Tire Wear, Problems, Alignment

[cmartin248]

Not only is the short tire life very expensive, its wasteful, and sends 4 tires to the landfill every 10k miles. I bought the 2003 SC430 with 130k miles on it and it had run-flat tires with less than 10K on them and they were worn out. The wear is only on the inside edge as most of you know and was about equal on all four tires. My first idea was to get the alignment fixed, but after taking it to a guy who is really good with alignment, it was dead on for the factory settings. My next move was to buy non run-flats and get the 30-40k that some people on here were bragging about. The new set of bridgestones didn't do any better and got around 10k before they gave up. Now is was time to do some measuring. I used simple tools like levels, eye site, and a home made toe-in guage. The first thing I notice was a lot of negative camber. Next, was a little toe-out on both the front and rear wheels. I jacked the rear end up and removed both wheels. Took all the negative camber out that I could, and put just a slight toe-in (1/16"). Moved to the front wheels and because they didn't have as much factory negative camber, I only moved the camber about 4 clicks in the positive direction. Then I brought the toe-in to about 1/16" also. I still feel the rear wheels have too much negative camber, but the only way I get more positive is to modify the swing arms. The front camber is about where I want it. A lot of you will want to know how much camber, but I only used a bubble level and I don't have anyway to measure it. I talked to the Lexus dealer and he said nobody was getting more than 10-12k on the run-flats. It seems if you are one of the lucky people getting good mileage on your tires, then your camber is not set factory. Lexus puts tons of negative camber on the car to improve the handling under extreme driving conditions. If you are like me and drive normal without doing the teenager drifting thing, then talk to your alignment guy and have him set your car up for your type driving. He can't alter the factory specs unless you approve it. I waited to write this until I had 5k on my new tires and they appear to be wearing very evenly and no sign of inside wear. Drop me a line if I can help....

[TomWoodLexus]

I know this may be a dead post, but I was searching for stuff on google and came across it. The reason the SC cars get bad tire wear is Neg. camber.... usually. You can also have other angles out, but there is alot of Neg. Reason being is that it greatly improves cornering stability. And when Lexus thought of doing that, it is to make them be able to say "this car can do the slalom 2 seconds faster than car X" So bring out the rear camber from -0.2 to -.05 and you will be fine.

Also, make front right camber more negative than left front camber. Just a bit...

[TomWoodLexus]

oh yeah... usually people who can afford the SC don't care about replacing tires often, because they like to race around in them.. and if they can afford the car, they can surely get the tires!

[cmartin248]

In reply to reducing the rear camber from -.2 to -.05, the adjustment will not allow reaching -.05. I intend to modify the swing arm so that I can bring it to -.02. I'm still getting some inside wear on the rear. Why should the RF camber be more negative than the LF???? I have them both as near 0 camber as the adjustment will allow. Your second post says that people who can afford this car, don't mind spending $1200 every 10k miles for tires. I certainly can afford this car, but can't stand the waste. Why would anyone buy a 4 seat car (of which the rear seat is useless, except for a couple of grocery bags) to drive on a slalom course? The car has fair power and good handling, but by no means matches a Corvette, Porsche or even a Ducati 999. My 2003 SC430 has 155,000 miles on it and I have done all the maintenance myself, including a new timing belt at 130k. The car is very dependable and there have been no problems at all mechanically.

[farmergirl]

oh yeah... usually people who can afford the SC don't care about replacing tires often, because they like to race around in them.. and if they can afford the car, they can surely get the tires!

Hi Cmartin248,

Seems you have much experience with getting your tires just right. I'm a new owner of an 02 sc430 and am making notes about what tires to replace my runflats (Michelin Pilot Sports) when it's time and now I want to make note of exactly what to tell the tire guy to do when he mounts them regarding the alignment. Can you send the exact specs that work best to extend the life of new tires to their maximum? Thank you!

[TomWoodLexus]

Wow, I can't believe I made it back into the SC forum! By chance you have posted today and I checked today!

Anyways, the thing with wide tires and low profiles is that when the front tires turn, the sidewalls don't flex any. Bigger ratio tires flex to the side a little and this attributes to a major part of a tires wear, and shoulder wear big time. So city driving takes it's toll. But as for alignment, I usually do this:

1.) adjust both rear cambers to least amount of negative I can, and whichever wheel is the most neg, I match it to keep them the same. If at all possible go .4 degrees negative. I usually have to match at .6 in most cases. The key is to stand the tires up more, but keeping some Neg. camber for stability. It this point, the car will still corner like no other.

2.) adjust rear toe to factory spec (alignment machine tells the tech this)

3.) Do the same on front camber, stand them up as much as possible, never go positive. I like to put the front left wheel at .3 and the front right at .5 or .6 reason being is that it will not create a drift, and it lessens the effects of road crown pulls.

$.) adjust front toe to factory specs.

Is that a dollar sign?!? Oh well....

Tips on dealing with alignment techs:

Understand that for an alignment technician, they get paid 1.5 hours for the job and they can do a good alignment in 15 minutes with a digital rolling compensation alignment machine. Sometimes that actually have to "work" for that money and spend an hour on a good alignment. If they don't want to spend the extra time to get that alignment to what you want, it will show on the print-out. I forget if the SC had any struts... I am an idiot today... I haven't worked on an SC for a while. But the adjustments on a strut involves loosening and re-tightening bolts on the strut to knuckle mount. They will only adjust so much, and the answer to adjust more than what it will go is a process called a "strut grind" where the strut hole (top one) is wallowed out by grinding it. Some techs like to charge extra... ABSOLUTELY DIRTY POOL!!!! This is why the alignment pays 1.5, for when all adjustments will have to be made with their various processes! Don't let ANYONE try to pilfer money out of you for this!!! DEMAND they do what is rightfully included in this service that you are paying for! Okay, just remembered the rear is adjustable cams, and I believe the front is a short-long arm suspension.... still can't remember the front.. ARGGHHH!!!

Anyways, I must add that I am a perfectionist when it comes to alignments, and I take them way too far and take a lot of time to get vehicles aligned perfectly. That is where all these tidbits come from. Maybe that is why I am not the alignment tech at Tom Wood Lexus (I do some of them, but there is a tech there who does them all day, he is extremely good, his name is Tim and you will not be disappointed in his alignments)

I don't want to give anyone a bad name in the auto world, but the reason I give you a section on dealing with alignment techs in because many indy shops out there will do shoddy jobs to make a quick buck. Best to take this to the dealer, it cost an extra R$30 more (where I work) than an indy for an alignment, but it is a professional job. Another thing is to make sure you are getting this alignment done on a HUNTER DSP machine!!!

Now this is set aside to make sure you don't over-read this... HUNTER DIGITAL MACHINE DIGITAL!!!!!!!!!!!!!!

Lasers are accurate, but techs do shoddy work on them because they take a lot of time to set up and will skimp on the work! I can teach you why, but it would take 40 hours of lecture, so just stick with a hunter DSP series DIGITAL!!!! alignment machine.

I can go on and on about alignments, but this much info will get you the best alignment possible. If you can, go to a dealer with the DIGITAL!!!! machine.

Now for the tires.... If you go to regular tires, make sure your SC has a mini-spare. They are equipped with run flats because putting a spare in the trunk takes a lot of space. There is a conversion trunk kit available from the dealer to make the space go in a specific place and look pretty. Have no idea on cost, but it is a must of going away from run-flats. That is the cons of run flats, you will need a spare if you get a flat, they won't run! Pun intended!

Last note: I don't want Tom Wood Lexus to get a bad name with this guide floating around with specs that will get some "red" on the alignment machine. Note that these custom alignment specs are to save tires. So why does the factory send out cars with so much negative camber that will wear out tires so fast? Answer: you think the factory cares about tires wearing out fast? If your SC gets at least 20K then they don't care. Not that they want you to buy tires more often, but more negative camber will make the car more stable in cornering and makes it so Lexus can say : "our car can do the slalom 2 seconds faster than their car!"

Okay, thats it I am taking this post too far! Go get that alignment now that you are armed with this info! Get every dollar's worth! Go to the Dealer!

Jesse A. Lane

P.S. DIGITAL!!!!!!!!!!!

[TomWoodLexus]

Oh shoot... I messed up on that first post where I said from 02 to .05! That makes no sense!!!

usually factory makes them 1.5 neg, and I take them to .5 neg. I have no idea what I was doing when I posted that first time! I am so sorry if anyone cut and re-welded their swingarms thinking they needed to go .05!!!!

<bangs head on table>

EDIT: I am sorry cmartin248, I should have read your full post before answering! I made the previous post without reading that at all! then this on after reading some, and now an edit after reading all of it.

Anyways, that last post will answer many of your questions.

For the 4 seater thing... it is not a 4 seater, but a 2+2 seater. Whats the difference? Insurance rates. If it was a full blown 2 seater, just imagine what kind of rates you nwould have.... easily double. That is the thought behind it.

Also remember to rotate tires after every 5K, each wheel wears a tire a tiny bit differently, and you want each tire to get the same wear as eachother.

SC tires will still wear out faster than a regular car, but they are not regular cars, they are... super awesome look good cars!!!

Fair power? maybe, I do prefer to call them sluggo's. They need begger engines. Yeah, they move, but the way they look, you would expect that buger to move movemove!!!

[Bob in Tucson]

Not only is the short tire life very expensive, its wasteful, and sends 4 tires to the landfill every 10k miles. I bought the 2003 SC430 with 130k miles on it and it had run-flat tires with less than 10K on them and they were worn out. The wear is only on the inside edge as most of you know and was about equal on all four tires. My first idea was to get the alignment fixed, but after taking it to a guy who is really good with alignment, it was dead on for the factory settings. My next move was to buy non run-flats and get the 30-40k that some people on here were bragging about. The new set of bridgestones didn't do any better and got around 10k before they gave up. Now is was time to do some measuring. I used simple tools like levels, eye site, and a home made toe-in guage. The first thing I notice was a lot of negative camber. Next, was a little toe-out on both the front and rear wheels. I jacked the rear end up and removed both wheels. Took all the negative camber out that I could, and put just a slight toe-in (1/16"). Moved to the front wheels and because they didn't have as much factory negative camber, I only moved the camber about 4 clicks in the positive direction. Then I brought the toe-in to about 1/16" also. I still feel the rear wheels have too much negative camber, but the only way I get more positive is to modify the swing arms. The front camber is about where I want it. A lot of you will want to know how much camber, but I only used a bubble level and I don't have anyway to measure it. I talked to the Lexus dealer and he said nobody was getting more than 10-12k on the run-flats. It seems if you are one of the lucky people getting good mileage on your tires, then your camber is not set factory. Lexus puts tons of negative camber on the car to improve the handling under extreme driving conditions. If you are like me and drive normal without doing the teenager drifting thing, then talk to your alignment guy and have him set your car up for your type driving. He can't alter the factory specs unless you approve it. I waited to write this until I had 5k on my new tires and they appear to be wearing very evenly and no sign of inside wear. Drop me a line if I can help....

Okay. I'm a new 02 SC430 owner. Love the car! New run flats also (Bridgestone front, Dunlops rear). First set (Kumho) ate themselves up at 13k miles...ouch! What can I take to the tire shop in the way of a sheet of instructions re alignment specs and say "here...align them this way".

[TomWoodLexus]

Tell them to stand the tires up as much as possible. Like..... -0.2 or 0.0 in rear, same for front.

Other thnan that, wide tires wear alot on the sides when turning. Lots of scrubbing action!

Remember, this might register as out of specs, but any alignment tech will know it's okay for saving tires, also remember you won't be doing the slalom very well!