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Clarke1791

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Just got back from Moab and time to give an honest assessment on this somewhat controversial/debated upgrade. People have a tendency to abstain from saying anything bad after spending such a crazy amount of money on an accessory, but that’s not me and I owe nothing to 74Weld. No notes were taken real time so this will mostly be a rambling of words as they’re thought of. I’ll try to keep the different topics separated.

Drove on the interstate at mostly 85ish mph and of course there is no gear noise despite what @tmason10 tries to claim about straight cut gears in portals. We have zero CEL’s and adaptive cruise/lane assist still work without issue. Checked temps on the first fuel up after about two hours of driving. Rear portals at 160F rear diff at 192F. Front portals 91F front diff (32 spline spicer) 212F. All running new Maxima full synthetic oil. 75W140 in differentials as recommended by Dana. 75W90 in portals to 74Weld spec. Fuel economy on 40” Toyo Open Country MT at 30 psi 12.2 mpg. Increased to 14 mpg for the rest of the trip. Cruising RPM might be 2400 with the ten speed auto.

On the trail you will absolutely crawl in 4L M1. It’s fantastic. The clearance is ridiculous as anyone would expect. All the benefits that anyone has ever mentioned are very real so we’ll focus on…maybe not “negatives”…but things we learned. The first big thing we probably all realize is the vast increase in scrub radius. Pushing that 110 pound 40” tire at seven psi plus wheel plus beadlocks plus portal out 3.5” away from the pivot points is a lot for the steering rack to move. It wasn’t unexpected that there would be times the rack wouldn’t be able to keep up, but it did happen more often than we would’ve liked. Definitely need to plan the lines out where the steering can be done while moving as often as possible. Continuing the scrub radius discussion, the toe-in under droop is further exaggerated by the extension of the portals. This is made even worse with a yoke for heims rather than the Ford ball joints.

I’ll include a pixelated close up from Hells Gate where passenger tire is straight but driver is toed in under full droop. I thought maybe we knocked the alignment way off on high dive and I just hadn’t noticed it, but after she got to the top I measured it out and it’s fine. Another interesting observation is that this combination of IFS and huge scrub radius made it very important to be smooth with throttle control and braking modulation. Sudden lifting of the front from throttle or diving under braking can cause a deviation from the planned line whereas under the same scenarios it wasn’t an issue on rigs equipped with a long travel suspension. Mrs. Sierra Bronco has a newfound ambition to become proficient with two footed driving and pushing through the brakes. Will also do more experimenting with the one pedal driving option to see if that is better than what humans can accomplish. We’re definitely happy that our Wildtrak has rock crawl mode to help with throttle response, but driving skills will be improved on as well.



Also when planning lines it’s important to note the additional clearance will make the rig behave differently compared to similar builds without portals. We reached out to a local that is also a guide and Bronco Offroadeo instructor as we hadn’t done Cliffhanger or Pritchett before and wanted an experienced person with us. This wasn’t his first Bronco on 40’s, but it was the first one with portals. On the way down from Cliffhanger there’s an optional obstacle where you pivot your rockslider off of a rock to straighten up with the drop. Ours started to pivot, then popped up over the rock and hoo lawdy was it close to rolling. He was beating himself up on what happened when we pointed out we’re likely 4” higher on the frame compared to the other rigs, with UHMW skids, and our body mounted sliders are 1.5” higher due to the body lift. Then it all made sense. Lesson learned.



Reliability wasn’t an issue. The Bronco took some massive hits on the front end but luckily all the LCA mounts had been strengthened and we also welded on double shear UCA mounts. The front passenger corner basically took the full 6100 pounds from a five foot drop (slide) with the tire turned and while metals were likely fatigued, nothing bent or broke. Not sure if the one ton bearing packs and lugs would’ve made a difference over what the other portal options come with, but it was certainly nice knowing they were beefy as hell. Don’t forget the steering knuckles. Or 1” shafts from the RK coilovers.



In summary, we found a lot of things we can improve on with our driving and spotting now that we have an idea of how the portals affect vehicle behaviors when wheeling. The effects of scrub radius increase makes sense when you think about it after the fact, we just didn’t anticipate it at the time.


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Clarke1791

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Just got back from Moab and time to give an honest assessment on this somewhat controversial/debated upgrade. People have a tendency to abstain from saying anything bad after spending such a crazy amount of money on an accessory, but that’s not me and I owe nothing to 74Weld. No notes were taken real time so this will mostly be a rambling of words as they’re thought of. I’ll try to keep the different topics separated.

Drove on the interstate at mostly 85ish mph and of course there is no gear noise despite what @tmason10 tries to claim about straight cut gears in portals. We have zero CEL’s and adaptive cruise/lane assist still work without issue. Checked temps on the first fuel up after about two hours of driving. Rear portals at 160F rear diff at 192F. Front portals 91F front diff (32 spline spicer) 212F. All running new Maxima full synthetic oil. 75W140 in differentials as recommended by Dana. 75W90 in portals to 74Weld spec. Fuel economy on 40” Toyo Open Country MT at 30 psi 12.2 mpg. Increased to 14 mpg for the rest of the trip. Cruising RPM might be 2400 with the ten speed auto.

On the trail you will absolutely crawl in 4L M1. It’s fantastic. The clearance is ridiculous as anyone would expect. All the benefits that anyone has ever mentioned are very real so we’ll focus on…maybe not “negatives”…but things we learned. The first big thing we probably all realize is the vast increase in scrub radius. Pushing that 110 pound 40” tire at seven psi plus wheel plus beadlocks plus portal out 3.5” away from the pivot points is a lot for the steering rack to move. It wasn’t unexpected that there would be times the rack wouldn’t be able to keep up, but it did happen more often than we would’ve liked. Definitely need to plan the lines out where the steering can be done while moving as often as possible. Continuing the scrub radius discussion, the toe-in under droop is further exaggerated by the extension of the portals. This is made even worse with a yoke for heims rather than the Ford ball joints.

I’ll include a pixelated close up from Hells Gate where passenger tire is straight but driver is toed in under full droop. I thought maybe we knocked the alignment way off on high dive and I just hadn’t noticed it, but after she got to the top I measured it out and it’s fine. Another interesting observation is that this combination of IFS and huge scrub radius made it very important to be smooth with throttle control and braking modulation. Sudden lifting of the front from throttle or diving under braking can cause a deviation from the planned line whereas under the same scenarios it wasn’t an issue on rigs equipped with a long travel suspension. Mrs. Sierra Bronco has a newfound ambition to become proficient with two footed driving and pushing through the brakes. Will also do more experimenting with the one pedal driving option to see if that is better than what humans can accomplish. We’re definitely happy that our Wildtrak has rock crawl mode to help with throttle response, but driving skills will be improved on as well.



Also when planning lines it’s important to note the additional clearance will make the rig behave differently compared to similar builds without portals. We reached out to a local that is also a guide and Bronco Offroadeo instructor as we hadn’t done Cliffhanger or Pritchett before and wanted an experienced person with us. This wasn’t his first Bronco on 40’s, but it was the first one with portals. On the way down from Cliffhanger there’s an optional obstacle where you pivot your rockslider off of a rock to straighten up with the drop. Ours started to pivot, then popped up over the rock and hoo lawdy was it close to rolling. He was beating himself up on what happened when we pointed out we’re likely 4” higher on the frame compared to the other rigs, with UHMW skids, and our body mounted sliders are 1.5” higher due to the body lift. Then it all made sense. Lesson learned.



Reliability wasn’t an issue. The Bronco took some massive hits on the front end but luckily all the LCA mounts had been strengthened and we also welded on double shear UCA mounts. The front passenger corner basically took the full 6100 pounds from a five foot drop (slide) with the tire turned and while metals were likely fatigued, nothing bent or broke. Not sure if the one ton bearing packs and lugs would’ve made a difference over what the other portal options come with, but it was certainly nice knowing they were beefy as hell. Don’t forget the steering knuckles. Or 1” shafts from the RK coilovers.



In summary, we found a lot of things we can improve on with our driving and spotting now that we have an idea of how the portals affect vehicle behaviors when wheeling. The effects of scrub radius increase makes sense when you think about it after the fact, we just didn’t anticipate it at the time.


IMG_3179.jpeg


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IMG_3088.jpeg


IMG_3006.jpeg


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Thanks for the great post with tons of info. I have a 2 door WT on 74 Weld portals that I not had the opportunity to wheel at all. Hopefully soon.
 
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SierraBronco

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Thanks for the great post with tons of info. I have a 2 door WT on 74 Weld portals that I not had the opportunity to wheel at all. Hopefully soon.
You’re the guy that bought that package from an unknowing dealer right?
 

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Certainly a limitation. Airing up the front will help but not sure to what extent. Will probably drop down to 38’s on the next set of tires
Just for reference I saw a ruby take some serious shit yesterday on MT 37s beadlocks at 7psi and with a little guidance was able to pull it off, none of the built broncos in our group were going to make it. Just dont or at least me have enough front articulation plus I always every time get hung up on the lower trail arms or shock towers when I try to do really big stuff.

Your rig looks like some serious COG challenges. I have been out with a couple broncos with non portals on 38s and 3" body lifts, etc and I swear every time they almost toss it over. I 100% agree knowing your rig and having the "spotting" where it needs to be is absolutely valuable. Enjoy your new mini monster truck :)
 
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Just for reference I saw a ruby take some serious shit yesterday on MT 37s beadlocks at 7psi and with a little guidance was able to pull it off, none of the built broncos in our group were going to make it. Just dont or at least me have enough front articulation plus I always every time get hung up on the lower trail arms or shock towers when I try to do really big stuff.

Your rig looks like some serious COG challenges. I have been out with a couple broncos with non portals on 38s and 3" body lifts, etc and I swear every time they almost toss it over. I 100% agree knowing your rig and having the "spotting" where it needs to be is absolutely valuable. Enjoy your new mini monster truck :)
The COG is definitely a concern. The added width helps with that, but we were trying to keep it lower. We gained more travel with the new coilovers but unfortunately had to bump up the preload (we started at a third of their recommended minimum) to stop bottoming out rather frequently, and that gave us another couple inches of suspension lift. Rides really well even without adjusting the shims, it’s just taller than we want. Next plan will be modifying shock towers to drop it back down a couple inches but maintain available travel.
 

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Just for reference I saw a ruby take some serious shit yesterday on MT 37s beadlocks at 7psi and with a little guidance was able to pull it off, none of the built broncos in our group were going to make it. Just dont or at least me have enough front articulation plus I always every time get hung up on the lower trail arms or shock towers when I try to do really big stuff.

Your rig looks like some serious COG challenges. I have been out with a couple broncos with non portals on 38s and 3" body lifts, etc and I swear every time they almost toss it over. I 100% agree knowing your rig and having the "spotting" where it needs to be is absolutely valuable. Enjoy your new mini monster truck :)
Something else we also wondered about is how much our additional weight in the back helped. Steel bumper, steel frame mounted tire carrier, 40” spare on beadlocks with a pound of balance beads, the air compressor, rear winch, ARB toolbox, and gotta be 100 pounds of tools/recovery gear in there. 🤔🤔
 

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Just got back from Moab and time to give an honest assessment on this somewhat controversial/debated upgrade. People have a tendency to abstain from saying anything bad after spending such a crazy amount of money on an accessory, but that’s not me and I owe nothing to 74Weld. No notes were taken real time so this will mostly be a rambling of words as they’re thought of. I’ll try to keep the different topics separated.

Drove on the interstate at mostly 85ish mph and of course there is no gear noise despite what @tmason10 tries to claim about straight cut gears in portals. We have zero CEL’s and adaptive cruise/lane assist still work without issue. Checked temps on the first fuel up after about two hours of driving. Rear portals at 160F rear diff at 192F. Front portals 91F front diff (32 spline spicer) 212F. All running new Maxima full synthetic oil. 75W140 in differentials as recommended by Dana. 75W90 in portals to 74Weld spec. Fuel economy on 40” Toyo Open Country MT at 30 psi 12.2 mpg. Increased to 14 mpg for the rest of the trip. Cruising RPM might be 2400 with the ten speed auto.

On the trail you will absolutely crawl in 4L M1. It’s fantastic. The clearance is ridiculous as anyone would expect. All the benefits that anyone has ever mentioned are very real so we’ll focus on…maybe not “negatives”…but things we learned. The first big thing we probably all realize is the vast increase in scrub radius. Pushing that 110 pound 40” tire at seven psi plus wheel plus beadlocks plus portal out 3.5” away from the pivot points is a lot for the steering rack to move. It wasn’t unexpected that there would be times the rack wouldn’t be able to keep up, but it did happen more often than we would’ve liked. Definitely need to plan the lines out where the steering can be done while moving as often as possible. Continuing the scrub radius discussion, the toe-in under droop is further exaggerated by the extension of the portals. This is made even worse with a yoke for heims rather than the Ford ball joints.

I’ll include a pixelated close up from Hells Gate where passenger tire is straight but driver is toed in under full droop. I thought maybe we knocked the alignment way off on high dive and I just hadn’t noticed it, but after she got to the top I measured it out and it’s fine. Another interesting observation is that this combination of IFS and huge scrub radius made it very important to be smooth with throttle control and braking modulation. Sudden lifting of the front from throttle or diving under braking can cause a deviation from the planned line whereas under the same scenarios it wasn’t an issue on rigs equipped with a long travel suspension. Mrs. Sierra Bronco has a newfound ambition to become proficient with two footed driving and pushing through the brakes. Will also do more experimenting with the one pedal driving option to see if that is better than what humans can accomplish. We’re definitely happy that our Wildtrak has rock crawl mode to help with throttle response, but driving skills will be improved on as well.



Also when planning lines it’s important to note the additional clearance will make the rig behave differently compared to similar builds without portals. We reached out to a local that is also a guide and Bronco Offroadeo instructor as we hadn’t done Cliffhanger or Pritchett before and wanted an experienced person with us. This wasn’t his first Bronco on 40’s, but it was the first one with portals. On the way down from Cliffhanger there’s an optional obstacle where you pivot your rockslider off of a rock to straighten up with the drop. Ours started to pivot, then popped up over the rock and hoo lawdy was it close to rolling. He was beating himself up on what happened when we pointed out we’re likely 4” higher on the frame compared to the other rigs, with UHMW skids, and our body mounted sliders are 1.5” higher due to the body lift. Then it all made sense. Lesson learned.



Reliability wasn’t an issue. The Bronco took some massive hits on the front end but luckily all the LCA mounts had been strengthened and we also welded on double shear UCA mounts. The front passenger corner basically took the full 6100 pounds from a five foot drop (slide) with the tire turned and while metals were likely fatigued, nothing bent or broke. Not sure if the one ton bearing packs and lugs would’ve made a difference over what the other portal options come with, but it was certainly nice knowing they were beefy as hell. Don’t forget the steering knuckles. Or 1” shafts from the RK coilovers.



In summary, we found a lot of things we can improve on with our driving and spotting now that we have an idea of how the portals affect vehicle behaviors when wheeling. The effects of scrub radius increase makes sense when you think about it after the fact, we just didn’t anticipate it at the time.


IMG_3179.webp


IMG_3159.jpeg


IMG_3088.jpeg


IMG_3006.jpeg


IMG_2998.jpeg


IMG_2951.jpeg


IMG_2934.jpeg


IMG_2802.jpeg


IMG_2920.webp


IMG_2927.jpeg


IMG_2897.jpeg


IMG_2143.jpeg
Great review and observations! I am saving pennies for portals, but I believe I will stick with 37s/38s. I have reservations at a place for May next year - can't wait. I won't have my Bronco, but will rent a jeep for a few days. Taking a couple of guys from work who have never been...

You definitely need to go back and do Pritchett - my favoritest trail in Moab. Also, looks like you did Moab Rim which is another favorite. Did you take the short hike to see the petroglyphs at the top? High Dive is always good for a pucker. I'm surprised you had any issues with Upchuck. With your clearance, you should have been able to put your tire in the crack and power up???
 
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Great review and observations! I am saving pennies for portals, but I believe I will stick with 37s/38s. I have reservations at a place for May next year - can't wait. I won't have my Bronco, but will rent a jeep for a few days. Taking a couple of guys from work who have never been...

You definitely need to go back and do Pritchett - my favoritest triail in Moab. Also, looks like you did Moab Rim which is another favorite. Did you take the short hike to see the petroglyphs at the top? High Dive is always good for a pucker. I'm surprised you had any issues with Upchuck. With your clearance, you should have been able to put your tire in the crack and power up???
I think we could’ve done Pritchett successfully, but it would’ve been pretty nerve wracking. She was getting better with the throttle towards the end of the trip but wasn’t quite comfortable with taking on Pritchett just yet. Prudent decision. The FJ that was with us was struggling a little as well despite long travel, both lockers, and 37’s with beadlocks. Then there was the Rubicon on 35’s with 20’s and no beadlocks. She still wanted to hit Pritchett but man that’s a bad combo for wheel setup. Zero flex in her sidewalls and she’s a heavy throttle applicator whenever it’s not going the way she wants. The local said it had been washed out badly with all the flash flooding and is a completely different trail than what he’s used to. Had just tried running it the previous week with a SXS group and 3/5 of them broke before getting halfway. So all things considered we decided it best to save it for another time after getting better with driving.

If upchuck is coming out of High dive then yeah-it was a pain. Dropped into that crack and initially tried driving out of it but didn’t like the front driver lift and the rear passenger hadn’t dropped in yet, so we backed out and lined it back up.
 

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I think we could’ve done Pritchett successfully, but it would’ve been pretty nerve wracking. She was getting better with the throttle towards the end of the trip but wasn’t quite comfortable with taking on Pritchett just yet. Prudent decision. The FJ that was with us was struggling a little as well despite long travel, both lockers, and 37’s with beadlocks. Then there was the Rubicon on 35’s with 20’s and no beadlocks. She still wanted to hit Pritchett but man that’s a bad combo for wheel setup. Zero flex in her sidewalls and she’s a heavy throttle applicator whenever it’s not going the way she wants. The local said it had been washed out badly with all the flash flooding and is a completely different trail than what he’s used to. Had just tried running it the previous week with a SXS group and 3/5 of them broke before getting halfway. So all things considered we decided it best to save it for another time after getting better with driving.

If upchuck is coming out of High dive then yeah-it was a pain. Dropped into that crack and initially tried driving out of it but didn’t like the front driver lift and the rear passenger hadn’t dropped in yet, so we backed out and lined it back up.
Yes, Upchuck is the obstacle after High Dive. I used to tail gun that trail during Safari, but looks like HD has gotten nastier since I did it last. Back in the day, we used to run Pritchett and then Behind the Rocks backwards rather than taking the long dusty road back to pavement - may not be possible these days unless in a buggy. Did y'all go all the way to White Knuckle? That also has potential high entertainment value :)... I have heard that Pritchett has changed due to flooding - probably a good decision to wait until Mrs. Sierra is more comfortable... The last climb out of the canyon is chock full of obstacles that could ruin your day...
 
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Yes, Upchuck is the obstacle after High Dive. I used to tail gun that trail during Safari, but looks like HD has gotten nastier since I did it last. Back in the day, we used to run Pritchett and then Behind the Rocks backwards rather than taking the long dusty road back to pavement - may not be possible these days unless in a buggy. Did y'all go all the way to White Knuckle? That also has potential high entertainment value :)... I have heard the Pritchett has changed due to flooding - probably a good decision to wait until Mrs. Sierra is more comfortable... The last climb out of the canyon is chock full of obstacles that could ruin your day...
Oh wow. Hitting them both could make for a long day!

We didn’t make it to White Knuckle. Kinda forgot about it until making it passed the dunes and nobody felt like turning around by then
 

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Certainly a limitation. Airing up the front will help but not sure to what extent. Will probably drop down to 38’s on the next set of tires
Out of interest what offset would you do if on 38's and why?
Definitely a necessity, at least if you plan on really working your rig. And even though we made the decision to bail on Pritchett until becoming more proficient with how to drive, we still pushed it. Gonna play around running 12-14 psi on the front tires to give the rack a little help. Leave the rears low at 6-7.

We’ll need to plan a Portal run 👊🏼
so what steering rack would you like to have done, 74weld’s?
 
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Out of interest what offset would you do if on 38's and why?

so what steering rack would you like to have done, 74weld’s?
I’d like to bring them in more regardless of tire size. +55 would be awesome but it’s not going to happen with 17’s and 74Weld portals. 🤷🏼‍♂️

This has the 74Weld billet steering rack and Hoss 3.0 guts. If a better/stronger option exists at the moment I’m not familiar with it. The local that was with us was understandably going crazy when it wouldn’t steer 😂
 

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Out of interest what offset would you do if on 38's and why?
King pin axis is about 20 degrees from vertical. So roughly 10-15 mm of offset for every inch of height gain. So 30 mm offset for 35s, 15-20 mm for 37-38, and 0 mm for 40s. Rough numbers for oem scrub radius.

so with the portals the penalty on scrub radius is 3-4 inches or 75-100 mm. For a 37/38 you will need a +90 or greater wheel offset. Never going to happen. so best to just maximize positive offset that you can fit without interference.
 

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King pin axis is about 20 degrees from vertical. So roughly 10-15 mm of offset for every inch of height gain. So 30 mm offset for 35s, 15-20 mm for 37-38, and 0 mm for 40s. Rough numbers for oem scrub radius.

so with the portals the penalty on scrub radius is 3-4 inches or 75-100 mm. For a 37/38 you will need a +90 or greater wheel offset. Never going to happen. so best to just maximize positive offset that you can fit without interference.
Portals add width but also drop so the scrub penalty isn't 1:1 with width gain
 

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Yes indeed. Not sure how much they drop. Would be interesting to get exact numbers for 74weld design. A 1:1 drop wrt width gain (4” drop and 4” of width) stilt results in big increases for scrub radius. Center of contact patch is pushed out 45 deg but kingpin pavement intersection point is only moving out at 20 degrees.

You will get back some offset from drop in portals but at diminishing returns. Still best to maximize positive offset if wanting to minimize scrub radius. Don’t think you will be able to get a wheel that gets you all the way back to oem scrub radius.
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