didn't change ratios. I just used stock size 225/45/17 which is stock for my 2001 S4. But the Blizzaks were awesome. We are also talking 19 - 20 years ago. I bought another set for my S4 but I never really got to use them. Ended up being money wasted.
 

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Went to install a set of these 16" 2005 WRX wheels on the girlfriends 2020 Impreza sedan touring. They don't clear the front caliper.
Listed at 16x6.5" +55.
They just barely rub on a raised dimple on the face of the caliper. I considered grinding that down(I may still do that)

I ordered a 3mm spacer and will give that a go. I can use them on my 86 with extended wheel studs as a backup if they still don't fit.
Follow up to this. A 3mm spacer fixed the clearance issue up front. I could have probably gotten away with shaving casting lip on the face of the caliper. I didn't want to deal with a rusty caliper come spring on a 2020. I may sort that out in the summer and use higher quality paint like I did on my 86.
24548
24547
 

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Regarding wheel offset. info that may be of interest, this is not from me, I'm just relaying what someone posted and it seem to be reasonable info.



Hobron from NAISOC answered my question nicely regarding offset:

------------------------------


The simple answer is that the offset should never change despite wheel width. Even a 10" wide wheel will have a +48 offset on your vehicle. It would never fit the car but suspension geometry would be correct if you could bolt it on. I'll explain geometry in a minute. That's where it gets a little more complicated.

Offset is relative to backspacing and wheel width. That's why it's so confusing.

For example, with both wheels having +48mm offsets, the back spacing on a 6.5" wheel is about 5 5/8" while the back spacing on a 7" rim is about 5 7/8". Additionally, a 7.0" wheel with a +42mm offset would have backspacing of about 5 5/8". Note the similarities and remember this for the last paragraph.

Offset is the distance between the centerline of the wheel and the mounting surface of the wheel. Positive offset occurs when the mounting surface is outward of the centerline of the wheel.

Suspension geometry in basic terms is determined by drawing a straight line from the center of the upper ball joint, through the center of the lower ball joint and down to the center of the contact patch of the tire. Since that line is rarely perfectly plumb, the wheel is OFFSET to make the contact patch of the tire sit in the correct position. The offset is determined by some crazy smart engineer with way too much education.

Since offset is calculated using the centerline of the rim, offset will remain the same regardless of wheel width.

One of the reasons problems occur when choosing wheels that are too wide is that backspacing is changing. In the case of high positive offset wheels as are used on most sport compacts, the backspacing increase is noticed more at the inward portion of the wheel. This is evidenced by rubbing on inner fender skirts, the sub-frame, or even on suspension parts in high negative camber applications.

Take some measurements. As long a you have at least 1/4" clearance from the innermost edge of your wheel/tire, you can choose a 7.0" wheel with a +48 offset. The 1/2" added wheel width will be divided equally to the inner and outer edges of the wheel. 1/4" on each side when compared to the stock wheel.

On the other hand, changing to a +42 offset would move the wheel outward 1/4" so the entire 1/2" width change would be noticed only on the outermost edge of the wheel. The result would probably be no clearance issues inside but parts wear "might" be increased.

I hope this helps reduce some of the confusion.

Good luck,
Eric

<<<<<<
Great info! Would this damage or cause any issues since it wasn't designed for FWD or is this standard procedure for each time there's a flat?
 
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