Cheap tire issue on '93 NA

1993MR2NA · 07-07-2009, 07:25 PM

I had a rear blowout and was out of town and had to quickly replace both rear tires. The only tires they could get in over the weekend were Kumho 225/50r15 91H.
After this replacement, my car feels very dangerous on the freeway. It sways back and forth like the rear end wants to break loose. Is this because of weak sidewalls?

What really has me confused is that the tires that came off of it were only a 90S rating, which is less than the 91H that is on there now. Is there really that big of a difference in brand name over rating?

Any help is greatly appreciated,
Jerry

Rex · 07-07-2009, 10:41 PM

Check the tire pressure in all of your tires and set to spec. Make sure you have the proper size tires all around. In other words make sure they put 2 of the same size on the back.

Did they do an alignment when you got the tires installed perhaps they messed something up. Ask for them to recheck it. You might have to say the car pulls to get them to put it back on the rack. BTW Does it pull?

Did you hit something when the tire blew? perhaps you damaged a suspension component. Either jack up the car and check or go to a place like sears and get a free evaluation.

You might be able to get the tires warrantied out. Most manufactures have "ride complaint" warranties you might have to call Kumho direct and ask them what to do.

streetrack 3vz ht · 07-07-2009, 11:13 PM

after you wear the tires a little the 'squirm' will be reduced

next time buy a max performance summer tyre and you will be more happy

ebouwman · 07-07-2009, 11:13 PM

ya that sounds pretty sketchy

palos · 07-07-2009, 11:43 PM

Presuming you had the same rated tires front and rear, the "S" rated tires that were replaced with "H" rated tires would, if anything, induce oversteer, having a stiffer sidewall. It would be helpful to know the make and model of the front and rear tires. BTW, S are rated to 108 mph and H are rated to 130 mph, not an ideal situation, but under the circumstances you and the tire store most likely were under, there weren't many options -- finding a used 195/55-15 or 225/50-15 would have been most difficult.

If the car feels unstable, I would presume that your alignment was effected, probably causing a toe out scenario in the rear. This would cause the car's rear end to follow any ripples, curvatures, etc… in the road. Going in a straight line, the difference in tire speed and load ratings would be negligible to non existent.

Aside from checking the before mentioned air pressure, also check the torque on the wheels. They should be in the 80-85 pound range.

1993MR2NA · 07-08-2009, 12:49 AM

Thanks for the replies.
I do have some other issues I'm working on, but only expected new rear tires to help and not make things worse.

• Car pulls to the right (more noticable after new rear tires)
• I just discovered that the front tires are 195/60's instead of factory 195/55's
• I have some play in my rear lower ball joints. (new ones will be here any day now)

So I guess I'll see how it feels after replacing the rear ball joints and then getting an alignment. One other thing. The old tires wore way too soon on the inside and you can even see the tires tilted when you look at it from the rear. Is this tilt normal or should that get a camber adjustment when I have the 4-wheel alignment done?

Thanks again,
Jerry

palos · 07-08-2009, 02:02 AM

Inside edge wear can be caused by toe-out, and/or excessive negative camber. Alignment specifications are relative, i.e. if the specs call for 1/8th toe in, and you are at 1/16th toe in -- relatively you are toed out from the specs. Until your lower ball joints are replaced, the alignment could cause wandering based on the play caused by the ball joints. That may be the reason for the pulling issues. Your negative camber may be reduced after the new ball joints.

If your tires were worn on the inside edge, new tires with an even wear pattern, can change the handling of the car, for better or worse.

The improperly sized front tires should be replaced. Hopefully, Kumho makes the appropriately size (and speed rated) model to fit the front.

1993MR2NA · 07-08-2009, 03:52 AM

Thanks all! I'll post back after my changes.

Since nobody mentioned it, I'm guessing that there are no major problems with the Kumho brand? I was thinking about replacing all the tires with V rated ones. I have seen 'BFGoodrich g-Force Sport' and 'Falken Ziex ZE912' V rated in the 2 sizes I need. Any recommendations on which brand to go with?

Jerry

p.s. No laughing at putting V rated tires on a N/A please :-)

TomsMR2 · 07-08-2009, 06:24 AM

i like sumitomo tires. ive ran a ton of them and tbeyre tbe best cheap tires around.. ive even hammered them on the track and beat many cars. i have a set of HTR+'s on right now, and they never let me down. they dont have a good max summer performance tire, i wont run those either, and thats a whole different rant

kumhos suck.. every kumho ive used has let me down. they make good racing tires and thats about it. the MX is supposed to be decent, but for the price you can run better tires.. so again, suckage.

beyond that.. you have a ton of issues. fix all your issues, get aligned, and see how the car handles after that. especially with suspension and handling concerns, you MUST fix everything you know is broken before diagnosing anything. the next step after that is checking every component for proper operation and no play. once thats inline you have to align it.. 95% of the time that fixes everything. genuine tire problems are uncommon.

1993MR2NA · 07-09-2009, 10:23 PM

Just a quick update. After replacing the rear lower ball joints (and rotors/pads), the dangerous sway I was feeling has gone away! So I'm back to terrorizing the neighborhood again while I wait for the correctly sized front tires to arrive. I decided to put Kumho's on the front so they will match the Kumho's already on the rear. But they don't make a 195/55 AST, so I had to go with the ASX.

Just thought of another question though. The owners manual states tire pressures for the front and rear tires. Shouldn't we always use the pressures listed on the tire? They can vary quite a bit from tire to tire.

Thanks again everyone for all the great info,
Jerry

TomsMR2 · 07-10-2009, 04:46 AM

if you have stock wheels, you should use the pressures listed for the vehicle.

no tire has recommended pressures listed on them. they have max pressure only. you should never run max pressure.

1993MR2NA · 07-11-2009, 02:53 AM

I learn something new every day. I always put a few pounds less than max, but usually never less than 4 under. So your saying that even though my rear tires say 52psi max pressure that I should only put the owner manual recommendation of 33psi in them?

TomsMR2 · 07-11-2009, 03:44 AM

yup! absolutely. i think the pressure recommendation is like 29f 33 rear. 40psi is too much pressure, if you have 48 in there now your tires are grossly over inflated.

i put 35psi in all my cars no matter what though. i havent found a car yet that 35psi doesnt work perfectly in (not trucks, not commerical vehicles, etc etc).

07-07-2009, 07:25 PM	#1 (permalink)
1993MR2NA Natural Aspiration Skills Join Date: Apr 2009 Posts: 46 Thanks: 2 Thanked 0 Times in 0 Posts iTrader Rating: (0/0% )	Cheap tire issue on '93 NA I had a rear blowout and was out of town and had to quickly replace both rear tires. The only tires they could get in over the weekend were Kumho 225/50r15 91H. After this replacement, my car feels very dangerous on the freeway. It sways back and forth like the rear end wants to break loose. Is this because of weak sidewalls? What really has me confused is that the tires that came off of it were only a 90S rating, which is less than the 91H that is on there now. Is there really that big of a difference in brand name over rating? Any help is greatly appreciated, Jerry

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07-07-2009, 10:41 PM	#2 (permalink)
Rex No Skills Join Date: Jun 2009 Posts: 13 Thanks: 0 Thanked 1 Time in 1 Post iTrader Rating: (0/0% )	Check the tire pressure in all of your tires and set to spec. Make sure you have the proper size tires all around. In other words make sure they put 2 of the same size on the back. Did they do an alignment when you got the tires installed perhaps they messed something up. Ask for them to recheck it. You might have to say the car pulls to get them to put it back on the rack. BTW Does it pull? Did you hit something when the tire blew? perhaps you damaged a suspension component. Either jack up the car and check or go to a place like sears and get a free evaluation. You might be able to get the tires warrantied out. Most manufactures have "ride complaint" warranties you might have to call Kumho direct and ask them what to do.

07-07-2009, 11:13 PM	#3 (permalink)
streetrack 3vz ht retired from e stock 3/09 Join Date: Apr 2009 Location: los angeles Posts: 85 Thanks: 0 Thanked 2 Times in 2 Posts iTrader Rating: (2/100% )	after you wear the tires a little the 'squirm' will be reduced next time buy a max performance summer tyre and you will be more happy

07-07-2009, 11:13 PM	#4 (permalink)
ebouwman Curve Hugger Join Date: Jan 2009 Location: BC, Canada Posts: 1,390 Thanks: 18 Thanked 48 Times in 48 Posts My Google Map iTrader Rating: (0/0% )	ya that sounds pretty sketchy

07-07-2009, 11:43 PM	#5 (permalink)
palos … Join Date: Apr 2009 Posts: 170 Thanks: 0 Thanked 20 Times in 18 Posts iTrader Rating: (0/0% )	Presuming you had the same rated tires front and rear, the "S" rated tires that were replaced with "H" rated tires would, if anything, induce oversteer, having a stiffer sidewall. It would be helpful to know the make and model of the front and rear tires. BTW, S are rated to 108 mph and H are rated to 130 mph, not an ideal situation, but under the circumstances you and the tire store most likely were under, there weren't many options -- finding a used 195/55-15 or 225/50-15 would have been most difficult. If the car feels unstable, I would presume that your alignment was effected, probably causing a toe out scenario in the rear. This would cause the car's rear end to follow any ripples, curvatures, etc… in the road. Going in a straight line, the difference in tire speed and load ratings would be negligible to non existent. Aside from checking the before mentioned air pressure, also check the torque on the wheels. They should be in the 80-85 pound range.

07-08-2009, 12:49 AM	#6 (permalink)
1993MR2NA Natural Aspiration Skills Join Date: Apr 2009 Posts: 46 Thanks: 2 Thanked 0 Times in 0 Posts iTrader Rating: (0/0% )	Thanks for the replies. I do have some other issues I'm working on, but only expected new rear tires to help and not make things worse. • Car pulls to the right (more noticable after new rear tires) • I just discovered that the front tires are 195/60's instead of factory 195/55's • I have some play in my rear lower ball joints. (new ones will be here any day now) So I guess I'll see how it feels after replacing the rear ball joints and then getting an alignment. One other thing. The old tires wore way too soon on the inside and you can even see the tires tilted when you look at it from the rear. Is this tilt normal or should that get a camber adjustment when I have the 4-wheel alignment done? Thanks again, Jerry

07-08-2009, 02:02 AM	#7 (permalink)
palos … Join Date: Apr 2009 Posts: 170 Thanks: 0 Thanked 20 Times in 18 Posts iTrader Rating: (0/0% )	Inside edge wear can be caused by toe-out, and/or excessive negative camber. Alignment specifications are relative, i.e. if the specs call for 1/8th toe in, and you are at 1/16th toe in -- relatively you are toed out from the specs. Until your lower ball joints are replaced, the alignment could cause wandering based on the play caused by the ball joints. That may be the reason for the pulling issues. Your negative camber may be reduced after the new ball joints. If your tires were worn on the inside edge, new tires with an even wear pattern, can change the handling of the car, for better or worse. The improperly sized front tires should be replaced. Hopefully, Kumho makes the appropriately size (and speed rated) model to fit the front.

07-08-2009, 03:52 AM	#8 (permalink)
1993MR2NA Natural Aspiration Skills Join Date: Apr 2009 Posts: 46 Thanks: 2 Thanked 0 Times in 0 Posts iTrader Rating: (0/0% )	Thanks all! I'll post back after my changes. Since nobody mentioned it, I'm guessing that there are no major problems with the Kumho brand? I was thinking about replacing all the tires with V rated ones. I have seen 'BFGoodrich g-Force Sport' and 'Falken Ziex ZE912' V rated in the 2 sizes I need. Any recommendations on which brand to go with? Jerry p.s. No laughing at putting V rated tires on a N/A please :-)

07-08-2009, 06:24 AM	#9 (permalink)
TomsMR2 Formerly Tom Brokaw Join Date: Feb 2005 Location: Bay Area Posts: 2,497 Thanks: 8 Thanked 233 Times in 168 Posts Blog Entries: 1 iTrader Rating: (0/0% )	i like sumitomo tires. ive ran a ton of them and tbeyre tbe best cheap tires around.. ive even hammered them on the track and beat many cars. i have a set of HTR+'s on right now, and they never let me down. they dont have a good max summer performance tire, i wont run those either, and thats a whole different rant kumhos suck.. every kumho ive used has let me down. they make good racing tires and thats about it. the MX is supposed to be decent, but for the price you can run better tires.. so again, suckage. beyond that.. you have a ton of issues. fix all your issues, get aligned, and see how the car handles after that. especially with suspension and handling concerns, you MUST fix everything you know is broken before diagnosing anything. the next step after that is checking every component for proper operation and no play. once thats inline you have to align it.. 95% of the time that fixes everything. genuine tire problems are uncommon.

07-09-2009, 10:23 PM	#10 (permalink)
1993MR2NA Natural Aspiration Skills Join Date: Apr 2009 Posts: 46 Thanks: 2 Thanked 0 Times in 0 Posts iTrader Rating: (0/0% )	Just a quick update. After replacing the rear lower ball joints (and rotors/pads), the dangerous sway I was feeling has gone away! So I'm back to terrorizing the neighborhood again while I wait for the correctly sized front tires to arrive. I decided to put Kumho's on the front so they will match the Kumho's already on the rear. But they don't make a 195/55 AST, so I had to go with the ASX. Just thought of another question though. The owners manual states tire pressures for the front and rear tires. Shouldn't we always use the pressures listed on the tire? They can vary quite a bit from tire to tire. Thanks again everyone for all the great info, Jerry

07-10-2009, 04:46 AM	#11 (permalink)
TomsMR2 Formerly Tom Brokaw Join Date: Feb 2005 Location: Bay Area Posts: 2,497 Thanks: 8 Thanked 233 Times in 168 Posts Blog Entries: 1 iTrader Rating: (0/0% )	if you have stock wheels, you should use the pressures listed for the vehicle. no tire has recommended pressures listed on them. they have max pressure only. you should never run max pressure.

07-11-2009, 02:53 AM	#12 (permalink)
1993MR2NA Natural Aspiration Skills Join Date: Apr 2009 Posts: 46 Thanks: 2 Thanked 0 Times in 0 Posts iTrader Rating: (0/0% )	I learn something new every day. I always put a few pounds less than max, but usually never less than 4 under. So your saying that even though my rear tires say 52psi max pressure that I should only put the owner manual recommendation of 33psi in them?

07-11-2009, 03:44 AM	#13 (permalink)
TomsMR2 Formerly Tom Brokaw Join Date: Feb 2005 Location: Bay Area Posts: 2,497 Thanks: 8 Thanked 233 Times in 168 Posts Blog Entries: 1 iTrader Rating: (0/0% )	yup! absolutely. i think the pressure recommendation is like 29f 33 rear. 40psi is too much pressure, if you have 48 in there now your tires are grossly over inflated. i put 35psi in all my cars no matter what though. i havent found a car yet that 35psi doesnt work perfectly in (not trucks, not commerical vehicles, etc etc).