Do OEM coil springs actually sag over time?

Does anyone have hard measurements of 5th Gen coil springs sagging over time when used under a typical light duty use?

I ask because I'm approaching 140k miles on my 4R. At 100k I installed Bilstein 5100s with the front on the .85 setting.

I am very pleased with this setup and plan to simply replace the 5100s at the next big mileage milestone. I'm wondering if there's a point where the OEM springs actually start to sag / lose height.

Again, this is typical light duty usage. Completely unloaded 90% of the time, with just me (160lb) as the daily driver. Wife and toddlers ride with me on the weekends. Once or twice a year I load the family up for beach trips, which means a full load of luggage in the rear plus the family.

 

I just went on a road trip to SD meet my friends. They have a 4th gen 2003 4R. I looked over the car and did the switch to summer tires for them. That car is in amazing shape for a 20 year old car. The interior is mint, no rust at all, and only about about 150K miles. I didn't notice the rear end sagging at all.
I was worried about that car for nothing.

 

I agree with you, Afret in that 4th gen is best made 4Runner so far. Minor things over many years but no major or visual changes such as rear sag on 3rd gens. I've both 4th gen and 5th gen (2004Sport & 2013Trail). For light, moderate or serious off road use these vehicles will not fail you if set up and used properly.

 

All spring sag over time.

 

^^Coils, torsion bars, leaf springs…they all will sag over time.