SteveDillon

I bought it used (but only 17k miles) so I can't rule that out, I've seen enough others on here with complaints about bouncy ride that this could be how it shipped from factory. Looking at prices on 4 shocks, it appears to be about $150-200 extra to go to Bilsteins compared to replacing all 4 with OEM, so i'll just upgrade.

Thanks for all the help, as per Gregs post which lists Z85 as standard suspension I don't think Z85 indicates anything special or "increased capacity chassis package". Gregs list shows Z85 as standard suspension which seems a lot more correct. I went to GM parts direct and looked up replacement springs RPO code 6PA and 7PA lead me to very generic springs used in numerous builds. For the rear spring codes ab<xx>, (abdk, abd3,abd,.abd4) lead you to rear spring rate. I don't see that code on my build sheet, but again the spring listed seems very generic. Shocks Rear are indicated with RPO code ad<xx>, Shocks front are chosen by a few codes. My shocks are pretty generic. I never saw z85 listed as a determining factor in picking Springs or Shocks. I'll be ordering bilsteins soon. I think this will be funny in a truck forum: earlier this year, I upgraded my 1993 Miata from original, still working, Bilsteins with 143k miles, to Fox Coilovers. Yup my tiny little Miata has Fox suspension.

The VIN is 3GCNWAEF8KG296715 , It has a u-haul labeled hitch , so not sure what towing package was included. I had scanned the QR code in the door and my deciphering of the RPO codes are as below. I might be overthinking, I'm just trying to figure out if Z85 changed the spring rate, or had uprated shocks that somehow I shouldn't be throwing out. The Bilstein site says "B6 4600" for front and rear for a stock ride height. 5100s for lifted. Truck won't be lifted, but will haul light farm equipment, and tow a car trailer for a street/track Miata. My 2 Miatas have springs that are 2-4x factory rates and adjustable dampers to match. I like a pretty firm ride. I think I should be buying 5100s but not matching dampers to a spring rate seems odd to me. Thanks for Any Advice, Steve 2019 Model Year CC10903 Model 07 Build Month 19 Build Year 01 Engineering Book? WQ Vehicle Order Number QJ08 ?? AKX AY0 Airbags, Dual-stage frontal airbags for driver and front outboard passenger; Seat-mounted side-impact airbags for driver and front outboard passenger; Head-curtain airbags for front and rear outboard seating positions; Includes front outboard Passenger Sensing System for frontal outboard passenger airbag A2S Seat adjuster, driver 4-way manual A52 Seats, front 40/20/40 split-bench A7E Seat adjuster, passenger 4-way manual C5U GVWR, 6800 lbs. (3084 kg) C67 Air conditioning, single-zone DLF Mirrors, outside heated power-adjustable D31 EF7 E63 Durabed, pickup bed FE9 Emissions, Federal requirements FJW GAZ Summit White GU6 Rear axle, 3.42 ratio H1T IOR udio system, Chevrolet Infotainment 3 system, 7" diagonal color touchscreen I19 ENGINEERING YEAR 2019 J61 Brakes, 4-wheel antilock, 4-wheel disc KW7 Alternator, 170 amps L82 Engine, 5.3L EcoTec3 V8 (AFM - Advanced Fuel Mgmt) MAH MAH - MARKETING AREA US, PUERTO RICO/USVI MSL PLANT CODE SILAO, MEXICO MYC Transmission, 6-speed automatic NB5 Exhaust, single outlet NK5 Steering wheel, urethane NTB QBN Tires, 255/70R17 all-season, blackwall QBR Tire, spare 255/70R17 all-season, blackwall Q5U Wheels, 17" x 8" (43.2 cm x 20.3 cm) RM7 Wheel, 17" x 8" (43.2 cm x 20.3 cm) full-size, steel spare RWL UDC Driver Information Center U2J Sirrius XM Delete U95 Audio system feature, 2-speakers V8D Vehicle Statement US WMK X88 7 Way Tailer connector Z85 Increased Capacity Chassis Package (Trailering Suspension) 1WT Work Truck 4AA (some interior trim code) 6PA (suspension code) 7PA (suspension code) 8X2 (suspension code??) 9X2 (Suspension Code??) 8624 Touch Up Paint Number - Summit White - WA-8624

Hello, Have a new to us 2019 that came out of fleet use (U-Haul). It has several towing goodies but not one of the standard trailering packages. I'm trying to track down what Z85 means in a WorkTruck, 5.3 AFM, Reg Cab, 8' bed. In prior years I have found it noted as increased towing capacity, or different shocks. I've been through the 2019 order guide and I can't figure out what exactly z85 means for a 2019. I'm asking because the truck suspension is very under-dampened, I've started to call the truck Bounce House. I have counted as much as 5 oscillations after a speed bump. Trying to find out if 'z85' changes my hunt for a shock with more or adjustable dampening.

AC Delco UPF63R w/ Amsoil Signature oil. Just because of RockAuto, I will use whatever higher quality filter and don't obsess too much over it. This year on the various cars I have used Napa Gold and Bosch also. I have a stack of Bosch for the 3 Mazdas in the 'fleet'.