# Question about buying new tires **URL:** \ **Category:** Maintenance/Repairs\ **Tags:** matrix, toyota\ **Created:** [October 2, 2009, 11:04pm UTC](https://community.cartalk.com/t/question-about-buying-new-tires/37466 "2009-10-02T23:04:18Z")\ **Posts on this page:** 19\ **Page:** 2
**Author:** ![megatron1000](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/megatron1000/32/1458_2.png) [@megatron1000](https://community.cartalk.com/u/megatron1000)\ **Post date:** [October 3, 2009, 6:04pm UTC](https://community.cartalk.com/t/question-about-buying-new-tires/37466/21 "2009-10-03T18:04:18Z")
245/50R16 has a 1" taller sidewall than a low-profile 215/45R17 and 1" smaller rim. the comparison is between two very dissimilar tires, except for the 245mm width. ---
**Author:** ![CapriRacer](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/capriracer/32/22_2.png) [@CapriRacer](https://community.cartalk.com/u/CapriRacer)\ **Post date:** [October 4, 2009, 1:08pm UTC](https://community.cartalk.com/t/question-about-buying-new-tires/37466/22 "2009-10-04T13:08:44Z")
Unfortunately, the TRA Yearbook is only published in hardcopy ($50) and is not allowed to be published in any other form. The Tire and Rim Association is a standards organization and its only source of income is the sale of these books and related stuff. (Note: I just looked up the price of the yearbook and it’s now $80!) However, you can get hints of what the yearbook says by looking at what the tire manufacturers list as rim width ranges - and other things. Most tire manufactuer’s web sites will give you a rim width range for a given tire size. But you can also find the info at on-line tire retailers such as Tire Rack. ---
**Author:** ![DoctorPinto](https://avatars.discourse-cdn.com/v4/letter/d/b19c9b/32.png) [@DoctorPinto](https://community.cartalk.com/u/DoctorPinto)\ **Post date:** [October 4, 2009, 2:21pm UTC](https://community.cartalk.com/t/question-about-buying-new-tires/37466/23 "2009-10-04T14:21:17Z")
I’m a big fan of keeping the tires and rims stock. I bet you will be too after you do this! By the way, did the new tires screw up your speedometer accuracy? That’s another can of worms you might have opened. ---
**Author:** ![JoeMario](https://avatars.discourse-cdn.com/v4/letter/j/3bc359/32.png) [@JoeMario](https://community.cartalk.com/u/JoeMario)\ **Post date:** [October 4, 2009, 2:23pm UTC](https://community.cartalk.com/t/question-about-buying-new-tires/37466/24 "2009-10-04T14:23:20Z")
Megatron1000: Why do I get the sense that you’re discounting the valuable input you’re getting in these replies? I have played around with tire sizes in my day. Sometimes it worked fine. Other times it was a big mistake. Based on the knowledge of those who gave you replies, and the tire size mistakes I’ve made, I’d listen carefully to the input carefully that you asked for. ---
**Author:** ![mshugna](https://avatars.discourse-cdn.com/v4/letter/m/ce73a5/32.png) [@mshugna](https://community.cartalk.com/u/mshugna)\ **Post date:** [October 4, 2009, 3:12pm UTC](https://community.cartalk.com/t/question-about-buying-new-tires/37466/25 "2009-10-04T15:12:46Z")
All this to make a matrix look fancier…I don’t get it…where in South Florida…hope you don’t loose control of the car in traffic. ---
**Author:** ![Caddyman](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/caddyman/32/23_2.png) [@Caddyman](https://community.cartalk.com/u/Caddyman)\ **Post date:** [October 4, 2009, 4:21pm UTC](https://community.cartalk.com/t/question-about-buying-new-tires/37466/26 "2009-10-04T16:21:29Z")
That depends on who is looking… ---
**Author:** ![megatron1000](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/megatron1000/32/1458_2.png) [@megatron1000](https://community.cartalk.com/u/megatron1000)\ **Post date:** [October 4, 2009, 4:21pm UTC](https://community.cartalk.com/t/question-about-buying-new-tires/37466/27 "2009-10-04T16:21:47Z")
so you cannot cite your above post im afraid i cannot take it at face value. ---
**Author:** ![JoeMario](https://avatars.discourse-cdn.com/v4/letter/j/3bc359/32.png) [@JoeMario](https://community.cartalk.com/u/JoeMario)\ **Post date:** [October 4, 2009, 4:55pm UTC](https://community.cartalk.com/t/question-about-buying-new-tires/37466/28 "2009-10-04T16:55:53Z")
Megatron1000 wrote: > so you cannot cite your above post im afraid i cannot take it at face value. CapriRacer has worked in the tire industry designing and developing tires for many years. He’s a huge wealth of respected knowledge with anything related to tires and handling. Talk about biting the hand that feeds you. ---
**Author:** ![jtsanders](https://avatars.discourse-cdn.com/v4/letter/j/c2a13f/32.png) [@jtsanders](https://community.cartalk.com/u/jtsanders)\ **Post date:** [October 4, 2009, 10:29pm UTC](https://community.cartalk.com/t/question-about-buying-new-tires/37466/29 "2009-10-04T22:29:01Z")
I’ll second that. CapriRacer gave you the only professional advice thus far. You should take it seriously. And he did tell you exactly how you can find the book as well as other useful sources of the information you seek. If all you want is confirmation of your choice, why bother posting at all? But if you want want an honest, informed opinion, CapriRacer gave you one. ---
**Author:** ![megatron1000](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/megatron1000/32/1458_2.png) [@megatron1000](https://community.cartalk.com/u/megatron1000)\ **Post date:** [October 5, 2009, 12:55am UTC](https://community.cartalk.com/t/question-about-buying-new-tires/37466/30 "2009-10-05T00:55:30Z")
I took the advice seriously. I made my decision after hearing all the pros and cons. Thanks for the advice, opinions and suggestions. thanks a lot. ---
**Author:** ![megatron1000](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/megatron1000/32/1458_2.png) [@megatron1000](https://community.cartalk.com/u/megatron1000)\ **Post date:** [October 5, 2009, 12:56am UTC](https://community.cartalk.com/t/question-about-buying-new-tires/37466/31 "2009-10-05T00:56:17Z")
i agree with you. a taller sidewall will not improve the looks imo. ---
**Author:** ![megatron1000](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/megatron1000/32/1458_2.png) [@megatron1000](https://community.cartalk.com/u/megatron1000)\ **Post date:** [October 5, 2009, 12:58am UTC](https://community.cartalk.com/t/question-about-buying-new-tires/37466/32 "2009-10-05T00:58:50Z")
no they did not screw up the speedometer accuracy. the diameter difference between the 215/45 and 245/40 is .41% ---
**Author:** ![megatron1000](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/megatron1000/32/1458_2.png) [@megatron1000](https://community.cartalk.com/u/megatron1000)\ **Post date:** [October 5, 2009, 12:59am UTC](https://community.cartalk.com/t/question-about-buying-new-tires/37466/33 "2009-10-05T00:59:35Z")
I have not discounted any of the valuable input. i thank everyone for the input. i have learned things i did not know before. ---
**Author:** ![megatron1000](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/megatron1000/32/1458_2.png) [@megatron1000](https://community.cartalk.com/u/megatron1000)\ **Post date:** [October 5, 2009, 1:01am UTC](https://community.cartalk.com/t/question-about-buying-new-tires/37466/34 "2009-10-05T01:01:20Z")
yes it looks really nice. i can tell people hang back before passing me just to look at the trucklet riding on wide 245’s. ---
**Author:** ![CapriRacer](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/capriracer/32/22_2.png) [@CapriRacer](https://community.cartalk.com/u/CapriRacer)\ **Post date:** [October 5, 2009, 1:02am UTC](https://community.cartalk.com/t/question-about-buying-new-tires/37466/35 "2009-10-05T01:02:09Z")
Thanks for the vote of confidence, guys. I will point out that all you need to do to confirm that a 245/40R17 doesn’t fit on a 7.5" rim is to go to the Tire Rack web site and look up what is availble in that tire size. You’ll get a long list of tires available. I just did that and got a list of 68 tires. If you click on the pot that says “Specs”, you’ll get a list of all the tires available for that type of tire, with the tire size in question at the top. One of the columns is “Rim Width Range”. Here’s one - a BFG g-Force T/A KD: [http://www.tirerack.com/tires/Spec.jsp?make=BFGoodrich&model=g-Force%20T/A%20KD&partnum=44YR7GFTAKDL&vehicleSearch=false&fromCompare1=yes](http://www.tirerack.com/tires/Spec.jsp?make=BFGoodrich&model=g-Force%20T/A%20KD&partnum=44YR7GFTAKDL&vehicleSearch=false&fromCompare1=yes) According to that, the rim width range is 8" to 9.5", just what Tire and Rim says. But if you don’t believe that, go to a tire manufacturer’s web sites and look the tire size up yourself. I am modifiying this post since, as I was typing it, the OP posted back. Hopefully, he won’t put on the 245’s. It sure would be an expensive way to find out I was right about the instability! ---
**Author:** ![megatron1000](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/megatron1000/32/1458_2.png) [@megatron1000](https://community.cartalk.com/u/megatron1000)\ **Post date:** [October 5, 2009, 1:08am UTC](https://community.cartalk.com/t/question-about-buying-new-tires/37466/36 "2009-10-05T01:08:24Z")
CapriRacer: thanks for the advice. i looked at tirerack website extensively before making my purchase. i played around with tire sizes and recommended tires. check out also: [http://www.1010tires.com/tiresizecalculator.asp](http://www.1010tires.com/tiresizecalculator.asp) for a really accurate and user-friendly tire size calculator tool. I understand the manufacturer recommends the 8" rim but at the end of the day: -im only stretching .5" on each side of the rim. -i paid $85 per tire mounted balanced and installed. -got the look i wanted. i know i did an unconventional installation, and i came here asking for advice on whether this would affect my vehicle catastrophically and after a page or two of replies i think it is safe to say most of the damage that will occur to the rims/tires/auto is going to be long-term and over a long period of time, not while i am commuting to work in slow surface streets. so far the tires are working out awesome. the car feels like a tank on the road and the alignment is perfectly straight. like i said in a post above, people dig the look, and so do i. ---
**Author:** ![CapriRacer](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/capriracer/32/22_2.png) [@CapriRacer](https://community.cartalk.com/u/CapriRacer)\ **Post date:** [October 5, 2009, 11:16am UTC](https://community.cartalk.com/t/question-about-buying-new-tires/37466/37 "2009-10-05T11:16:01Z")
Just so we are clear: The spec rim width for a 245/40R17 is 8.5", and the allowable rim width variation is -0.5", +1.0". So using a 7.5" is SHRINKING the tire 1.0" - outside the tolerance by 0.5". If you don’t percieve any problems - Great! But there is a possibility that you will get some stability issues as well as some wear issues. Nevertheless, good luck. ---
**Author:** ![megatron1000](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/megatron1000/32/1458_2.png) [@megatron1000](https://community.cartalk.com/u/megatron1000)\ **Post date:** [October 5, 2009, 9:43pm UTC](https://community.cartalk.com/t/question-about-buying-new-tires/37466/38 "2009-10-05T21:43:18Z")
I did not know of CapriRacer’s vast and respected knowledge. The ‘hand that feeds you’ line works out better when someone is actually giving you a tangible good or $$, not some guy working for a company somewhere. there’s no relation between him being the hand that feeds me and my choice of tires. LOL! ---
**Author:** ![pleasedodgevan2](https://avatars.discourse-cdn.com/v4/letter/p/ad7895/32.png) [@pleasedodgevan2](https://community.cartalk.com/u/pleasedodgevan2)\ **Post date:** [October 6, 2009, 5:39am UTC](https://community.cartalk.com/t/question-about-buying-new-tires/37466/39 "2009-10-06T05:39:26Z")
For that little bit of fun, I wouldn’t bother. You seem to have a mind for details, so I will try to make you a rich person. Make a five year plan for your personal financial goals. The main question to ask yourself is “Where do I want to be financially in five years”. You can do that sometime in the next five days. You need new tires. If your present tires are worn out; your only worry will be whether or not the new tires will scrape the car when you want to steer. The tires won’t hurt the five year plan if they fit. If your present tires are still good, your plan takes a hit. [Previous page](https://community.cartalk.com/t/question-about-buying-new-tires/37466.md?page=1)