Portal axles

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I wheel with a guy that has a humvee . The thing is huge and he can’t do all the trails we can but it holds it’s own if the trail is wide enough. We're planning a trip to Moab next year. I can let you know how it proforms in the rocks then.

You would also think with it being 8 feet wide there would be alot of space inside, It's not. where you ride is small, it's loud, and uncomfortable.
The local group I go with wheel pretty much anything, Even a Honda Del sol

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Sorry to resurrect an old thread, but I have been watching videos online about portal axles. It seems that if you want to serious 4x4 with great clearance, then you will need portal axles. It was only a distant thought and I was just thinking of doing a 2" lift to my Ram 1500 with some other modifications light mods for touring.

And then I saw this Brabus Truck & this video


I would like to turn my Ram into a something like this. It is my forever truck. So I think the cost is worth it. Although I can't seem to find any bolt on kits for IFS trucks.
 

Dukestaco

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Sorry to resurrect an old thread, but I have been watching videos online about portal axles. It seems that if you want to serious 4x4 with great clearance, then you will need portal axles. It was only a distant thought and I was just thinking of doing a 2" lift to my Ram 1500 with some other modifications light mods for touring.

And then I saw this Brabus Truck & this video


I would like to turn my Ram into a something like this. It is my forever truck. So I think the cost is worth it. Although I can't seem to find any bolt on kits for IFS trucks.
If you can find the parts to make it happen that would be cool as hell. I couldn't watch the video though. 5 seconds in I had to mute it. Couldn't stand the guys voice. 2 minutes in and I stopped all together. That guys hands are probably so soft and supple that he would be an inmates best friend.
 
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Well once when I was driving home from work, there was a vehicle transport taking 3 toyota Hilux pickups. Now I'm not a huge fan of Toyotas, but these trucks were all blacked out and stuff, and they looked like the Brabus with wide arches, roof-rack, etc. But they didn't have portals. That was my goal for my Ram, until I saw the Brabus.

I honestly don't know why portals aren't as big in the offroading community, especially with the IFS trucks. If they're good enough for the military, should be good enough for us. However most of the comments are negative and mostly about it being more maintenance, costly and not worth the effort.

I do get that when you watch videos like the one above, you do think that maybe portals are a bit of overkill. But seriously, I still have my heart set on making my own version of the Brabus truck.
 
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Buy an old unimog and use those parts, then sell the remains.
Sounds like a good idea. Isn't the Unimog a solid axle vehicle? I am hoping to keep the IFS on the Ram 1500.

I think that there are companies like Tibus-offroading that have bolt on kits. But again those are just for solid axle vehicles.

I did find a Russian video where these guys did a portal conversion on an IFS Pajero Sport.

Marks 4WD did portals for the Tonka Hilux.

 

Arcticelf

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Well once when I was driving home from work, there was a vehicle transport taking 3 toyota Hilux pickups. Now I'm not a huge fan of Toyotas, but these trucks were all blacked out and stuff, and they looked like the Brabus with wide arches, roof-rack, etc. But they didn't have portals. That was my goal for my Ram, until I saw the Brabus.

I honestly don't know why portals aren't as big in the offroading community, especially with the IFS trucks. If they're good enough for the military, should be good enough for us. However most of the comments are negative and mostly about it being more maintenance, costly and not worth the effort.

I do get that when you watch videos like the one above, you do think that maybe portals are a bit of overkill. But seriously, I still have my heart set on making my own version of the Brabus truck.

Portals are used by the military, and they are tough as hell, but they are also really expensive (military doesn't care) limit top speed (military doesn't care) and make the best all-around off roader (military does care).

How many of us will wheel deep mud, rocks, rutted tracks, and highspeed desert all on the regular? More likely each of us has one style of wheeling we mostly do, and build rigs for that.

All that said: you should build a rig with portals and wheel the shit out of it, that would be an absolutely cool build.
 

Slim-Whitey

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Fun fact, the 2015+ G Wagen is offered in a 4×4² model with portals nicked off the G63 6x6.

It's nuts, and whatever they do to it, the portals don't seem to reduce the speeds much.

You can buy a kit to convert standard G wagon axles for 20g. :rofl:
 
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Fun fact, the 2015+ G Wagen is offered in a 4×4² model with portals nicked off the G63 6x6.

It's nuts, and whatever they do to it, the portals don't seem to reduce the speeds much.

You can buy a kit to convert standard G wagon axles for 20g. :rofl:
Yeah.. there are portal kits from Tibus in Germany. But they are all for solid axle vehicles. Haven't found one for IFS vehicles yet.

I wish I could ask Brabus where they got the portals for their G63 XLP.
Maybe I'll shoot them an email and see if they will answer.
 

AssBurns

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If you have deep pockets, give 74weld a call. They make portals for IFS and SA.
https://www.fourwheeler.com/how-to/...t-kit-and-lower-gearing-all-wrapped-into-one/
Well... the idea of portal axles doesn't run cheap and my pockets are shallow. But we are talking about a dream truck build. And honestly, rather that spending money on a standard lift, I could just save it up and put it towards getting a portal kit made.

From what I am seeing on their site, they base their kit on Unimog portals, which is not a bad start. The design of those portals have served the Unimog reliably for decades.
However it would appear that their gear ratio is 1.55:1.

Marks4wd in Australia makes a portal kits for solid axle Land Cruisers and Nissan Patrols which are 1.16:1. They say they do this ratio to sort of come close to the stock gearing of the vehicles.

I'm not really sure which is better. Can anyone explain the gearing numbers to me?
 

Slim-Whitey

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It's just another final drive.

So running 1.55:1 in the portal, with, say, 3:1 in the diff, gives the same final gearing to the wheels as running 4.65:1 in the axle.

The shorter gearing in the portal allows you to run taller gearing in the axle. Taller axle gears increase the size of the pinion head and increase the surface area of the meshed teeth at any given point. This significantly increases the strength of the hypoid set.
For instance, a 3.07 gearset in a D44 uses a massive pinion head compared to a 4.88 gearset.

The portals don't run hypoid gears, and being in a closer ratio have nearly ideal engagement anyway. So running a 1.5 in the portal allows a much smaller hypoid set to be used in the diff, allowing a smaller pumpkin, better ground clearance, and still retaining a strong differential.
 

AssBurns

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What he said ^^^^

Basically, the higher the gear ratio typically means weaker gear sets in the differential. So instead of running 5.29 gears to get the desired final drive ratio, you can run 3.41 (or whatever is similar and available) plus 1.55:1 in the portals to achieve the same final drive ratio.
 
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OK.. So it all depends on what kind of axle ratio you have?
My truck is a 2014 Ram 1500 SLT, with a Hemi V8 and 8 Speed transmission. I understand that the rear axle is 3.21. So what would the 1.55:1 portals do to that?
 

Slim-Whitey

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Multiply 3.21 X1 .55

Same as running 4.97 axle gears.

Think of them as another gear. If you set them up opposite to what they are, they'd be an overdrive gear.
 
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Multiply 3.21 X1 .55

Same as running 4.97 axle gears.

Think of them as another gear. If you set them up opposite to what they are, they'd be an overdrive gear.
So as I understand it, means an increase in torque to the wheels at a higher transmission gear?
 

Slim-Whitey

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In all gears.

Anything that isn't a transmission gear multiplies torque in all gears it is used in. A transmission gear only mutiplies torque when it has power passing through it (obviously)

So, if your engine is making 100ftlb at the crank, it goes like this:

Engine X transmission gear X transfer case gear X final drive

With a portal, it'd look like this:

Engine X transmission gear X transfer case gear X final drive x portal

So, with typical t case, axle, and trans gears, in first gear,
100 x 5.5 x 2.73 x 4.1= 6156ftlb. In first gear, lo range.

Adding a 1.55 portal to that makes it 9542ftlb.

If you want to keep your 6156ftlb in low range, first gear, but increase the strength of your differential gear set, you can divide your gear ratio (4.1) by your new portal ratio (1.55), and use the gearset closest to that value, (2.65).
Going to a 2.65 set from a 4.10 set would see a huge increase in diff gear strength.

A numerically higher portal ratio is better than a lower one, until you hit a point where the mesh of the spur or helical gears in the portal is weaker than the strength gain in the differential gears.
 
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@Slim-Whitey Thank you for all the information. What does all of that do for the ride on the highway, cruising at 120kph? The truck is my daily and I often do 30 minute stints on the highway at that speed.
 

Slim-Whitey

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Well the ride won't change. Your suspension hasn't changed, neither has your steering geometry.

Your fuel economy will go down because the truck is taller. No way around that.

I'd check with the kit mfg for what speeds they are capable of. Different setups are good for different speeds.

Overall, just to get a 4" or whatever lift, portals are a terrible way to accomplish it. They have a distinct benefit, but for the 20G you're looking at spending, you can build one bitch of a rig.
 
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