Pulling to right

[jakester850]

I have a 2010 Mustang GT. I installed lowering springs a month ago and had an alignment done. Also had the lower control arms replaced and the rear shocks replaced. Since then, or at least a couple days after, the car has been pulling to the right much more than before. Today, I took it back in again for another alignment where they fixed the front left camber. But still, it pulls to the right. Thoughts on why?
spring install

today

 

[crjackson]

I’m certainly no expert on the matter, but here’s what comes to my mind. I’m sure you’ll probably get better answers from others, but here we go …

With regard to the pulling
That could easily be a tire issue, rather than an alignment issue. Even if your tire wear patterns look okay, sometimes belt-shift and stretch, can occur (you can’t see that afaik), and that can definitely cause the car to pull. I’ve had that issue on more than one occasion, and on different cars.

Swap your tires (left to right) and see if that changes anything. If you have radial tire pull, this should cause it to pull in the opposite direction.

*NOTE: This all assumes tires are inflated properly.

Just my worthless 2¢

Here’s my alignment sheet.

 

[JC SSP]

I agree, swap two front tires and see what happens.

I did notice your Caster is out. Was this car ever in an accident? Caster will cause the car to pull. Also it has no adjustment from the factory.

 

[86GT351]

Is it a pull or a drift? When you let go of the wheel, does it just go right or does it gradually go to the right? Big difference. Cross rotating the tires might help.

 

[JC SSP]

Good point, pull vs drift which could also be the crowne of the road... make sure to try different streets to get the repeated results.

If it's pull, there is something in the suspension...

 

[OX1]

It will pull to the right on most normal non highway roads. You have 3/4 degree cross caster (higher on drivers side) and the normal crown in the road. Both will make it pull right. Combined, it could make it pull significantly.

Caster is not adjustable (without caster/camber plates), but normally when it is, you dial in a bit more on pass. side, to counteract the right leaning crown in road.

Not sure why it just started pulling, unless they somehow increased caster after replacing suspension parts (which is not that easy to do, unless there was some serious slop in bolt holes that mount lower control arm).

Caster Front
To adjust front caster, it is necessary to elongate the mounting holes in the front control arm mounting bracket on the subframe. Do not elongate the holes any more than indicated by the etchings on the subframe. This modification will yield about ±1.0º of caster. Tighten the nuts to 175 Nm (129 ft. lbs.). Adjustable upper strut mounts can be used to give ±2.00º of adjustability. But, this requires modification of the strut tower.

https://www.brakeandfrontend.com/2005-2010-ford-mustang-alignment/

 

[Juice]

Those alignment readings do not support a pulling condition.

I would also swap front tires side to side to test. Even if they are directional.
What brand, size and age are the front tires?

 

[mattjames]

The side with less caster is pulling, correct that to match the other

 

[Juice]

The side with less caster is pulling, correct that to match the other

Umm, caster is 6.6* on both sides.
There is a point four difference in camber. More positive on the right, this would add to the road crown effect.
Ps: years ago, the standard was to bias some right drift into cars for safety. Driver falling asleep will not cause a headon collision.

 

[mattjames]

Umm, caster is 6.6* on both sides.
There is a point four difference in camber. More positive on the right, this would add to the road crown effect.
Ps: years ago, the standard was to bias some right drift into cars for safety. Driver falling asleep will not cause a headon collision.

Only read the before, oops

 

[JC SSP]

Look at Jaskester850 first print out, that's the one with the pulling issue... (7.2 vs 6.5)

CRJackson has perfect caster... (6.6)

 

[Juice]

Look at Jaskester850 first print out, that's the one with the pulling issue... (7.2 vs 6.5)

CRJackson has perfect caster... (6.6)

I would not think that is enough of a difference in caster to feel it driving.
Waiting for the "tires swapped side to side" report.

 

[DieHarder]

I had a case where I experienced pulling to the right after new tires and an alignment. Wasn't apparent what the issue was at first. After a bit of looking around noticed the newby at the tire shop installed one of the front tires outside/in (i.e. many/most tires have a side that faces out). Not saying that's your issue but if you've had tires mounted recently worth a look.

 

[JC SSP]

Asymmetrical tires specify on the side wall which way to mount (towards outside).

FYI Unidirectional always have to be facing rolling forward...

The old Goodyear GSC were Unidirectional and Asymmetrical, so they were left and right side specific... LOL