First flex test! Pop!

[jross20]

So guys, I tested my flex for the first time today. She had way more flex that I thought was possible with 906's. So cool. I can tell that I need to extend the sway bar links... Haha.

But, what started me was a pop sound that only seems to happen as the suspension returns to normal. I say pop, but it sounded like a quick "DUNdun". She drives normal after the flexing and no amount of wiggling (turning left and right at 20-30mph) causes the noise. I went over our churches MEGA HARSH speedbump, (less than 2-3 mph of course) and again no sound.

So...is this sound the springs? Or the swaybar complaining? I don't see any damage or strange issues. But I don't want to ignore something that needs to be addressed.

(Also, does anyone's abs freak out during slow flexing? It made me gently roll back down the small hill o was using lol)

 

[formulate]

Check that your rear sway bar bushings are where they're meant to be. While I don't know that the sound was the same, I had a similar experience: got pretty flexed on 906s in the rear, after which I had a metallic clang type sound when I was driving home. Turns out the bushing on the compressed side of the sway bar had popped out.

It was a simple fix. Just loosen the metal bracket and slide the bushing back into place. It hasn't happened since.

 

[Jlcabe]

I second the checking of your sway bar bushings. Same thing happened to me

 

[jross20]

Check that your rear sway bar bushings are where they're meant to be. While I don't know that the sound was the same, I had a similar experience: got pretty flexed on 906s in the rear, after which I had a metallic clang type sound when I was driving home. Turns out the bushing on the compressed side of the sway bar had popped out.

It was a simple fix. Just loosen the metal bracket and slide the bushing back into place. It hasn't happened since.

Okay I'll check that out. I'm not sure how it could pop out but I guess I'll see when I look at it haha.

I second the checking of your sway bar bushings. Same thing happened to me

I'll check and post photos.

 

[JWaldz]

[MENTION=388984]jross20[/MENTION]

Check your rear coil. 906's are a pretty standard duty mild lift coils good for ~2". When you are articulating the suspension your rear coil might be moving around due to being short. When you return back to normal the coil is sitting back in the upper perch and could be making that noise. Just go flex it out, go back there and see if your coil is about to fall out.

And yes, ABS is horrible on our 4Runners when lifted. Especially when you start adding larger tires & wheels, weight, etc..

 

[deves2]

the 906 springs are short when max flexing. I agree with Jwaldz.
Mine would "bang" back into place scrared me until I realized what it was.
I attached the black Cone thing to the frame so the spring could not go anywhere and that solved the problem.

 

[fishy3G]

the 906 springs are short when max flexing. I agree with Jwaldz.
Mine would "bang" back into place scrared me until I realized what it was.
I attached the black Cone thing to the frame so the spring could not go anywhere and that solved the problem.

How did you attach the cone to the frame?

 

[jross20]

How did you attach the cone to the frame?

Yes I'd like to know as well

 

[deves2]

there are 2 ways to attach the cones to the frame. I cut a small strip of 1" flat stock, drilled a hole in it, layed it on top of the frame above wher the cone is, (be carefull brake line on drivers side might get in the way..) and put a washer and bolt up through the cone. the hardest part and it wasnt really hard at all was getting my huge softball size hands up above the spring perch to put the nut on the bolt ....but its very doable. 30 mins done (ok took over an hour to come up with the idea....but I'm slow minded)

the second way is to drill hole in flange of black cone and drill and tap frame. I read about this idea long after I had done mine.

both ideas would work just fine. I never had any trouble with the cone coming loose or the spring popping again. drove it for thousands of miles ...no issues. then I went to a longer spring (more lift) and left the cones attached to frame.
hope this helps
Dave

 

[jross20]

there are 2 ways to attach the cones to the frame. I cut a small strip of 1" flat stock, drilled a hole in it, layed it on top of the frame above wher the cone is, (be carefull brake line on drivers side might get in the way..) and put a washer and bolt up through the cone. the hardest part and it wasnt really hard at all was getting my huge softball size hands up above the spring perch to put the nut on the bolt ....but its very doable. 30 mins done (ok took over an hour to come up with the idea....but I'm slow minded)

the second way is to drill hole in flange of black cone and drill and tap frame. I read about this idea long after I had done mine.

both ideas would work just fine. I never had any trouble with the cone coming loose or the spring popping again. drove it for thousands of miles ...no issues. then I went to a longer spring (more lift) and left the cones attached to frame.
hope this helps
Dave

Thanks for the detailed post man. If you don't mind, could you post some photos to show what you did? Pictures help my brain think :bravo:

 

[Brian.]

Thanks for the detailed post man. If you don't mind, could you post some photos to show what you did? Pictures help my brain think :bravo:

I hate to be snarky, but you can't visualize a bolt joining 2 things together? In one case it's just a bolt through some holes with a nut and washer on the other side, in the second the frame was tapped so the nut/washer isn't needed. Heck, you could probably use double-sided tape, or hot glue, to the same effect. Possibly even strong magnets.

 

[jross20]

I hate to be snarky, but you can't visualize a bolt joining 2 things together? In one case it's just a bolt through some holes with a nut and washer on the other side, in the second the frame was tapped so the nut/washer isn't needed. Heck, you could probably use double-sided tape, or hot glue, to the same effect. Possibly even strong magnets.

It's not so much the bolts but the location, I was trying to look up photos of the cones and frame above them to get a better idea.

 

[BostonJon]

Sounds to me like perhaps the saw bar is binding within the bushing and then popping lose under pressure when your suspension evens out. As someone else mentioned, you can loosen the metal brackets, lube the bushings, and tighten them up again. There is a torque value for them. Overtightened they will compress the bushing too much and not allow the sway bar to rotate properly within the bushing.

 

[fishy3G]

I hate to be snarky, but you can't visualize a bolt joining 2 things together? In one case it's just a bolt through some holes with a nut and washer on the other side, in the second the frame was tapped so the nut/washer isn't needed. Heck, you could probably use double-sided tape, or hot glue, to the same effect. Possibly even strong magnets.

I'm not really understanding where you are drilling the hole in the black cone either?

 

[Brian.]

I'm not really understanding where you are drilling the hole in the black cone either?

I've nothing vested here as I've not done this particular "mod" (and almost certainly never will, my 4wd will probably never see much more than fire roads and snow/ice). But no one is drilling any holes in the bump stop (cone) as there's Already a hole. They are drilling holes in the FRAME so they can run a fastener through the bump stop and secure it to the frame. That turns the bump stop into a spring guide, which keeps the spring from flopping off-position when at full flex.

Essentially, with that bump stop held to the frame instead of being nestled inside the spring, anytime the spring comes loose during extreme maneuvers, it is guided back into perfect position by the bump stop.

Having now actually looked at one (Timmy's video on replacing springs/shocks), I see that glue/magnets/tape/etc wouldn't work without further modification as the base is hollow. Similarly, I wonder if that space is compressed at times and the viability of threading the frame vs having a through-bolt that could "float" a little more readily. But I'm just theorizing....