I currently have run flat tires. I want to switch to steel belted radials for a smoother ride. Will I have to change rims as well to match new tires???

P designates a tire for a passenger car, 225 is the width of the tire in mm, 75 is the ratio of sidewall height to the width (eg thesidewalls are 225*0.75=168.75 mm tall), R is the type of tire (radial), and 16 is the diameter of the tire in inches. Customizing the tires gives you different performance results.

If you want your car to act according to how the manufacturer specified, go back to the stock tires. However, your current tires have a larger diameter than the stock, which means your rims are also larger than stock; you would probably have to replace the rims as well, which can be expensive.

I would stick with your new sizes. Different sized tires will not harm your vehicle in any way. I would also recommend going to a store that offers lifetime warranties like Les Schwab; they are invested in insuring that that everything is fitting correctly so they don't have to refund you anything.

check if you tires have rayon cords or steel belts. this is a problem associated with the older tyres that had rayon cords as the main structure of the tyre. When left standing after running and allowed to cool the rayon belts actually took on a flat spot on the bottom and the noise lasted until the tyre warmed up enough for the tyre pressure to make the tyre round again. In extreme cold it may be the same for steel belted radials as the flat bottom of the tyre would hold the shape until the rubber warmed up .

yes as long as the rim is a 15 inch rim what matters is the diameter not the width of the rim however you want to match the size of you tires as closely as possible as it will cause abnormal wear on your tires, brakes , and traction control to name a few if you cant match all four at least make sure to match the two in the front and try to keep smaller tires to the front and larger tires to the back

My first thought is bad front tires...I presume they are radials...you can have them checked for what is called "radial runout"...the cause is usually a defective belt or belt seperation...your symptom matches this problem...if you are unsure about the tires in a visual inspection...you can switch front tire wheels from right to left to see how this affects your steering...the seperated belt tire is caused by chuck-holes and sometimes poor construction quality...The pulling can start as low as 30 mph...and gets worse as you drive faster...Hope this helps.

Sound like out of balance tire or a separated tire or bearing but, the two most common causes are the ones. I suggest visit some tire shop and would like to have the tires inspected and balanced.

Some customers may comment on shaking/vibration in the steering wheel, floor or seat while driving at highway speeds (typically between 60-72 mph (96-115 km/h)) on smooth roads.

These specific vehicles may be sensitive to various rotating mass assemblies, especially if they are considered to be out-of-balance.

In order to correct this:
1. Visually inspect the tires and the wheels. Inspect for evidence of the following conditions and correct as necessary.
- Missing balance weights
- Bent rim flange
- Irregular tire wear
- Incomplete bead seating
- Tire irregularities
- Mud/ice build-up in wheel
- Stones in the tire tread

2. Set the tire pressure to 30 psi (205 kpa) COLD.

3. If the road test indicates a shake/vibration still exists, check the imbalance of each tire/wheel assembly on a known, calibrated, off-car dynamic balancer. If any assembly calls for more than 1/4 ounce on either rim flange, remove all balance weights and rebalance to as close to zero as possible.

Important: Some GM dealers may have a Hunter GSP9700 Road Force Balancer. This will simplify Step 5 by not requiring dial indicators. If a Hunter GSP9700 machine is available, it may also be used to measure the radial force of the tire/wheel assembly. A guideline here is 18 lbs or less.

4. While on the balancer, measure wheel runout. If radial or lateral runout exceeds .020 in (0.50 mm) for aluminum wheels (.030 in (0.76 mm) for steel wheels), replace the wheel.

5. After confirming wheel balance and wheel runout, if any changes were made, road test the vehicle again.

6. If the smooth road shake/vibration still exists:
Important: The completed worksheet must be attached to the hard copy of the repair order.

Record Radial Force Variation readings if you have access to Hunter GSP9700 Wheel Balance equipment. Use the worksheet shown in this bulletin to record the readings.

If one or more of the tires have RFV readings in excess of 18 lbs, match mount the tires to get below 18 lbs. Readings of 12 lbs. or less are preferable for critical customer concerns.

If the RFV can not be reduced to an acceptable level, replace the affected tire with one obtained locally.

The screened tire program is no longer in effect for Bridgestone/Firestone, Goodyear and Michelin. Low speed screened tires are available from Continental General only, and only for the Buick LeSabre.

Road test the vehicle to ensure the shake/vibration has been resolved.

7. Replace both lower control arms on vehicles built prior to the VIN breakpoints shown. The new lower control arms may provide an incremental improvement to the vehicle ride. Customers who have become "tuned in" to the shake condition may still feel some shake in the vehicle after the new lower control arms are installed.
Refer to Lower Control Arm Replacement, (refer to the Parts Information table below for SI document ID numbers).

Important: THE CONTROL ARMS SHOULD ONLY BE INSTALLED ON VEHICLES IF, AFTER THE TIRE AND WHEEL DIAGNOSIS AND REPAIRS HAVE BEEN PERFORMED, THE VIBRATION CONDITION STILL EXISTS.

Hope this helps; also keep in mind that your feedback is important and I'll appreciate your time and consideration if you leave some testimonial comment about this answer.

Thank you for using Fixya, and have a nice weekend.

What you have is a very common and annoying problem with aluminum wheels. There are 3 things you can do. Take it to a tire shop and have them put rubber sealant around the bead, put fix a flat in each tire, or like you said, buy steel wheels.

mcdevito75 here, Your Tire Mechanic could be right regarding the chrome wheels leaking a bit of air, however, you have radial tires, either all season or steel belted, and once punctured radial tires are very hard to seal, very hard. I would advise a new tire rather than all 4 new chrome rims.

You have a warp in one of the steel belts inside your tire. Sorry but there is no fix for this except replacement. It is strongly advised that you replace "both" front or rear tires as a pair for they have been in service the same amount of time and will surly do the same thing down the road a bit. Thank you, Dana P.S. It is to your best advantage to change these tires asap for this can progress to a very dangerous situation very quickly.

The sidewall of a tire is very thin and for safety reasons should not be repaired. The tread part is thick and contains the steel belt. If you put a plug in the tread section, the steel belt will hold the plyg in place. Once the sidewall is damaged, change the tire.

Spare tireSpare tireYou might find that some tire dealers will give you a trade in value for the new donut spare.