Questions

[backroads]

In November I bought a 2016 Sonic LT Hatch, with 205/50-16 wheels, and have been happy with it, except that after 1100 miles of driving I would like a smoother ride from the rear suspension. I’ve reduced air pressure in the rear tires by 3 psi but want further improvement. If anyone knows the answers to the following questions, or can direct me to a source, I would appreciate it.

Does the LTZ have a softer rear shock than the LS/LT? I thought I read that in a post somewhere, but from what I can tell on the 2016 parts diagram, for non-RS cars, there is a rear shock for 15” wheels and one for 16/17” wheels.

Also, is there a measurement that can be used to compare stiffness of an aftermarket shock to the OEM shock?

What is the rear spring rate for the LS/LT/LTZ, assuming they are the same? What is the rate for the RS? Perhaps I might investigate a custom spring that is the same magnitude softer from the stock LT spring as the RS is stiffer.

Can the “alarm” setting for the tire pressure monitoring system be changed? Prescribed air pressure for these tires is 35 psi front and rear and the dealer said it would probably go off around 31 psi. If I end up running with reduced pressures I would prefer an alarm setting proportionately lower.

Thanks for your help and insight.

 

[JBScat]

Funny Im the exact opposite, I thought the rear was too soft.

One thing you need to keep in mind is that the car has a short wheelbase, there is only so much you can do for the ride. I am pretty sure they all have the same shocks and springs if its a non RS model.

 

[Natesriv]

Can't change pressure

 

[Maddmatts]

The RS will have a slightly stiffer spring since it lowers the car a little. There are 3 different part numbers for the rear dampers with notes on which size of wheel they're meant for. One of them might be valved for the RS's springrate. GMpartsdirect.com doesn't give more specific information than that.

One suggestion I know that will work is to replace your 16" wheels with a set of 15's. The increased tire profile will add a little more squish. There's a noticeable increase in softness between my 17's and 16's for winter.

 

[backroads]

Thanks. I was mistaken about my tire size -- they are 205/55, not 205/50. Either way, I understand how the 195/65-15 tires would have more sidewall flex.

Could the brand of tire contribute to ride quality? I have never owned Hankook before (Hankook Optimo 428.) I mostly use Yokohama, some General.

I still think the answer is in the springs/shocks.