My car is crooked...

[MD18EcoStang]

2018 Ecoboost PP, and I've yet to do any suspension mods, but I'm prepping to change that. Many of the videos I've seen for lowering spring installation suggest measuring the before (stock) height, from the ground straight up to the fender. I lined my tape measure up vertically through the wheel center. Measurement was done in my garage, so the surface is flat. I have to say, I was surprised by what I found:

28-5/8" (FL) (FR) 28-1/2"


28-1/8" (RL) (RR) 28-3/4"

Yes, the front of my car is 1/2" higher on the driver's side and 1/4" lower on the passenger side! This caused me to double and triple check my measurements. I'm not inclined to do anything else to the suspension until I get this sorted out. Where to begin? It seems the biggest outlier is the left rear measurement. Could there be a problem with a stock component?

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[Siege]

Don't forget to clock your bushings after you lower it.

https://www.mustang6g.com/forums/th...hose-bushings-after-lowering-your-s550.44129/

 

[Michael_vroomvroom]

Did you clock your bushings after lowering it?

https://www.mustang6g.com/forums/th...hose-bushings-after-lowering-your-s550.44129/

Think OP has not lowered his car yet, he wants to find out the reason for the difference now (stock).

Have you measured your floor really is flat? If you turn the car around (e.g., reverse in, if as measured above, you drove front in), do you get the same numbers?

 

[Norm Peterson]

Have you measured your floor really is flat? If you turn the car around (e.g., reverse in, if as measured above, you drove front in), do you get the same numbers?

This ^^^

A laser level on a tripod would be one appropriate measuring method, checking side to side at your wheel locations. For cheap, maybe a U-shaped clear water tube with the verticals spotted at the wheel locations (also side to side) might work.


Norm

 

[Mike Pfeifer]

I’ve always been taught that to properly measure ride height, measure from the bottom lip of the wheel, through the centerline of the wheel to the edge of wheel opening. If you measure from the ground, you are also measuring the tire.

That said, I had a BMW 3 series almost 20 years ago that I wanted to make into an autocross car. I discovered it sat about 1/2 inch lower on the right rear and spent quite a bit of money trying to fix it. It didn’t matter what I replaced, it still sat 1/2 inch lower and the only conclusion I could come to was that it was in the body and not the suspension. I then promptly sold it.

 

[Joe B.]

If the surface is not level, the measurements will differ. I use a spirit level on a long straight 2x4 to check and have a dead level spot in a parking garage I use.
Did you turn the car around and check again?

 

[MD18EcoStang]

Don't forget to clock your bushings after you lower it.

This is a good thing to remember. That said, after posting, I remembered that I did replace my vertical links, however, the only two bolts touched on each side were the ones that attach the link. Since the links are a stock replacement length, I can't imagine geometry/ride height could possibly be affected, unless there was some binding that occurred elsewhere when I lowered the cradle. It should have been pulled back into the exact prestock alignment during reassembly. Just doesn't seem to be the likely culprit in this case, although if I don't figure this out, I'll try loosening and retorquing the vertical link bolts.

 

[MD18EcoStang]

Think OP has not lowered his car yet, he wants to find out the reason for the difference now (stock).

Have you measured your floor really is flat? If you turn the car around (e.g., reverse in, if as measured above, you drove front in), do you get the same numbers?

Another good point, and again, I'll try this if I can't find another explanation. An easy check, but not at the moment, as I have a number of things disassembled, and I'm awaiting a part in order to put it all back together.

 

[MD18EcoStang]

I’ve always been taught that to properly measure ride height, measure from the bottom lip of the wheel, through the centerline of the wheel to the edge of wheel opening. If you measure from the ground, you are also measuring the tire.

That said, I had a BMW 3 series almost 20 years ago that I wanted to make into an autocross car. I discovered it sat about 1/2 inch lower on the right rear and spent quite a bit of money trying to fix it. It didn’t matter what I replaced, it still sat 1/2 inch lower and the only conclusion I could come to was that it was in the body and not the suspension. I then promptly sold it.

I'm going to check this measurement today. I began taking some more measurements last night, and noticed some discrepancies in tire height, but they were quick measurements, so not as precise as I'd like to be.

 

[Mike Pfeifer]

Wow I just looked to see if I could find a picture to better illustrate ride height measurement but most are showing the incorrect methods (one method is technically OK, but difficult to be accurate - shows center of wheel to wheel opening edge. Depends on how good you are at estimating the center of the wheel). Using the bottom edge of the rim is the easiest to get a consistent measurement every time because you can just hook the tape measure on the rim and pull up and line up through the center of the wheel.

anyway, this is not a mustang, but the process is the same.

 

[MD18EcoStang]

EDITED after measuring again... I definitely mistyped one of the numbers. Below is correct current situation.

New measurements based on the bottom of rim straight up to the fender.

25-13/16" (FL) (FR) 25-3/4"


25-3/8" (RL) (RR) 25-13/16"

I'm trying to measure to the nearest 1/16". Clearly, tire "smoosh" contributed to some of the discrepancy, and I can work that out separately. I bought the car new in May 2019, about a year after it was built. I only have just under 5k miles on it in 2 years, so it has sat a lot, especially over the winters, and it's possible the tires could have developed some flat spots over time (although this isn't evident in how it rides). I'm not terribly concerned over the 1/16" difference in the front, but that left rear still seems to be a little concerning at about 7/16" lower than any of the other corners.

 

[MD18EcoStang]

Measuring accurately is easier said than done!

 

[NightmareMoon]

Could be the garage floor. Mine looks level, its not. Park backwards and see if it changes?

Could still be air pressure difference in the rear tires forcing one side up relative to the other. Make sure your tire pressures are equal.

Inspect rear bushings for tears.

Also, its a Ford, not a Rolls Royce, so a few fractions of an inch is normal. 1/2" is a bit much.

 

[GregO]

but that left rear still seems to be a little concerning at about 7/16" lower than any of the other corners.

You’re trusting that the body panels are perfectly placed on the substructure and the rear cradle is perfectly mounted to the substructure.
In all honestly so long as the alignment is spot on and the car doesn’t dog track measuring wheel well height will always be inconsistent no matter what vehicle.

 

[Mike Pfeifer]

You’re trusting that the body panels are perfectly placed on the substructure and the rear cradle is perfectly mounted to the substructure.
In all honestly so long as the alignment is spot on and the car doesn’t dog track measuring wheel well height will always be inconsistent no matter what vehicle.

There is a tolerance, but I have no idea what that spec might be. 1/16 of an inch is definitely OK. 1/2 inch? I doubt it. I have seen up to about 8mm difference on the BMWs I have measured over the years.

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