S70 alignment

bguzz · Post by **bguzz** » 29 Apr 2013, 13:19

I have an issue where my 98 S70 pulls to the left. It isn't horrible, but consistent. I had it aligned and it still did it even though it was in close to in spec. So I thought it was a worn suspension. Eventually I rebuilt it. I did struts/shocks, control arms, inner and outer tie rods, strut mount seats (the rubber things), springs, sway bar links and drivers side axle. I got it aligned again and it is within spec...and it pulls again just like it did before? Any ideas of what's going on? The camber isn't exactly in speck, but the shop tells me they can't adjust that.

Post by **erikv11** » 29 Apr 2013, 13:27

Are they doing a proper 4 wheel alignment?

I wonder if there is a thrust angle problem in the rear, or if the car is not "squared" properly.

Post by **cn90** » 29 Apr 2013, 14:35

For a proper alignment in any vehicles, there are some generic guidelines:
- No previous major accident
- Suspension parts in decent shape, no worn ball joints (control arm or tie rod).
- Tires in the same axle should be same make/wear.
- I use tire pressure 37 psi (cold) all around.
- No heavy cargo in the trunk
- Full fuel tank
- No passengers in car (BMW is a bit different but that is a different topic).

- Front Camber is adjustable, I just did this myself over the weekend:
* I measured mine and it was -2.0 degrees on the RF tire.
* Mark the knuckle-strut relationship with sharpie.
* Remove wheel, loosen the 17mm/18mm nuts/bolts that hold the knuckle.
* Drop the knuckle down as much as possible.
* Tighten the 17mm/18mm nuts/bolts (search forum for torque values etc.).
* Re-measured the camber, now it is -0.5 degrees.

- I also adjusted the toe-in to be 1mm on each side. Car runs straight like an arrow.

One of these days, I will write a detail DIY on how to align your car at home. Right now, I don't have time.

bguzz · Post by **bguzz** » 29 Apr 2013, 15:22

Very interesting...thanks. How do you measure the camber? Mine is -2.7 I think. Could that cause a pull?

Post by **matthew1** » 29 Apr 2013, 15:32

Hey CN, didn't you already?

DIY Alignment topic

jdmack · Post by **jdmack** » 29 Apr 2013, 15:34

Just my two cents but there is a phenomenon known as radial tire pull that I have recently had an issue with after installing a new set of tires,(just something to think about) Tire Rack has a good how-to write up on this if you think this could even remotely be the issue.

Post by **cn90** » 29 Apr 2013, 15:53

matthew1 wrote:Hey CN, didn't you already?

DIY Alignment topic

Hi Matt,

I did that write-up. But I recently discovered a simple trick, basically a simplified version of the link you posted. It is very nice and easy.

As promised, one of these days when I have more time, I will post a detailed DIY.

-------
@bguzz,

Camber: assuming you have a level garage (garage floor from R to L should be level):
- Park with front facing out.
- wheels straight ahead
- Leveler + Carpenter Square combo tool (see link above): place tool vertical and measure at rim 6 o'clock and 12 o'clock positions.
- Angle the tool outward a bit, in such a way that bubble in the leveler is level.
- Measure the gap between the tool and the rim.

- Now convert that to angle (degrees) using arctan.
- Calculate arctan of (measure gap btw tool and rim at 12 o'clock/diameter of the rim in mm). Any scientific calculator can do this.

Basic trigonometry. If one did not sleep through high-school trig, one can do this lol.

Again, I will post some photos later.

Post by **JRL** » 29 Apr 2013, 16:21

-2.7!!!!! Negative camber?
In the front?
That will cause pulling
Swap tires side to side first
Sometimes cars just pull to one side or the other. To correct a slight pull a good alignment person will compensate by adjusting the camber on the side that pulls.

I just had to do this to a P2 car, pulled a hair to one side with new tires and a new alignment
He adjusts the camber to slightly pull to the other side and if the person knows what he's doing, it works

Post by **erikv11** » 29 Apr 2013, 16:26

I don't mean to beat a dead horse and I agree there could be other explanations but I am still curious: who is doing the alignment, are they doing a proper 4-wheel alignment?

If the rear isn't aligned first, and the front is not squared up with the rear (sorry I do not recall the proper term), then nothing you do up front will solve the problem. On these cars you must start with a 4 wheel alignment. Then you can DIY up front, I have done it a fair bit myself. But plenty of shops have no clue how to deal with the trailing arms in an 850/x70 and so they just ignore the rear.

bguzz · Post by **bguzz** » 29 Apr 2013, 16:49

It was a Firestone shop and it was a 4 wheel alignment. They gave me the before and after specs and they clearly only adjusted the tie rods for toe in/out. I asked about how they adjust the rear and he said there was no way to on one so old...that there is a egg shaped bolt that corrodes and you can't do anything with it.