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IFS vs. SAS (don't throw rocks until you read)

Stuckinthe80s

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Ohhh buddy. That thar is a can of worms.

There really isn’t a right or wrong answer here, but I’ve been down a few of these roads. As was said above, it’s really about what you want to do.

Long Travel isn’t worth it, to me, unless you are going to hit the big air in the desert or the dunes. And even there, to actually do that without destroying the truck, you are going to be pushing over 10k.

if you want cheap reliability on difficult trails and are okay with tinkering until you get it right, you can’t beat a solid axle swap on an old truck. And if you want to wheel with the big boys, you need it. Sure U4 cars can run the big rocks with IFS, but one U4 CV is more than your typical solid axle swap.

ifs will go anywhere you want to go and still keep the body straight. And even go some places that’ll twist the body. My third gen did just fine up in the Black Hills, Over in BFE, up Blanca, And Holy cross. It’s got some crumply bits in the same places solid axle rigs took crumply bits on those same days. In fact I can only think of one time I’ve had to pull cable and that was in a mud hole. In a lot of cases, I have had zero trouble while solid axle rigs struggled behind me. So I don’t agree that a solid axle is better for rougher terrain, up to a point.

that said, IFS is going to have problems in the rocks, eventually. You will battle alignments constantly, and by extension, you will ruin a lot of tires. It is very difficult to find alignment shops that can properly align lifted IFS. And you have to learn how to drive it, or you will blow axles and diffs all day. To wheel hard, a front locker is mandatory, which is a significant investment if you plan to solid axle swap anyway.

someday I will solid axle a truck. I have a few axles sitting in my yard. I just can’t decide how to, and never seem to find the time these days.
One other thing to consider DDing a LT truck. Unless you invest in some glass fenders, you will throw rocks into your mirrors and windows and paint. A lot. And coat the windows in slime during every Snow storm. May not bug you but something to keep in mind.
Thanks Isaac! I was hoping you would chime in. I really liked how you were going with Baby Beast and I appreciate your input.
 

DaveInDenver

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I completely agree with Isaac about a front locker. Can't say you will *never* break an axle but a front locker and low gears are the key, which is not to have to constantly stab the gas pedal.

RPM and spinning wheels that suddenly get purchase is what kills CV joints. The locker keeps both wheels spinning at the same speed and with IFS you will lift wheels. With an open front diff the lifted and unladen wheel can start spinning fast.

With ball joint spacers and N98 OME shocks you can bind the CV axles on torsion bar IFS. I didn't even bother running ultra low profile bump stops. You can get respectable travel. Imelda's right side wheel isn't even fully stuffed here.

rubithon_23_mid_articulation_lines.jpg






But don't take poor lines and for the love of God pay attention to your spotter!

rubithon_34_mid.jpg
 
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Squishy!

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I think all folks before me pretty much nailed it. I'll just add that I wheeled the ever-living HELL out of my IFS pickup with just a rear locker on 33's and 35's. For me switching to solid axle was about the reliability and stability a solid axle provides. That's pretty much it.

Travis had a terrible bracket lift on his that definitely skews his opinion, but he's not afraid to bomb down a dirt road at a million miles per hour with his 3-link.

Also go check out Blazeland Longtravel for a cool budget friendly LT option.
 

Inukshuk

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Next up: Mud Terrain or All Terrain, followed by regular or synthetic oil? ;) Just having some fun.
 

AxleIke

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T
Thanks Isaac! I was hoping you would chime in. I really liked how you were going with Baby Beast and I appreciate your input.

The original Baby Beast was a great truck and I miss that thing. There are a number of things I would do differently though.

the flat belly was awesome off-road but made the on road miserable. It was so hot and loud that it’s hard to justify it. And why I never went that route on Baby Beast II.

I also did not like the funky 3 link. I’m not a fan of leaf springs but an IFS truck should have a 4 link. Three links work well in a dual 3 link system or in the front only. The geometry is hard to do well in the rear only.

even with all the mods on the original baby beast, my third gen is way more capable than the first gen. For IFS, the recipe is to stay at or below 33s, lock front and rear, and add lots of gearing.

I’ll add that lots of people think I don’t like solid axles or swapping trucks. That isn’t true. What I don’t like is the internet telling complete newbs that they need to solid axle a truck that they will NEVER use in a situation that comes close to needing a solid axle.

If you like the technical terrain and big rocks, you will want a solid axle. Like i said, you can’t beat the reliability for the cost. But as everyone else points out, if you just want to throw the camp gear in and hit the highway and some dirt roads to a choice spot, leave it IFS (for modern trucks).

All of that said, when we are talking about the early IFS that was on baby beast (86-95), a Conestoga wagon with square wheels rode better than that abortion of a suspension design. I’m not sure where Toyota got it in their heads that torsion bars were a good idea but they aren’t. Either cut it off and hang an axle or go coil over when you go long travel. I wasted a lot of time and energy on that crap. (I’m not bitter or anything...)
 

DaveInDenver

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Since Toyota was making solid axle and IFS Hilux side-by-side I think Hi-Trac IFS was about reliability, part commonality and just fitting. Getting the coil-over, CV axle and steering as well as engine and front diff locations to all play nice takes some 3D engineering and when they dedicated to IFS in 1996-1997 time frame they could dedicate the frame and sub-component design to make it work well. And even then there's the lower ball joint in tension issue.

I figure Toyota knew torsion IFS was transitional and that's why it took 10 years to get the 1st gen Tacoma/3rd gen 4Runner design done. Gotta remember it was 1986 when that happened so a lot of the work was still done with pencil and paper and mocking up models. The software and tools a guy in his garage has to design links and fabricate are better than what an OEM had back then.
 
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Stuckinthe80s

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The original Baby Beast was a great truck and I miss that thing. There are a number of things I would do differently though.

the flat belly was awesome off-road but made the on road miserable. It was so hot and loud that it’s hard to justify it. And why I never went that route on Baby Beast II.

I also did not like the funky 3 link. I’m not a fan of leaf springs but an IFS truck should have a 4 link. Three links work well in a dual 3 link system or in the front only. The geometry is hard to do well in the rear only.

even with all the mods on the original baby beast, my third gen is way more capable than the first gen. For IFS, the recipe is to stay at or below 33s, lock front and rear, and add lots of gearing.

I’ll add that lots of people think I don’t like solid axles or swapping trucks. That isn’t true. What I don’t like is the internet telling complete newbs that they need to solid axle a truck that they will NEVER use in a situation that comes close to needing a solid axle.

If you like the technical terrain and big rocks, you will want a solid axle. Like i said, you can’t beat the reliability for the cost. But as everyone else points out, if you just want to throw the camp gear in and hit the highway and some dirt roads to a choice spot, leave it IFS (for modern trucks).

All of that said, when we are talking about the early IFS that was on baby beast (86-95), a Conestoga wagon with square wheels rode better than that abortion of a suspension design. I’m not sure where Toyota got it in their heads that torsion bars were a good idea but they aren’t. Either cut it off and hang an axle or go coil over when you go long travel. I wasted a lot of time and energy on that crap. (I’m not bitter or anything...)

Isaac, were you still running factory torsion bars? I can't remember seeing it in your build thread but I'll probably look again after posting this. The reason I ask is because I've always found the torsion bar setup on my Hundy to be exceptional. It is one of the best road trip vehicles I've ever owned. That being said, it certainly does not absorb the bumps off road as well as I would think but I know that is more the product of running stock shocks that were designed for street use comfort rather than offroad absorption.

Right now my 4runner does indeed ride like a square-wheeled wagon but I suspect it being because the torsion bars might be cranked and rear shocks being completely shot. I'm hoping that new OME torsion bars and nice shocks will help up front and maybe some chevy 63" springs/nice shocks will help in the rear. My feeling is that the spring rate and memory on the metal used on the factory torsion bars wasn't great to begin with and just became completely useless over the course of 30 years of use.

And one last note for what it is worth, I've never thought you don't like SAS, I've always been under the impression that you were in the pursuit to show that it wasn't absolutely necessary. It's good to learn from others though and I'm glad you've already field tested a lot of the things I've thought about during my daydreaming sessions on the matter. :thumb:
 

Stuckinthe80s

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Your signature says it all...

I giggle every time I read that quote, lol.

I completely agree with Isaac about a front locker. Can't say you will *never* break an axle but a front locker and low gears are the key, which is not to have to constantly stab the gas pedal.

RPM and spinning wheels that suddenly get purchase is what kills CV joints. The locker keeps both wheels spinning at the same speed and with IFS you will lift wheels. With an open front diff the lifted and unladen wheel can start spinning fast.

With ball joint spacers and N98 OME shocks you can bind the CV axles on torsion bar IFS. I didn't even bother running ultra low profile bump stops. You can get respectable travel. Imelda's right side wheel isn't even fully stuffed here.

View attachment 88064





But don't take poor lines and for the love of God pay attention to your spotter!

View attachment 88065

And for stuff like this, I'd definitely be taking the 80. That is, if I can quit messing with it and just drive it, lol. The 4runner won't be seeing any action like this. Well, maybe. :shots:
 

DaveInDenver

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And for stuff like this, I'd definitely be taking the 80. That is, if I can quit messing with it and just drive it, lol. The 4runner won't be seeing any action like this. Well, maybe. :shots:
Never say never!

Are you planning bumper, sliders, double case or/and skid plates? Stock bars with 1.5" ball joint spacers rides pretty cushy compared to 25mm OME/Sway-A-Way if you don't need the spring rate to hold up a lot of extra weight.
 

Squishy!

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Never say never!

Are you planning bumper, sliders, double case or/and skid plates? Stock bars with 1.5" ball joint spacers rides pretty cushy compared to 25mm OME/Sway-A-Way if you don't need the spring rate to hold up a lot of extra weight.

I agree with Dave. Ball joint spacers are cheap and plenty reliable. I'd also go Total Chaos Idler arm and refresh all the steering components. My last IFS truck would get serious issues with the front tires trying to go different directions when in 4WD. I had far fewer driveability issues when I replaced all the joints and Idler arm
 

DaveInDenver

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Total Chaos idler is the bee's knees. Imelda has one and it was the last idler I put on, which was probably 15 years ago. AFAIK it's still fine and it held alignments as well as can be expected.

But I will caveat saying that when I did the idler the price wasn't hard to take. It's now a $500+ upgrade. For Spanky's 4Runner here on a budget I'd probably recommend just rebuild a stock arm with Roger Brown's bronze bushings.

http://www.4crawler.com/4x4/ForSale/IdlerArm.shtml

And regarding alignments, don't forget to brace those rear lower arm mounts. I don't know who still makes them, I used Sonoron Steel, but even just fabricating something yourself is pretty important to keeping the front end square.

final_fit.jpg
 
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Stuckinthe80s

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I agree with Dave. Ball joint spacers are cheap and plenty reliable. I'd also go Total Chaos Idler arm and refresh all the steering components. My last IFS truck would get serious issues with the front tires trying to go different directions when in 4WD. I had far fewer driveability issues when I replaced all the joints and Idler arm
I'll look into the TC idler. As far as the other stuff, the Beck Arnley branded steering components on Rock Auto is supposed to be 555 stuff so that is the route I'm going with that. I'm loving the service costs associated with the mini trucks! So far that is.

Total Chaos idler is the bee's knees. Imelda has one and it was the last idler I put on, which was probably 15 years ago. AFAIK it's still fine and it held alignments as well as can be expected.

But I will caveat saying that when I did the idler the price wasn't hard to take. It's now a $500+ upgrade. For Spanky's 4Runner here on a budget I'd probably recommend just rebuild a stock arm with Roger Brown's bronze bushings.

http://www.4crawler.com/4x4/ForSale/IdlerArm.shtml

And regarding alignments, don't forget to brace those rear lower arm mounts. I don't know who still makes them, I used Sonoron Steel, but even just fabricating something yourself is pretty important to keeping the front end square.

View attachment 88144
Yes, the rear lower arm brace is on the list. I'll probably just fab it up. Anyone know where I can get measurements to make sure it isn't already tweaked? I'm assuming it isn't as the PO had the truck for 23 years and the only offroading he did was a FL beach. There aren't a lot of dunes to jump on the east coast.
 

Stuckinthe80s

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Never say never!

Are you planning bumper, sliders, double case or/and skid plates? Stock bars with 1.5" ball joint spacers rides pretty cushy compared to 25mm OME/Sway-A-Way if you don't need the spring rate to hold up a lot of extra weight.

You're right. At some point I'm probably going to come to my senses and quit trying to spread my money across 4 projects. That will mean I'll probably sell the 80, finish building out the 100 and use the 4runner as my solo exploration vehicle when the family isn't with me. That will allow some $$$ to go towards the C10 so it can quit being a yard ornament.

If I go that route, then yes I will put a bumper, sliders and skid plates but no plans for double cases. I'll probably put a winch on there also before lockers so I think the OME's will be merited.
 

DaveInDenver

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Yes, the rear lower arm brace is on the list. I'll probably just fab it up. Anyone know where I can get measurements to make sure it isn't already tweaked? I'm assuming it isn't as the PO had the truck for 23 years and the only offroading he did was a FL beach. There aren't a lot of dunes to jump on the east coast.
AFAIK there's no spec for it in the frame dimensions but IIRC supposed to be around 16.75" or so between them. I think it should be the same as the forward mounts to perhaps use that as a reference.
 

AxleIke

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I still have the old brace from Baby Beast. It was the prototype Sonoran Steel one. Just sitting in my steel storage. Yours for a 6 pack.
 

HoneyBadger

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I’ll submit this picture for my main argument FOR a SAS. Good luck doing that in an IFS truck without breaking something.
48728321-DDC5-4BE8-AFF6-9717C857C5D8.jpeg


I consider the front 3-link on a SAS to be the “long travel” of the SAS world. I can fly down most trails with ease. I think that’s the main thing people miss when doing a SAS. They try to do it “budget” and end up with some crappy TrailGear front leaf springs that make the trail ride feel like re-entry to the earth’s atmosphere in a VW Bug. That being said I spent an ENORMOUS amount of money on my SAS with the Diamond axle and the stage three 3-link kit. But I’d say it was comparably priced to a proper full LT system. Once it was properly tuned, it eats trails for breakfast and cruises the highway like a Cadillac. I can do 75+ down the highway just fine after having blown through a trail at 25-35. (I once did Mosquito in less than 45 minutes.)
-
I’ve seen plenty of well built IFS trucks do just fine over a lot of crappy stuff. And I’ve also seen a lot of CV axles explode like frag grenades.
What @Squishy! said about my old IFS system was true. I had a HORRIBLE drop bracket lift, stock control arms, and worn out bushings. That system was absolutely obnoxious. It was literally impossible to align it and it burned up tires. It would blow CV axles just sitting there while you looked at it. So it really made me loath IFS, especially when I saw SAS trucks doing things with ease that were literally killing my truck. For me, I had no choice but to go to a SAS. Some of the frame was already removed for the drop bracket. So bigger and better was my only option.

I totally agree that for most folks, who want a reliable adventure rig to take the kids out to some cool places, a well modified IFS is a good solid choice. There’s nothing wrong with that.
But if you want to be able to roll out and drive to the trail head, wheel Holy Cross, then drive to Leadville for dinner, then wake up and Baja over Haggerman to Basalt the next morning, then cruise back over Independence and all the way back to Denver... The 3-link SAS is where it’s at. Very capable all around. Way over built for most stuff but perfect for those special trails that demand the next level gear. Also, not a trailer queen. I think it’s a win-win-win.
3C5E119D-DD3E-48A2-B7B2-96ABA8C35AC7.jpeg

On this most recent Ghost Town Run, we didn’t really do anything where I needed my truck’s full crawler potential. But it was pleasant to drive on the long highway sections, the dirt roads, and the bumpy trails. I really like feeling WAY overbuilt for most things. Then when I really need it, I know it’s there.
That being said, it’s definitely not for everyone and I can respect that.
My story is one of “cheaping out” trying to have a “cool lifted truck“ only to find that I had made a huge mistake that forced me to spend the money to do it right in the end. So the moral of that story is, keep it mild or spend the money and do it wild. But if you do it big, do it right.
 
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Stuckinthe80s

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I still have the old brace from Baby Beast. It was the prototype Sonoran Steel one. Just sitting in my steel storage. Yours for a 6 pack.
Thank you sir!
 
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