GDP Portal Gear Lift FAQ

GDP Portal Gear Lifts give you a lift and a gear reduction in one kit. They’re different from standard suspension lifts because they lift your machine at the hub instead of at the shock—everything gets lifted from the ball joints to the A-arms and frame. A portal gear lift kit is made up of 4 portal boxes that replace your stock hub. They use gears in the box to lower your axle line and provide a gear reduction.

The gear reduction makes it easier bigger, heavier tires and can lower the strain on your drivetrain.

Portals are best for riders who want maximum ground clearance, big tires, and more torque for tough terrain like mud, rocks, or deep ruts. They’re ideal if you frequently ride in conditions where a stock or traditionally lifted machine would get stuck because of poor clearance or lack of torque.

If you prioritize top speed, tight trail width, or racing, portals may not be the best fit due to added width and lower top speed.

At the same time, we offer gear reductions as low as 15% that will boost your low-end grunt without sacrificing much of your top-end speed.

We offer 4”, 6” and 8” portals.

The size you want depends on how much ground clearance you want (obviously) and what gear reduction you need.

• 4” portals: Best for trail riders who want moderate clearance without drastically changing handling or reducing top speed.
• 6” portals: A balanced option for mixed riding—more clearance and torque from larger gear reductions for mud, rocks, and other obstacles.
• 8” portals: Built for extreme riding—maximum lift, huge tires, and deep mud performance. They also come with the biggest gear reductions: 45%, 60%, and 70%.

The bigger the portal, the more ground clearance you get, the bigger tires you can fit, and the bigger gear reductions you can choose. But bigger also means more overall weight and cost.

Whether you get cast or billet is a matter of personal preference. Billet is much stronger and has a nice machined-finish look. Our cast aluminum housings cost less and are designed to be strong enough to handle high-torque and hard riding as well.

Weight differences are minimal between the two materials as well.

Either way, you’re getting the exact same components and performance, just with different housing materials.

We offer 15%, 30%, 45%, 60%, and 70% gear reductions for GDP Portal Gear Lifts.

You can get 15% and 30% reductions in our 4” portals, 30% and 45% in our 6” portals, and 45%, 60%, and 70% in our 8” portals.

Big gear reductions will feel very powerful at the low end. You’ll notice your engine revving up more at low speed to deliver more torque to your tires. Whether you’re running massive tires or not, a big gear reduction will turn them easily through and over virtually any obstacle. You will notice less speed at higher RPM.

15% gear reduction: Keeps higher top speed while providing low-end acceleration—best for trail and general riding, and it’s good for minor tire size increases.

A 15% gear reduction feels like a modest boost when you hit the gas, and you might not notice any performance loss at high speed.

30% gear reduction: Balanced power and speed—good for most riders and mixed terrain who run bigger tires.

A 30% gear reduction feels like a big boost in torque when you hit the gas. You will notice that RPMs will be higher as speed increases, and you won’t be able to reach your factory top speed (assuming your tire size remains the same).

45%, 60%, 70% gear reductions: Maximum torque—ideal for turning large tires and tackling deep mud. The gear reduction you get here really depends on just how big your tires are and how dedicated you are to pure mudding.

Many of our GDP Portals have the option for a dual-idler configuration.

Every hub has a drive gear (where the axle goes in), an idler gear, and a driven gear (that connects to your wheel hub). That means all the power transfers through the idler gear, and the best way to make that part of the chain stronger is to add a second idler gear to share the load. That’s what our dual-idler configurations do—they share the load going through the portal hub to help prevent idler failure.

Our dual idlers are precisely finished and mated. The precision of these dual-idler gears is important because even a little bit of slop causes one idler gear to do most of the work, which defeats the purpose of the dual idlers. Ours share the load as evenly as possible.

No. Each housing is designed for a specific gear reduction to ensure ideal gear mating and maximize strength. To change the gear reduction, you’d have to change housings too.

Portals are a little different from traditional lifts, so here are the biggest surprises you might not be expecting:

• Portals add about 4” of width to each side of your machine, which makes your vehicle about 8” wider overall. That can make tight trails more difficult but improves stability and clearance overall.
• Portals require more maintenance than other lifts, including gear oil checks and replacement. They’re just like any other gear-driven component on your machine.
• Higher gear reductions may reduce top speed. If you increase your tire size along with your gear reduction, you can just about retain your top speed spec.

Use only non-synthetic, non-detergent 80W-90 gear oil. You can find it at your local auto parts store.

Our Portal Blood Gear Oil is specially formulated for our GDP portals to last longer and lubricate better than your average gear oil.

You need approximately 1 qt or less to fill an entire set of portals regardless of your size or gear ratio. Fill each box to just below the fill hole. The amount in each box will vary slightly depending on your specific kit.

We recommend changing your gear oil at least annually, but you should check it regularly. If you ride in mud or water, you need to check your oil after every ride and change it immediately if it’s milky or discolored. If mud or water has gotten into your box, it can corrode bearings and gears over time. Discoloration can also indicate potential damage to your seals or gaskets.

Checking your oil before every ride to make sure you’ve still got enough is a good idea. If you’re losing oil, that’s another sign that you’ve damaged a seal somewhere. And you don’t want to ride with a damaged seal.

Internal bearings should be inspected annually for damage and corrosion. That means opening up your box, getting a good look at each one, and making sure your internals are clean. If there’s rust or damage, it’s time to replace them. We sell complete bearing and seal kits for all our portals.

If you see discoloration when you’re checking your oil, that’s a sign that you should inspect and clean your bearings as well.

Leaving bearings unchanged when contaminated with anything other than oil can lead to major damage to the bearing, gears, and box itself.

If you keep a good eye on your oil and make sure you keep things clean, your annual maintenance cost should equal the price for a quart of 80W-90 gear oil—about $15–$30. Most people who check and change their oil regularly never have to change a bearing or seal. Even if you replace a bearing or two over the course of a few years, you’re looking at around $100 a year on average.

There are a few things to look out for. If you see any of these indicators, you should take action immediately to avoid bigger problems.

• Milky or cloudy oil: Milky-looking oil can indicate water intrusion. You should change the oil and inspect your seals.
• Low oil level: If you notice your oil levels are low, that may point to a leaking seal or gasket. Check oil levels regularly and look for visible leaks on the outside of boxes. Dust sticks to leaking oil and is easier to spot than an oil leak on a clean portal box.
• Unusual noises (grinding, whining, clicking): New sounds can be caused by low or contaminated oil. Change your oil, refill, and check for leaks.
• Excessive heat at the portal housing: The main cause of heat is low oil or poor-quality gear oil. Ensure your housings are filled with high-quality gear oil like Portal Blood.

Gen 1, Gen 2, and Gen 3 refer to which version of GDP Portal Gear Lifts. When we make a major design change, we also change the name. Gen 3 has billet and cast aluminum housing options, a stronger housing design, the option to choose your gear reduction, stronger gear materials, and sealed drive gears along with other changes.

Gen 2 had a much bigger output shaft than gen 1 and stronger caliper mounts, lids, and rotor hub. All which carried forward and was improved for Gen 3.

Gen 1 was the original GDP Portal Gear Lift.

We only sell Gen 3 portals currently.

Gen 1 portals were sold before October 2017. They have a smaller output shaft (the splined section has a much smaller diameter than the smooth section of the shaft), and they use a tapered washer behind the hubs.

Gen 2 portals were sold between October 2017 and January 2019, and they use a large output shaft (the splined section has almost the same diameter as the smooth section of the shaft), and there is no marking on the housing to indicate gear reduction.

Gen 3 uses the same large shaft as Gen 2 but also has an engraved 15, 30, or 45 on the housing near the drain plug and under the caliper mounting location. They also have a 3-bolt cap instead of a 4-bolt cap like Gen 1 and 2, and they use diff-style drain plugs with O-ring seals. GDP 8” Portal Gear Lifts and billet aluminum portals are all Gen 3.

If you’re unsure of what you have, give us a call at 855-743-3427.

Every machine is different, but some CV cups will not touch the back of the box. Can-Am vehicles in particular leave a larger gap between the back of the box and the CV cup. This is normal and will not affect performance or longevity.

We sell conversion kits to make any set of portals compatible with a variety of UTVs and ATVs. Basically, if we sell a portal for a certain vehicle on SuperATV.com, we can sell you a conversion kit to make whatever portals you have fit that certain vehicle.

What you need depends on what you’re converting from and what you’re converting to. A RZR to another RZR? Probably just need new backing plates. A Ranger to an X3? You’re gonna need a bit more to make that work.

Give us a call at 855-743-3427 to get the one you need.

Yes! This is the best part about portal gear lifts—the ability to lift, and lift again! Because portals lift your machine at the hub, it doesn’t change your suspension geometry. Just install your lift and your portals at the same time and you’ll be in the barrel club.

We sell conversion kits to upgrade 4” Gen 1 portals to Gen 2 only. We do not offer conversion kits for any other lift size or generation.

If it breaks and it’s our fault, we’ll take care of it. If it breaks and it’s your fault, you’ll take care of it, but we’ll do our best to get you up and running again. We stand by our products and want to see them in good working condition out on the trail.

This is outlined in our limited lifetime warranty section on every GDP Portal Gear Lift page. Basically, we don’t cover wear items like bearings, seals, and gaskets, and it’s up to our discretion to decide if your portals were neglected or abused. Examples of this would be not putting oil in your boxes or putting grease instead of oil. If you try to use your portal for something other than riding like some kind of weird power take-off and it breaks, we might not cover that.

Normal maintenance and servicing won’t void your warranty even if you decide to buy matching seals from an auto parts store instead of buying them from us. Disassembling it for a deep clean is also OK—just make sure you get it put back together properly. And don’t replace the gears with other gears. We spent a lot of time and effort making them as good as possible. Using someone else’s gears is a bad idea.

Keep your usage and repairs within the scope of the portal gear lift’s intended function, and you won’t have any trouble if you need to warranty.

We love keeping our portals running, and we’re super easy to work with. Give us a call at 855-743-3427 if you have any issue with your GDP Portals.

The unique rear wheel hub on the older Outlander and Commander models make it impossible to mount our portal gear boxes. We include rear trailing arms for those vehicles to provide a robust and secure mounting location.

Although we estimate a 10 hour install time for the average person, the individual steps to complete installation are relatively simple. It’s not as hard as cracking open a transmission and changing gears, but it’s tougher than changing a diff. We have detailed, full-color instructions as well as a helpful installation video to make it as easy as possible.

We’re here to help you with any part of your installation. Just give us a call at 855-743-3427.

We’ve sold thousands of GDP Portal Gear Lifts and made hundreds of thousands of weekends better. What makes ours the most used portal gear lifts in the UTV/ATV industry?

Here’s what we’ve got that no one else does:

• Precision ground gears—for better mating, less heat, and quiet running
• 9310 steel alloy gears—one of the strongest gear materials around
• 15%, 30%, 45%, 60%, and 70% gear reductions—get the gear reduction that matches your ride style
• 4”, 6”, and 8” portal lifts—get the lift you want, whether that’s modest or really (really) big
• Sealed drive gear—it helps prevent oil leaks where your axle goes in
• Thrust bearing—built to withstand huge loads on your output shaft
• Billet and cast aluminum boxes—you can choose the box that meets your needs
• Strong backing plate—we use a high-strength steel alloy that’s stronger than chromoly to make sure your A-arms stay attached to your portal box
• Leak-resistant gaskets, seals, and plugs—we know what these boxes need, and we use the right stuff