RJLeagles2010
New member
A long time ago while looking at the rear axel I wondered why someone had not found a way to move all that up and out of the way. Well I found the information and thought it might be worth sharing. Does anyone here have this on their T4R and if so pictures would be greatly appreciated. Dedicated off road rigs might be the only ones to benefit from this.
Here is a little information I dug up from Dynatrac.
"So what is the advantage of a portal axle? The gear reduction at the hub moves the axle center line up five inches for increased ground clearance. This is a dramatic change; the equivalent of switching from 35” to 44” tires on your vehicle. Additionally, the geared hub design provides a 1.5:1 gearing reduction through a massive 41 spline axle shaft designed specifically to account for increased torque loads. The nodular iron AIM portal gear boxes contain four 2.25 inch wide 8620 heat treated steel gears: a drive gear, two idler gears, and a gigantic driven gear that keeps the drive direction constant, making them a practical retrofit to traditional axle housings. By multiplying torque at the wheel, less torque is transferred through the driveshafts, transfer case, and other upstream drivetrain components. And a numerically higher gear ratio can also now be used, which results in a larger, stronger pinion gear.
The idea of using portal axles for more ground clearance is not new, however there have been a number of factors that have made them unfeasible… until now. In the past you had to overcome poorly functioning drum brakes, long pinions that result in short driveline lengths, excessive weight, and difficult to source foreign parts when trying to retrofit portal axles to your Jeep or 4x4. Dynatrac has worked closely with AIM and Mopar to address all of these issues (and more) with the introduction of their innovative new portal complete axle assemblies and sub-assembly components.
Realistically these new portal axles aren’t for everyone. They are not recommended for highway use, and the leverage of the portal design places additional stress on suspension mounting points and control arms. Electronic controls such as ESP and ABS cannot be retained with the portal boxes, as they can with Dynatrac’s traditional ProRock, Pro, and Trail Series axles. There is no provision for a standard parking brake; however a driveline brake at the transfer case can easily be added to address this issue. Final suspension design will be determined by many factors and it is crucial that the suspension design address the added torque and leverage of the portal system. The end user will need to design proper steering and a strong 4-link suspension. Therefore, it’s important that a qualified specialist with fabrication skills and a thorough knowledge of suspensions install it. In short, this isn’t a ‘turn-key’ assembly that fits any application. With the caveats out of the way, it becomes clear that if you require the absolute greatest ground clearance, with gear reduction to overcome the most severe, boulder-strewn trails and obstacles, there is no substitute for Dynatrac and Mopar axles equipped with AIM portal housings.
The portal wheel ends are currently available for king pin steering knuckles and full floating rear Dana 60, Dana 70, and AAM 14-Bolt applications. Dynatrac can provide the AIM portal housings on their proprietary ProRock and Pro-series axle assemblies with suspension brackets for a wide variety of vehicle applications" (Dynatrac - Confidence to Explore®).
Here is a little information I dug up from Dynatrac.
"So what is the advantage of a portal axle? The gear reduction at the hub moves the axle center line up five inches for increased ground clearance. This is a dramatic change; the equivalent of switching from 35” to 44” tires on your vehicle. Additionally, the geared hub design provides a 1.5:1 gearing reduction through a massive 41 spline axle shaft designed specifically to account for increased torque loads. The nodular iron AIM portal gear boxes contain four 2.25 inch wide 8620 heat treated steel gears: a drive gear, two idler gears, and a gigantic driven gear that keeps the drive direction constant, making them a practical retrofit to traditional axle housings. By multiplying torque at the wheel, less torque is transferred through the driveshafts, transfer case, and other upstream drivetrain components. And a numerically higher gear ratio can also now be used, which results in a larger, stronger pinion gear.
The idea of using portal axles for more ground clearance is not new, however there have been a number of factors that have made them unfeasible… until now. In the past you had to overcome poorly functioning drum brakes, long pinions that result in short driveline lengths, excessive weight, and difficult to source foreign parts when trying to retrofit portal axles to your Jeep or 4x4. Dynatrac has worked closely with AIM and Mopar to address all of these issues (and more) with the introduction of their innovative new portal complete axle assemblies and sub-assembly components.
Realistically these new portal axles aren’t for everyone. They are not recommended for highway use, and the leverage of the portal design places additional stress on suspension mounting points and control arms. Electronic controls such as ESP and ABS cannot be retained with the portal boxes, as they can with Dynatrac’s traditional ProRock, Pro, and Trail Series axles. There is no provision for a standard parking brake; however a driveline brake at the transfer case can easily be added to address this issue. Final suspension design will be determined by many factors and it is crucial that the suspension design address the added torque and leverage of the portal system. The end user will need to design proper steering and a strong 4-link suspension. Therefore, it’s important that a qualified specialist with fabrication skills and a thorough knowledge of suspensions install it. In short, this isn’t a ‘turn-key’ assembly that fits any application. With the caveats out of the way, it becomes clear that if you require the absolute greatest ground clearance, with gear reduction to overcome the most severe, boulder-strewn trails and obstacles, there is no substitute for Dynatrac and Mopar axles equipped with AIM portal housings.
The portal wheel ends are currently available for king pin steering knuckles and full floating rear Dana 60, Dana 70, and AAM 14-Bolt applications. Dynatrac can provide the AIM portal housings on their proprietary ProRock and Pro-series axle assemblies with suspension brackets for a wide variety of vehicle applications" (Dynatrac - Confidence to Explore®).
