Front suspension settling overnight...
I measured before I left from the floor and the fender lip was 27 1/4 inches from the ground. Went out and ran some errands and measured after I parked and I'm at 28 3/4 right after shutdown. So, 1.5 inch drop in 24 hours strikes me as a lot, no? I measured the rears just now and they too are at 28 3/4. I will let it sit overnight and measure in the morning. The rear did not look low when I got into it this afternoon.
Thoughts?




Was it even on both sides, or was the left front lower than the right front?




I've been taking measurements (distance between the lower edge of the rim to the fender) over past 2 days:
Baseline: 27.25 inches (2 days "48 hours" measurement )
Distance between the lower edge of the rim to the fender):
- Baseline: 27.25 inches (day 1 morning)
- after 12 hours: 26.75 inches (day 1 night )
- after 24 hours: 26.75 inches (day 2 morning)
- after 36 hours: 26.75 inches (day 2 night).
- After 48 hours: 26.75 inches (day 3 morning)
Experiment is done. This confirms the air contraction theory for the W222 AIRMATIC system, during first 12 hrs only before it stabilizes, with around 0.5 inches due to air contraction. My observation is that this happens when ambient temperature of air inside suspension drops to 30-40F or lower, obviously leading to a lower air density and thus a smaller air volume in the suspension which causes the car to set lower.
**For the record, these measurements were taken at temperature of 32-35F. I expect the contraction to increase by another 30% based on air density at 15F or lower, meaning another 0.25 inch for a total of 0.75 inches at colder temperatures such as 20F or lower.
Based on this, 0.75 inches of height difference is within design parameters, however, for those who experience more than 1-inch of height difference overnight, i would encourage them to test for any potential air leak especially during summer or when temperature is not that low. Suspension drop is fine in cold, but in summer it should be minimal
If you experience a height drop that's outside the normal numbers/parameters above, It's likely that there is a leak somewhere.




Each night and morning, I would measure all 4….from floor across axle c/l up to fender lip edge. Nothing was consistent.
Fix was a combination of struts, maybe compressor and valves. Wasn’t rocket science but not a job for a rookie tech w/o supervision. Went back with reman parts and all good after that. At the time, all covered by third pty warranty. Problem never again surfaced.
FYI…Problem can get worse and strand you.
I've been taking measurements (distance between the lower edge of the rim to the fender) over past 2 days:
Baseline: 27.25 inches (2 days "48 hours" measurement )
Distance between the lower edge of the rim to the fender):
- Baseline: 27.25 inches (day 1 morning)
- after 12 hours: 26.75 inches (day 1 night )
- after 24 hours: 26.75 inches (day 2 morning)
- after 36 hours: 26.75 inches (day 2 night).
- After 48 hours: 26.75 inches (day 3 morning)
Experiment is done. This confirms the air contraction theory for the W222 AIRMATIC system, during first 12 hrs only before it stabilizes, with around 0.5 inches due to air contraction. My observation is that this happens when ambient temperature of air inside suspension drops to 30-40F or lower, obviously leading to a lower air density and thus a smaller air volume in the suspension which causes the car to set lower.
**For the record, these measurements were taken at temperature of 32-35F. I expect the contraction to increase by another 30% based on air density at 15F or lower, meaning another 0.25 inch for a total of 0.75 inches at colder temperatures such as 20F or lower.
Based on this, 0.75 inches of height difference is within design parameters, however, for those who experience more than 1-inch of height difference overnight, i would encourage them to test for any potential air leak especially during summer or when temperature is not that low. Suspension drop is fine in cold, but in summer it should be minimal
If you experience a height drop that's outside the normal numbers/parameters above, It's likely that there is a leak somewhere.
Measured this morning, so it was parked about 5:00 and its now 10AM, so 17 hours and I measure 28 1/8th inches, so overnight it only settled a little over 1/2 inch.
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