Portal axles
A portal sets the half-shaft above the wheel centre, so the whole axle hangs higher off the ground. A lift raises the body and changes nothing under the axle — a portal changes exactly that. At a cost you need to know before ordering.
Where the clearance comes from
In a conventional axle the half-shaft runs through the wheel centre and the lowest point of the vehicle is the differential housing. In a portal axle a gearbox sits at the end of each half-shaft and steps the drive down to the hub — so the axle itself can hang higher.
Gear drive
Ratios of 1:1.2 and 1:1.33. The simpler design, running in an oil bath.
Chain drive
Four ratios, from 1:1.16 to 1:1.36. Chain in 50Cr-V steel.
Ratio change
A portal also changes the final drive, which partly compensates for larger tyres. A side effect, but a welcome one.
What a portal axle demands from the vehicle
This is not a part you bolt on and drive away. The figures below come straight from the manufacturer and all of them have to be met at once.
| Parameter | Value |
|---|---|
| Ratios — gear drive | 1:1.2 · 1:1.33 |
| Ratios — chain drive | 1:1.16 · 1:1.25 · 1:1.27 · 1:1.36 |
| Required lift | 4,5 cala |
| Wheels | 17 cali |
| Recommended offset | ET+50 |
| Recommended tyres | 35–40 cali |
| Track increase | 15–20 cm na stronę (wartość zależy od modelu auta) |
| Component | Material |
|---|---|
| Obudowa i pokrywa | aluminium kute serii 7000 |
| Zębatki | stal 20CrMoTi |
| Główka wału | stal 40Cr |
| Półoś | stal 40Cr |
| Łańcuch | stal 50Cr-V |
Track width grows by 15–20 cm per side. That changes the vehicle's outline, and with it what the registration document says. Check what that means in your country before ordering — we cannot settle it for you.
What the kit contains
The kit differs per vehicle model — below is what it is made of.
- mosty portalowe (4 szt.)
- tarcze hamulcowe przednie i tylne
- zaciski tylne
- tylne półosie
- przewody hamulcowe
- przewody ABS
- linki hamulca ręcznego
- wsporniki wzmacniające
- przewód odpowietrzający
ZeonTek fabricated axle
The other route: instead of portals, a stronger axle for heavier loads.
| Parameter | Value |
|---|---|
| Axle tube | średnica 100 mm, ścianka 10 mm |
| Third member | aluminium obrabiane CNC, obróbka cieplna próżniowa |
| Strength analysis | ANSYS Mechanical — siła pionowa, boczna, napędowa i hamowania |
| Stated fitment | Jeep JL i JT |
- korpus pod spawanie DIY, także 6x6 i pod mosty portalowe
- most pełnopływający
- konfigurowalna szerokość
- blokada pneumatyczna albo elektryczna
- piasty ośmiootworowe
Frequently asked questions
Can a portal axle be registered for road use?
The manufacturer claims no type approval — neither TÜV nor ECE. So we cannot say it „is legal”, because that would be an assurance nobody has issued.
What we can state is the technical fact: track width grows by 15–20 cm per side, and that changes the vehicle outline recorded in the registration document. What follows from that in your country is for the testing station and the registration office to decide — check it before you spend the money.
Which vehicles does TRE build portals for?
The manufacturer publishes no model list. Its material shows an example kit for a Suzuki Jimny with a 4-inch lift and notes that „the kits for each car model are different”.
So we keep no ready-made list for portals — every enquiry goes to the manufacturer with a specific vehicle attached.
What is in the kit?
Four portal axles, front and rear brake discs, rear calipers, rear half-shafts, brake and ABS lines, handbrake cables, reinforcing brackets and a breather line. The exact content depends on the vehicle.
The manufacturer states neither kit weights nor permissible loads. We are not going to guess them.
What about central tyre inflation?
The manufacturer states that TRE portal axles can be combined with a central tyre inflation system (CTIS). It gives no technical detail and no list of compatible systems, so we will not go further than that statement.
Portals are a project, not a purchase
Before we can quote, we need the vehicle, the tyre size you plan and whether you already have a lift. Write to us and we will go through it step by step.