Drifting Issue - Help!

[rjacket]

So I had 4 new Potenza RE960's put on about 4k ago.

I then had them aligned as there was a severe pull.

Sure enough, the alignment showed that my right front toe was over the max spec.

So driving the car along, it definitely feels balanced and aligned.

However, the car drifts right on FLAT roads.

So I take it back to the alignment shop and they say it is still aligned. I then have the tires rotated and balanced (back to front directly as they are unidirectional) and the problem is exactly the same.

So clearly the tires are ok since the 2 backs are behaving exactly like the 2 fronts.

I look back over my secondary angles and the SAI shows the following;

Left below min spec by 1 degree. Right above max spec by 2 degrees. At the alignment nothing was changed.

I read that on some cars SAI cannot be changed. So my question is, is this the cause of my drifting? And can anything be done?

Thanks!

 

[38sho]

first off toe doesn't make a car pull........

if your on an alignment rack, and your left toe is -.2 and your right toe is 0.0, when you drive down the road, your wheel will be off to the right and both front toe readings would be .1

they will self center themselves, this is why you get misaligned steering wheels and wear your tires..... it most certainly won't make the car pull...

what are your actual camber and caster numbers?

it is possible both your right side tires have radial pull.... maybe not that likely though.

Im not quite up to date what would be a good drift setup

but your alignment should have about equal camber numbers on both sides, say -1.0 degrees on both sides

and you should have equal or slightly more caster on the right side

something like 3 or 4 or 10 degrees, they vary from car to car. The chrysler 300 series cars use like 10+ degrees caster as the spec. While a 57 Chevy might have .2 degrees caster as its spec.....

3 on the left and up to 4 on the right for caster would be acceptable. I usually try to keep the tolerance within half a degree though


if your pulling right make sure you have more caster on the right side, and make sure you have slightly more or equal negative camber on the right side...... both sides should be negative camber on your setup. if you have -.5 degrees on the left and 0.3 or even 0.1 on the right side the thing will constantly track to the right

 

[5sfe91]

Aren't cars suppose to drift to the right a little bit for safety reasons?

 

[rjacket]

Ok, here are my specs

Front

Caster Left min 6.6 max 8.1 act 7.2
Caster Right min 6.6 max 8.1 act 7.2
Camber Left min -1.1 max 0.4 act -0.6
Camber Right min -1.1 max 0.4 act -0.6
Toe Left min -0.05 max 0.2 act 0.05
Toe Right min -0.05 max 0.2 act 0.05

Rear

Camber Left min -1.9 max -0.4 act -1.1
Camber Right min -1.9 max -0.4 act -1.3
Toe Left min 0.05 max 0.35 act 0.2
Toe Right min 0.05 max 0.35 act 0.2
Thrust Angle act 0.0

Secondary Angles

SAI Left min 8.6 max 10.1 act 7.5
SAI Right min 8.6 max 10.1 act 12.3

Included Left act 6.9
Included Right act 11.7

Setback Front 0.0
Setback Back -0.1

Track Width Diff 0.3
Wheel Base Diff 0.1

 

[PandaBear]

Originally Posted By: 5sfe91
Aren't cars suppose to drift to the right a little bit for safety reasons?


where did you get that idea from?

 

[38sho]

your setup looks good, you either have a tire problem, or their machine is not calibrated, or they printed out some kind of false readings just to make the print out look good

take it to another shop to see if they will give you a free print-out of your current alignment angles and compare!

 

[firefighter]

Maybe I missed it, but what kind of car is this?

 

[spasm3]

It would not take much brake drag to pull you to one side, even the slightest different in brake drag on the right wheel would do it. Does the car still drift when you apply the brakes or does it stay straight?

Also how many miles on the wheel bearings? worn, out of grease on one side could also affect this

 

[rjacket]

Originally Posted By: 38sho
your setup looks good, you either have a tire problem, or their machine is not calibrated, or they printed out some kind of false readings just to make the print out look good

take it to another shop to see if they will give you a free print-out of your current alignment angles and compare!


Thanks. Would you be worried about the SAI being out of spec?

 

[rjacket]

Originally Posted By: firefighter
Maybe I missed it, but what kind of car is this?


2007 Lexus GS350 RWD

 

[rjacket]

Originally Posted By: spasm3
It would not take much brake drag to pull you to one side, even the slightest different in brake drag on the right wheel would do it. Does the car still drift when you apply the brakes or does it stay straight?

Also how many miles on the wheel bearings? worn, out of grease on one side could also affect this


I haven't observed what happens when braking as I am generally holding onto the steering wheel straight when braking! I will take a look.

The car had 27k on it when I had the alignment done. It now has 31k. Haven't seen greasing wheel bearings as a maintenance item so I presume it hasn't been done.

 

[spasm3]

Sealed bearing units should not be bad at only 31k so i would try another alignment shop next.

 

[cchase]

Originally Posted By: 5sfe91
Aren't cars suppose to drift to the right a little bit for safety reasons?


Maybe you're thinking of the fact that most roads have a crown and will make a car drift off to the right?

 

[CapriRacer]

Swap the front tires - left and right.

1) If the direction of the pull changes, then you have a tire only ptoblrm.

2) If nothing changes, then you have an alignment only problem.

3) If the pull disappears or is different (except for a complete change of direction) then the problem is bpth tires and alignment.

But this doesn't count if there is a brake drag problem - and that sounds like what you have.

 

[firefighter]

I checked out TSB's (tech services bulletins) at work today and there was one for your car, in referance to drift diagnostics. From my experience when a manufacture issues a bulletin for drifting or alignment the cars are generally a chore to align, and susceptible to the type of tire. Were these tires approved for your car. I know of one Mercedes that you are not supposed to run a certian michilen tire cause it can cause a pull that also came out in a tsb. I did not get to read the whole bulletin, but if you ruled out tires as the problem you may want to take it to the lexus dealer for an alignment as they may have a little more experience with this problem, Hope this helps

 

[rjacket]

Originally Posted By: firefighter
I checked out TSB's (tech services bulletins) at work today and there was one for your car, in referance to drift diagnostics. From my experience when a manufacture issues a bulletin for drifting or alignment the cars are generally a chore to align, and susceptible to the type of tire. Were these tires approved for your car. I know of one Mercedes that you are not supposed to run a certian michilen tire cause it can cause a pull that also came out in a tsb. I did not get to read the whole bulletin, but if you ruled out tires as the problem you may want to take it to the lexus dealer for an alignment as they may have a little more experience with this problem, Hope this helps


Thanks for that. I think I saw this tsb for the 2006 model year. If you can post a link to it, then that would help when I go to the dealer.

 

[rjacket]

Originally Posted By: rjacket
Originally Posted By: spasm3
It would not take much brake drag to pull you to one side, even the slightest different in brake drag on the right wheel would do it. Does the car still drift when you apply the brakes or does it stay straight?

Also how many miles on the wheel bearings? worn, out of grease on one side could also affect this


I haven't observed what happens when braking as I am generally holding onto the steering wheel straight when braking! I will take a look.

The car had 27k on it when I had the alignment done. It now has 31k. Haven't seen greasing wheel bearings as a maintenance item so I presume it hasn't been done.


OK I did same braking today without holding the steering wheel, and the car continued to drift as it braked.

Does that mean I can rule out the brakes as the cause?

 

[firefighter]

I will check the tsb and get the # when I go to work. In your original post you said you had the tires put on 4K ago then you had it aligned cause of a pull. Did you have any of these problems with the old tires? Did you have a drift with the old tires? I would hate to see you spend this money doing all these alignments and it is the tires any way. I see you rotated the tires front to back, it is not all that unlikely that you could have to bad tires on the same side. you should try switching the tires across the front. I know they are directional but for a little test drive it will not hurt them, and then see what happens. If it didn't do it before and it does now what changed. I will still get that tsb info though Hope this helps

 

[charbaby]

Originally Posted By: rjacket
Originally Posted By: firefighter
Maybe I missed it, but what kind of car is this?


2007 Lexus GS350 RWD


Before I read/scrolled down this far, I was going to say Toyota/Lexus...No Lie! After driving many Toyota products over the years, I notice this with just about all of them. They glide slowly toward the shoulder of the road. This can be fixed! Just buy a set of G/Y's. And when the car really pulls hard toward the shoulder of the road, switch the two fronts with each other.......FIXED!......................................JK!

Originally Posted By: CapriRacer
Swap the front tires - left and right.

1) If the direction of the pull changes, then you have a tire only ptoblrm.

2) If nothing changes, then you have an alignment only problem.

3) If the pull disappears or is different (except for a complete change of direction) then the problem is bpth tires and alignment.

But this doesn't count if there is a brake drag problem - and that sounds like what you have.


My suggestions too. Swap the two front tires with each other.
Many tires have radial in my experience. I have trouble with G/Y's mostly.

 

[charbaby]

I meant to say "Radial Pull"