Ford F-150 6-Inch Lift And 37-Inch Tyres: Is It Legal In Australia?
Yes, you can run a 6-inch lift and 37-inch tyres on a Ford F-150 and keep it fully road legal in Australia — but there's only one pathway that actually works. That's ORI's Stage 6 GVM (Gross Vehicle Mass — the maximum legal weight of the loaded vehicle) upgrade, engineered and approved under SSM (Second Stage Manufacture), and it has to be fitted before the truck is registered. A generic 6-inch lift kit and 37s bolted on after rego, without that SSM engineering, is not a legal setup — no matter how good it looks.
If that's the pathway you're after, here's exactly what it involves, who qualifies, and where people trip themselves up.
The Only Legal Way To Run A 6-Inch Lift And 37s Pre-Rego
Stage 6 is engineered and approved as an SSM package specifically to run a 6-inch BDS lift with 37-inch tyres, fitted before the truck is registered — and it's the only way this combination is legal Australia-wide.
There's no version of this where you buy a 6-inch lift kit and a set of 37s off the shelf, fit them to an already-registered F-150, and expect it to pass inspection or hold up under scrutiny. The lift height and tyre size push the truck well outside factory engineering, and without formal SSM approval covering that specific combination, it simply isn't a legal setup — regardless of how well it's built or how good the components are.
Why A Regular 6-Inch Lift Kit Isn't Street Legal
A 6-inch lift and 37-inch tyres is a serious change to how a vehicle sits, handles, and carries weight. Suspension geometry, steering components, wheel offsets, and load ratings all shift once you go this far beyond factory height and tyre diameter.
Fitting the parts is only half the job. Without engineering approval covering the modification as a complete package — suspension, wheels, tyres, and the resulting GVM and axle figures — there's no formal basis for the vehicle to be considered compliant. That's true even if every individual component is a reputable, well-made product.
This is where Stage 6 differs from a shop-bought lift kit. It isn't just parts — it's an approved engineering package.
SSM Approval Explained: What Makes Stage 6 Different
Stage 6 is approved under SSM — a regulatory pathway that allows a vehicle to be re-engineered and re-certified after it leaves the original manufacturer, before it's first registered. Under SSM, the modified vehicle — lift, wheels, tyres, suspension, and the resulting weight ratings — is assessed and approved as a complete package, rather than as a collection of individual aftermarket parts.
The SSM approval is what makes the whole vehicle, as modified, a legally compliant unit — not just a truck with some good gear fitted to it.
Why Stage 6 Must Be Fitted Pre-Rego
SSM approval only applies before a vehicle is first registered. Stage 6, along with Stage 5, is Pre-Rego only — it is not available as a post-registration upgrade.
Practically, this means if your F-150 is already registered, Stage 6 isn't on the table for that vehicle. It's not a matter of extra paperwork or a higher fee — the SSM pathway that makes the 6-inch lift and 37s legal simply doesn't extend to vehicles that have already been through registration.
Stages 1 to 4 are different — those are available both Pre-Rego and post-registration, which matters if your truck is already on the road (more on that below). One thing worth flagging if you go that route: fitting Stages 1 to 4 post-registration attracts additional local/state fees on top of the quoted stage price. That's not the case for Stage 6, since it's a Pre-Rego-only package.
Which F-150s Qualify For Stage 6 (And Which Don't)
Stage 6's SSM approval applies only to Ford Australia-delivered F-150 SWB (short wheelbase) and LWB (long wheelbase) Platinum, Lariat, and XLT models.
It does not extend to US-imported or grey-market F-150s without separate qualification. If your truck came in through a private import rather than through Ford Australia, don't assume Stage 6 applies to your vehicle by default — check this before you plan a build around it.
Stage 6 GVM Upgrade Specs: GVM, Payload, GCM And Towing Capacity
Stage 6 is ORI's largest lift and tyre package for the F-150 — a 6-inch BDS lift with 37-inch tyres — built specifically around that combination. It isn't ORI's highest-GVM stage; Stage 3 and Stage 4 carry a higher GVM (4,300 kg) and GCM (Gross Combination Mass, 8,800 kg).
GVM (Gross Vehicle Mass) | 3,700kg |
Payload (approx., SWB XLT reference) | 1,219kg (57.52% increase over factory) |
GCM (Gross Combination Mass) | 8,200kg |
BTC (Braked Towing Capacity) | 4,500kg |
Lift | 6 inch |
Front axle capacity | 1,700 kg |
Rear axle capacity | 2,000 kg |
Wheel offsets | +18, +12 |
Wheel load rating | 1,200kg |
Tyre size required | 37x13.5x20 |
Price (installed & engineered) |
The payload figure of 1,219 kg is a SWB XLT reference figure only. Lariat and Platinum variants carry different kerb weights, which changes the actual payload figure on those vehicles — don't assume the 1,219 kg number applies across every configuration.
Is 6-Inch Lift & 37s Right For You?
Stage 6 isn't a "best" upgrade to aim for by default — it's built for a specific outcome: the biggest legal lift you can do in a F-150.
If that's what you're after and your truck hasn't been registered yet, Stage 6 is the only legal way to get there. If you're not specifically chasing 37s and a 6-inch lift — if you just need more payload for touring gear, a canopy, or general load carrying — a smaller stage may get you what you actually need without the extra cost.
If your F-150 is already registered, Stage 6 (and Stage 5) aren't available to that vehicle at all — Stage 6 is Pre-Rego only. Stages 1 to 4 are available both pre and post registration, so if you're already on the road, that's where to start looking — just factor in that fitting Stages 1 to 4 post-registration adds state engineering fees on top of price, which doesn't apply to Pre-Rego.
For a full rundown of how all six stages compare, see our guide to the Ford F-150 GVM upgrade stages, from Stage 1 to Stage 6. And if you're weighing up whether you actually need 37s, or whether 35-inch tyres get you there with less hassle, which ORI GVM stage suits
35-inch F-150 tyres is worth a read too.
GET IN TOUCH ABOUT A PRE-REGO GVM UPGRADE
If your F-150 hasn't been registered yet and you're set on the 6-inch lift and 37-inch tyre combination, get in touch with BAW Automotive — as an ORI authorised dealer and certified GVM installer, we can talk you through what a Pre-Rego Stage 6 build looks like for your specific vehicle and delivery timeline.
If your truck is already registered, Stage 6 won't be an option — but Stages 1 to 4 are, and it's worth having a conversation about what actually suits your payload and towing needs before assuming you need the biggest package on the list.
FAQ
Can I fit a 6-inch lift and 37s to an F-150 that's already registered?
No. Stage 6 is a Pre-Rego-only SSM package. If your F-150 is already registered, this specific combination isn't available on that vehicle.
Are 37-inch tyres legal on an F-150 in Australia on their own, without the full Stage 6 package?
No. A 37-inch tyre fitment on an F-150 needs to be covered by an SSM-approved package — like Stage 6, which engineers the lift, wheel offsets, and GVM/axle figures together as one unit. Fitting 37s as a standalone tyre upgrade, without that engineering covering the whole vehicle, doesn't meet the same compliance standard.
Does a Stage 6 GVM upgrade increase my towing capacity?
No. BTC (Braked Towing Capacity) stays at 4,500 kg across every stage, including Stage 6. A higher GVM does not change what the vehicle is rated to tow.
Can I run Stage 6 on 18-inch wheels?
No. This SSM approval requires 37x13.5x20 tyres. On 18-inch rims, the rim contacts the tie rods on the new-generation F-150.
Does Stage 6 apply to a US-imported F-150?
Not without separate qualification. SSM approval for Stage 6 applies to Ford Australia-delivered SWB/LWB Platinum, Lariat, and XLT models.
