Z82 is the RPO code for GM’s factory trailering package. It runs from the Squarebody era right through to the current trucks, which makes it one of the longest-lived codes on a Chevy or GMC label — and one of the most misread, because what it includes is not the same in 1990 as it is in 2026.
What Z82 includes, by generation
| Generation | Years | What the factory documents list | Source |
|---|---|---|---|
| T1XX | 2019–2026 | Trailer hitch, 7-pin and 4-pin connectors, and (CTT) Hitch Guidance. On 2019 HD applications the platform hitch is described as 2.5-inch with a 2.0-inch insert, with a 7-wire harness on independent fused circuits. | 2021 Silverado 5W4, 2023 Silverado SSV, 2026 Silverado 9C1 guides |
| K2XX | 2014–2018 | Trailer hitch, 7-pin and 4-pin connectors. The hitch is Class IV, rated 11,000 lb. | 2016 and 2018 Silverado 5W4 Municipal Specification Guides — both documents word-for-word |
| GMT900 | 2007–2013 | Recorded as “heavy-duty trailering equipment”. Component list not documented. | 2007 Chevrolet Silverado Classic Truck Restoration Kit |
| GMT800 | 1999–2006 | Recorded as “heavy-duty trailering provisions”. Component list not documented. | 2000 Chevrolet C/K & Silverado Truck Restoration Kit |
| GMT400 | 1988–1998 | Recorded as “heavy-duty trailering equipment package”. Component list not documented. | 1990 Chevrolet Truck Vehicle Information Kit |
| Squarebody | 1973–1987 | Recorded as “Trailering Special package”. Component list not documented. | 1973 Chevrolet Truck Vehicle Information Kit |
The Class IV, 11,000 lb figure on the 2014–2018 trucks is the most useful number on this page, and it comes from two independent GM municipal guides that state it identically.
Z82 is not a tow rating. It is the equipment. What your truck can actually pull depends on the axle ratio, the engine, the cab and bed, and the GVWR — all of which are their own codes on the same label.
How to check what your truck actually has
- Find the RPO label — glove box, console lid, or under the spare.
- Decode Z82 for your model year — change the year to yours.
- Look for the codes that set the actual capability beside it: the axle ratio (GU6 is 3.42, GT4 is 3.73, GT5 is 4.10), the differential (G80), and any cooling codes.
A label with Z82 and a 3.42 axle is a different truck from a label with Z82 and a 4.10, even though both say “trailering package”.
If your label is a QR code
On 2018 and newer trucks the glove box label often carries a QR code instead of the printed list of three-character codes. Scan it with your phone camera, then paste what comes back into a text message or a notes app — phone cameras tend to show it truncated, and pasting it is the easiest way to read the whole thing.
It is not a web link. It is one long comma-separated line: VIN, model year, model, build date, order number, then a group of three-character codes separated by spaces, then the paint code. That group is your RPO list — paste it straight into the RPO decoder.
What Z82 gets confused with
- NHT — the Max Trailering Package. A step above Z82, with a heavier axle and its own cooling. If your label has NHT, you have more than Z82.
- Z71 — on 2023 trucks Z71 requires Z82, so the two turn up together constantly. They are not the same package and Z82 is not off-road equipment.
- CTT — Hitch Guidance. Part of Z82 on current trucks, but it also appears on its own.
Sources
- 2016 Silverado 1500 Special Service 5W4 Crew Cab Municipal Specification Guide, GM Upfitter (rev. 12/6/2015)
- 2018 Silverado Special Service Municipal Specification Guide, GM Upfitter (rev. 6/27/17)
- 2021 Silverado Special Service 5W4 catalogue, GM Upfitter
- 2023 Silverado SSV Specification Guide, GM Upfitter
- 2026 Silverado 9C1 Police Pursuit Specification Guide, GM Fleet
- 2007, 2000, 1990 and 1973 kits, GM Heritage Archive
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