With 93k miles on my 2006 G35x sedan, the ride was getting pretty rough. Noticeably so since I bought the car a year ago with 78k miles. A few weeks ago I had the shocks and struts replaced, and driving away the ride felt much nicer. However, about 1000 miles later the ride is now quite firm again. You can feel every bump on the road. It's better than it was before I replaced the shocks/struts, but does NOT feel like a new suspension should feel.

I think they installed KYB Excel-G struts and I provided the Monroe OEM-style rear shocks, so it's not an aftermarket suspension.

Is there typically a long break-in period for shocks and struts? Any ideas here?

 

Did you have all the rubber parts changed also? The rubber parts age and get stiff. Check a suspension
Schematic and you will see the parts. They are cheap but your gonna have to redo the job if you want that new car feeling. Somewhere on this site this topic has been covered. The new stiff struts are pounding on stiff old rubber hence harshness..good luck.

 

Yeah, they replaced the mounts as well.

 

I know this is an old thread but hope this helps I am on the same boat as far as suspension goes.. lmk if this helps! Over time the OEM rubber bushings deteriorate causing unwanted vibration and play in the suspension system. Energy Suspension offers polyurethane bushings that are a direct replacement for your 350Z or G35. The polyurethane material is far superior to rubber offering a product that is sure to last much longer than OEM.Kit IncludesFront Control Arm BushingsPower Steering Rack BushingsDifferential BushingsFront and Rear Sway Bar BushingsSubframe BushingsRear Control Arm Bushings*

*

I believe vendors on here sell this master kit for our cars.

 

I have had ES compression rod bushings on my car for about a year now. They were fine with the old struts but I'm wondering now if they might be the cause. Usually poly bushings make everything stiffer, which is why I won't put any more poly on the car.

 

Oh and I have been to two shops who have checked all the bushings and they say everything appears to be fine. The shop that installed the struts said they noticed a firmer ride but don't know what it is. They said maybe the struts need some breaking in, but it has been over 1500 miles now.

 

Not a fan of KYB shocks.

Without much in the way of suspension option's for the AWD G35X, you don't have much you can do.

If you love the can enough and have the cash. You should be able to have Bilstein make custom front shocks. They'd need at least one oem front shock to copy. They'd also need some other technical stuff like car weight, weight dist front/rear, wheel rates (F: .688 R: .649) spring rates 283/308. You'd also want their rear shocks and have them revalved accordingly. You'd want to speak to their San Diego office and ask for Ramon.

 

Custom built Bilsteins? I'll pass.

 

Update:

I went back to the shop that installed the struts and they replaced them with Monroes at no cost to me. I immediately noticed an improvement over the way it was before, so it appears that was part of the problem.

The ride does still feel a little stiffer than I expected, though. Is it possible that the Energy Suspension compression rod bushings could be the cause, or should those not affect the ride quality at all?

 

The ES Bushings will make the car ride stiffer. Poly is harder and doesn't flex much like the oem bushings. It's something you'll have to live with or get oem bushings and replace again.
When i first changed my comp rod bushing with ES. I noticed right away that it rides stiffer. But now after 5months i need to spray lube on them often, or else i get cluncking/rattling sound.