Sniv's Custom Long Travel Build

[snivilous]

Link Failure Explanation

[MENTION=91297]Kraze[/MENTION] Do you have a rear sway bar or run it disconnected ever?

Because the links are all pinned-pinned, they are a two force member meaning they should act in compression and tension only and my link didn't get pulled apart from tension or buckle from compression. I started thinking, and the only way it happened (which is confirmed by the breaks conical shape) is from being twisted which is a result of the 4-link binding. I think I broke the link from having extended shocks (Tundra 5100s) and no sway bars, so I overflexed and the links started to bind and that one failed.

 

[snivilous]

So after I pulled my shocks Friday, I go to reinstall them and get a call from a Jeep buddy that he's having fuel issues on a trail. So I drive out to help him, missing a rear upper link, no rear shocks, no sway bars--talk about a scary ride! We eventually called another guy who came and towed him home since we couldn't fix the fuel issue without dropping his bash plate.

So yesterday I installed the rear shocks again, then my buddy fixed my CB microphone cord that had the connections come apart, then I drove to another buddy's place and he welded my link back together

So of course, testing was in order in the form of a 3-hour offroading adventure at 9pm.

One of the guys who came along just had to be in every photo

There was at least a good 8" of snow where we explored.

And this is the edge of the lake you can see not covered by snow.

And an inside panorama, the camera doesn't pick up all the light very much so the spot beams aren't quite as distinctive and create a more consistent glow around the whole truck.

 

[Kraze]

[MENTION=91297]Kraze[/MENTION] Do you have a rear sway bar or run it disconnected ever?

Because the links are all pinned-pinned, they are a two force member meaning they should act in compression and tension only and my link didn't get pulled apart from tension or buckle from compression. I started thinking, and the only way it happened (which is confirmed by the breaks conical shape) is from being twisted which is a result of the 4-link binding. I think I broke the link from having extended shocks (Tundra 5100s) and no sway bars, so I overflexed and the links started to bind and that one failed.

When I broke that one, the rear sway bar was hooked up. I too have extended shocks, and had extended links on the sway bar (had a set for the front that I put on the rear).

Nowadays, I'm running no sway bars, so I'm guessing I shouldn't be shocked if I break another stock one. Thanks for the detailed explanation though! At least now when I break the next one, I will know why haha.

 

[eddiebx]

4 months and 8 pages later, still no sign of long travel anything being built, aside from some microsoft paint renderings :hiding:

:jk: so jealous of you people who have access to all that metal fabrication equipment, can't wait to see this finally pan out!

 

[Fishwerks]

You have a lot of friends who break stuff…glad to see you out using the truck a lot though!

 

[snivilous]

I found out I'll be going home for thanksgiving, I'm hoping there's nothing important going on Monday/Tuesday in class so I can skip them and get a full 9 days off. Regardless, I'm going to try to order some parts/metal so I can build a prototype for one side and take the IFS apart to get exact dimensions that I can't get at school.

I also need to obviously beef up my rear links, so I got thinking about adding uniball/ball joint/heim/wtf to the ends to relieve the stress when the rear axle moves. The bushings that come stock aren't meant to rotate on any axis besides the way they are bolted, though this wouldn't let the axle rotate from side to side (so it'd be restricted to up and down, which technically the panhard/track bar forces it to move in an arc and not strictly up and down). This means the rear bushings are forced to contort for the axle to move.

The moment on the links (causing them to twist and what caused mine to fail) from the bushings fighting the movement of the axle can be somewhat alleviated with a single joint on one side. With two joints and enough room for the joints to have full movement, I don't think the axle would bind at all through its full motion range, though SolidWorks was having trouble with the model so I couldn't get the axle to "flex" half the time... I talked to one of my buddies, and he said that you want bushings on one side to dampen the motion of the axle to the frame, which stuff I've read also said that and it makes sense. So all this comes down to the fact I will have a bushing on one side of my new links and a uniball on the other side, with one side probably being adjustable for the hell of it.

Now for the more fun stuff, I have been working a lot on the lower wishbone design. An issue I've run into is knowing the loadings the arm is reacting. Obviously you have the wheel coming up (and the tire will flex drawing out the impulse), then you have the shock reacting it throughout it's full motion range but the shock doesn't bottom out, then you have the bump stop which is reacting over the last ~2" of motion to slow down the impulse force and the bump stop is exerting a force, and then at full bump the bump stop is taking the remainder of the full load...

So to solve that, I am reverse engineering other designs to see what stresses and forces they are designing too. Originally I was just going to assume the truck was dropped from 3-5 feet and total free fall since that seems possible if you're jumping but the loadings are insane... I am NOT copying other designs, I am just trying to figure out what stresses they are designed to handle.

This is with a 2000lb load where the ball joint would be, which seems easy to achieve since if you figure my springs have a rate of 620lb*in and if they compress 6" for the coilover that's over 3600lbs at full bump which means the tire is exerting at least 1800lbs of force assuming it's double the distance out on the arm.

With that in mind, I am seeing a peak stress on the shock mounts... which in this design are 3/8" thick steel with a 1/2" hole. Stock is like 1/8" thick with a 1/2" hole?! I don't get what I'm doing wrong if I'm almost exceeding the stress ability of steel with a 3/8" shock mount at what should be a realistic load on normal trail riding and the stock mount has 3x less area to react the load! So I need to figure out the loadings the truck will be seeing, since the arm can handle it, but the shock mount doesn't seem able to even though it's bigger than anything else (though again, I haven't compensated for bump stops taking load/slowing down the impulse or actually calculating the force the coilover puts out through the range of motion from full droop to full bump)... aww, mathematics. :faint2:

Thanks for reading!

 

[Broker]

Very interesting read. I hope building your own arms panout for you. I went the easy path and went with pre-fabbed arms. There was enough other stuff to figure out for me then to spend the time on the arms.
A few things I've learned from my LT experience with the runner is to keep a rear sway bar. I don't have one and this is by far the sketchiest thing, the body roll on mine when at speeds over whoops is a little bit puckering. Once I get my rear axle replaced I plan to run a replacement sway bar.
Also reinforce the frame, my frame is twisting from the loads I've put on the front suspension. My suggestion is to run a top shock brace to support the towers. I'm in the process of working mine out now. And reinforce the shock buckets if you keep stock mounting on the frame.
For the rear I have my own built links and it allows a lot of travel but not enough to keep up with the front.
I would highly suggest to avoid glassworks fenders. I have fiberworx tacoma fenders on my runner and they work but have some gaps.

 

[snivilous]

Very interesting read. I hope building your own arms panout for you. I went the easy path and went with pre-fabbed arms. There was enough other stuff to figure out for me then to spend the time on the arms.
A few things I've learned from my LT experience with the runner is to keep a rear sway bar. I don't have one and this is by far the sketchiest thing, the body roll on mine when at speeds over whoops is a little bit puckering. Once I get my rear axle replaced I plan to run a replacement sway bar.
Also reinforce the frame, my frame is twisting from the loads I've put on the front suspension. My suggestion is to run a top shock brace to support the towers. I'm in the process of working mine out now. And reinforce the shock buckets if you keep stock mounting on the frame.
For the rear I have my own built links and it allows a lot of travel but not enough to keep up with the front.
I would highly suggest to avoid glassworks fenders. I have fiberworx tacoma fenders on my runner and they work but have some gaps.

That's good to know, I'm definitely planning on reattaching the rear sway bar once I get my disconnect fixed but my reasoning had been for going around turns faster.

I'll also reinforce the frame like you said. Eventually I want to have shock hoops and run a beam over the engine to each one, but I don't know if I'll have time to fabricate that (though I don't think it should be TOO difficult, knock on wood).

I look at your thread and your Runner and Taco are sweet! How much travel do you have in the front and rear? It looks like my rear end with stock links is getting 11" of travel, though I will definitely go to new links soon.

And for the fenders, do you have some pictures? I couldn't find too much on your build thread. I didn't look around much, but the fiberwerx fenders didn't look very pretty from the pictures on their site (though they are a pretty ugly Taco I have to say). I read up on glassworks and how bad their customer service is, so I'll try to stay clear of them for sure.

 

[snivilous]

So I've been thinking a lot about the stresses my finite element model is seeing, and they were really worrying me. Though I realized about a half hour ago that the stresses should be fine! I am seeing a peak stress in my current design (which will get changed soon) of 37ksi at the shock mount with a 4000lbs tip load. I couldn't figure out for the life of me why the stresses are so close to yield when my shock mounts are WAY beefier than anything else I've ever seen and stock is only 1/8" plate.

Turns out my model wasn't modeling a bolt in like I thought it was, so I modeled the bolt in myself for the shock and then it started to play nice. I also figured out that my shock mount is roughly halfway out on the frame, meaning with a 4000lbs tip load the shock is reacting 8000lbs (I have yet to model in bumpstops). Though then I got thinking that my current coilovers only exert 3600lbs at full compression, and even with 10" travel shocks at 500lbs*in that's only 5000lbs of force at full compression, which means a tip load of only 2500lbs!

And you punch those numbers into the FEA, and voila! Peak stress of only 23ksi! So I would be surprised if I went over 30ksi peak stress at the shock mounts, even from running a very high spring rate and that would leave me plenty of room for factor of safety. And even if I hit yield stress it's just a small section of the shock mount, so everything should be fine still (in theory).

Tomorrow I will model in a lateral member under the shock mounts to distribute the load to the bottom of the arm instead of the current brace I have, and that lateral member will also be setup to transfer the loading of the bump stop which I will need to do calculations for next.

Summary: Shock mounts that are 3/8" thick are insanely strong and I shouldn't get near yield stress. And the arm overall is insanely beefy and hardly sees any stresses or deflections at current tip loadings (which by the way are probably higher tip loadings than my stock arms have ever seen).

Will post more figures and models when I can. I think since my design is so simply that I will hopefully be able to get at least one arm fully fabricated during thanksgiving break, maybe even get the full front long travel setup fabricated and working minus fancy shocks/hoops/frame stuff which would come around Christmas. Or just get the arms fully fabricated and bring them to school to help me continue model and analyzing the rest of the vehicle and where to go/reinforce. Thanks for reading!

 

[Fishwerks]

It looks like my rear end with stock links is getting 11" of travel, though I will definitely go to new links soon.

You're getting 11" of travel out of the rear right now?

 

[snivilous]

You're getting 11" of travel out of the rear right now?

I haven't fully let the axle droop by jacking up both sides, but when I was pulling the shocks last week I had 11" of flex from the axle to the bump stop. I would think full droop would be similar since there is less binding during normal droop than flexing.

 

[Broker]

I'm pulling about 13.5" in the front. I could pull more but my 35s don't really like to tuck with the LT. If I want to go further up I need to remove my inner fenders. And my drop is limited by the cvs binding up. In the rear I have not measure what I'm pulling. But I have 11" shocks and I use all of it. I can tuck the axle on the frame and it will drop for days if had longer shocks. The links I made for it don't bind any and will drop until the upper goes vertical.

Here is the gap the Tacoma fenders leave. I got burned by glassworks so i am completely against anything they do now.

 

[Illestreker]

Very interesting read. I hope building your own arms panout for you. I went the easy path and went with pre-fabbed arms. There was enough other stuff to figure out for me then to spend the time on the arms.
A few things I've learned from my LT experience with the runner is to keep a rear sway bar. I don't have one and this is by far the sketchiest thing, the body roll on mine when at speeds over whoops is a little bit puckering. Once I get my rear axle replaced I plan to run a replacement sway bar.
Also reinforce the frame, my frame is twisting from the loads I've put on the front suspension. My suggestion is to run a top shock brace to support the towers. I'm in the process of working mine out now. And reinforce the shock buckets if you keep stock mounting on the frame.
For the rear I have my own built links and it allows a lot of travel but not enough to keep up with the front.
I would highly suggest to avoid glassworks fenders. I have fiberworx tacoma fenders on my runner and they work but have some gaps.

when you built your own links for the rear did you change the length of them compared to stock? If so, this is what helps to gain some rear travel with the addition of the 11" shocks?

I want to build my own links eventually and would like to know how much longer to make them and if it will help gain extra rear travel.

 

[Broker]

when you built your own links for the rear did you change the length of them compared to stock? If so, this is what helps to gain some rear travel with the addition of the 11" shocks?

I want to build my own links eventually and would like to know how much longer to make them and if it will help gain extra rear travel.

I made them all stock length except the panhard bar. I didn't want to push the axle back with the stock drive shaft on and end up pulling the slip joint apart. the pan hard i just made it so the axle was centered at ride height, then adjusted from there to clear the shock hoops during wheel articulation. i don't remember what length it was.

 

[snivilous]

So I added the cross beam under the shock mount to distribute the load and also distribute the bump stops loading.

That alone lowered my peak stress to 22ksi from 29ksi! Again, I haven't modeled the bump stops in and their loading, this analysis is assuming the bump stop has yet to engage and the coilovers loading on the arm. I am very happy with it since the arms peak stress is around 50% of yield depending on the steel.

I am also getting 0.016" of deflection at the end of the arm with a 2500lb tip load which should be around the loading on the arm right before the bump stop starts engaging.

 

[snivilous]

Snow Wheeling/Camping

So a group of us went camping Saturday night and then wheeled a bit Sunday.

Our camp was across this lake tucked under this ridge.

There were 7 vehicles that showed up: Me with the Runner, two 97 Wranglers, a 98 Cherokee, a 95 Grand Cherokee, an old Chevy K50 or something, and an older F-250.

I just slept in the truck with a girl I brought, though some people brought tents. I didn't realize how much room the 4Runner has. I removed the rear seat cushions so there was room from the tail gate to the center console and that gave over 6'6" of room and then there is at least 3' of room between the wheel wells. Only hassle was I had to remove all my recovery/survival gear and move the subwoofer up front. It's a lot easier when it's just my German Shepherd so I don't have to move everything outside!

Today (Sunday), we went wheeling a bit after we woke up. We were in southern Idaho which we crossed into going up Franklin Basin, and then took a side trail to Gibson lakes where we camped at the second lake. There was at least a foot of powder in the shade and pretty slushy everywhere else.

Also, my stupid microphone on the my Uniden 520XL is such a POS. We thought we fixed it, though now it seems like it is BARELY receiving anything. Apparently the microphone is the transmitter and receiver, even though the receiver speaker is on the radio box. We plugged in my buddies microphone who has a Uniden, and it worked fine. Right now the speaker barely has any sound when someone talks (like you can't hear them if you are at anything over idle), though the meter shows I am transmitting and receiving... so we'll tear into the cord again and see what's up. So far I'm not impressed with Uniden.

Overall a fun trip! I forgot how much fun snow wheeling is, I think I prefer it over everything else and not just because the 4Runner seems to dominate at it Thanks for reading!

 

[Offroad_Medic]

Sleeping with attractive ladies in the back of the runner while on a camping/wheeling trip? So much win I applaud you good sir.

 

[turbo8]

Sent you a pm snivilous.

Also when you make your rear links, the frame attachment points should have bushings and axle attachments use heims.

 

[snivilous]

So I came home Thursday night, took 12.5 hours of straight driving to get through! Normally is 9 hours, but I hit three snow storms which delayed things a bit, but Red Bull kept me going!

The route I take cuts down on the eastern shore of Flaming Gorge, and then over into CO after crossing from WY back to UT then to CO. There is a long stretch of dirt road after you leave the highway and head towards the CO border, which actually was faster than pavement since it was grippier and I prefer dirt over pavement driving anyways :bounce: This picture was taken near 3-points, where CO, WY, and UT all come together.

Yesterday I just slept in and then hung out with my sister all day. Today I worked on the truck a bit. I had a date set for 4pm so I didn't have a lot of time, not to mention a guy is bringing his 3rd gen up tomorrow so I can help him install a lift so I didn't want to tear into the truck yet. So I went ahead and made a new sway bar disconnect pin, since I had the passenger side one (I only run the rear sway bar) fall off a few months back. It's pretty rare if I notice any body roll, I didn't think there was much to begin with when I lost the pin, so doing this is mainly because if the suspension flexes much the sway bar contacts my lower link and makes a popping sound. It's not an issue just kind of annoying, and I may as well be able to run my sway bar if I want to since it's on there...

So I just took a .75" bolt and cut it off so I had the smooth section, drilled the hole for the hitch pin (which wasn't perpendicular for some reason even though it was clamped and I used the drill press...) and then cut another .50" bolt and welded it on. The thread and smooth sections aren't on centerline, but it doesn't matter since the disconnects have spherical bearings on the ends.

I think it came out well enough. It cost about $5 versus $20 for the exact same thing for a Cherokee, and it gets the job done so who cares.

Awesome picture of it installed, you can see the top and bottom spherical bearings. You can also see I only have one bushing on the frame mount, I removed the lower bushing to try and move it up higher since the disconnect is like 4" longer than stock.

I also installed new lift gate struts:

I used these for $35: 2 96 02 4Runner Rear Door Hatch Liftgate Gate Tailgate Lift Supports Shock Arms | eBay

Honestly I am disappointed, they don't have enough force to raise the gate fully. They don't sag which is fine, and they fit with no issues (just needed some washers), though I was expecting to just open the hatch and have it swing open all the way. Granted my old struts sagged a little, but I still had to go and push the door all the way up as the new ones are too. Kind of a bummer but oh well...

And here is a picture of my sisters 1977 FJ40, almost done being totally rebuilt, I have to admit I'm jealous I don't get to drive it:

And for the hell of it, my German Shepherd:

I have a lot of stuff to do the truck, primarily to the bumpers which I'll start on after I help the guy with his lift. Should be a good bit of welding and fabricating going on in the next week. I'll also tear the IFS apart a bit to get exact dimensions for the LT, not sure if I'll make prototype arms just yet though...

 

[mrtucker80]

Great looking rig. I am especially interested in your 40" LED bar mounted up top. I really like the low profile look. I am now on a mission to see about getting something similar going myself. How is the light horizon that you mentioned. it looked from one of the pictures that you had pretty good coverage across the front of the rig.