Rear end clunk hitting bumps and potholes OME suspension

Ok, I’ve done a lot of changing things around on my truck lately. I recently installed an OME suspension kit all the way around, with two AAL in the rear. Before that I was running an airbag helper spring setup to level the truck. The suspension is much stiffer than with the airbags.

The noise that I’m hearing sounds like the receiver hitch bouncing up and slamming back down to create the noise. Unfortunately, my noise isn’t that simple because I removed it without any change. I’ve removed nearly everything that I have installed aftermarket, except for anything with the suspension, no change in the noise.

Tomorrow, I plan on setting a camera up in a few places, because I can’t recreate the noise with the vehicle stopped. I’m going to try to find out if it’s something in the bed, or with the suspension.

My main question is basically the obvious question. Is this noise normal, or to be expected? A couple of things to take into consideration is that I stiffened the frame with weld on reinforcements, installed bed corner braces to stiffen the bed sides, and welded on rock sliders. That takes a lot of the flex out of the situation (which could be my problem.)

As far as I can tell the bed bolts straight to the chassis, without insulators/bushings. With all of that said, and taking that into consideration, I went and put stiff springs with urethane bushings on there. Does this sound like a normal noise, to be expected with all of the upgrades? I’m thinking no, but it is possible that hitting a bump rattles everything on/in the bed, even though it takes multiple holes to get the truck to make the
clunk/pop sound over and over. If I hit one hole, the noise happens once, it’s a harsh noise.

I have checked and rechecked everything that I could think of, and if I tapped on anything that makes a noise under the truck, I insulated it, so it no longer makes noise. Still haven’t found my original noise though.

I don’t have any friends with a first get to compare it to. I’d like some type of feedback, after I get some video footage, I will post it here for understanding the noise that I’m dealing with. If there’s anywhere to ask this question, I figured it would be Tacomaworld.
Thanks in advance!

 

sounds like you've been through it pretty thorough, its a 3.4 auto correct?

 

Yes it is a 3.4 auto. Thorough isn’t a strong enough word. I’ve been hunting this for a solid 14 days total, off and on whenever I feel like searching for it. I pulled the skid plate off of the gas tank and put rubber in between the gas tank and the skid plate because it was rattling when I tapped it with my fist. It’s driving me crazy. I may purchase some chassis ears from eBay, the old corded style is only $100.00, if I can’t tell anything with the camera tomorrow.

 

Check and make sure the ubolts are torqued to spec (90 ftlbs). I had 2 loosen up slightly and I was hearing a clunk coming from the rear. Torqued em back to spec and no more clunk.

Good idea to check torque on any suspension components after install and road time.

Also check the guides... don't want them too tight or too loose. That metal sleeve, you want it to be able to move a bit. Not tightened up to the point it doesn't move.

 

Curious to see those videos. Could be your drivetrain causing issues. Slip yoke smack!
I’m going through everything suspension wise myself and I have to remember to lube the drive train.

 

I’ll check the torque of the u-bolts again. I re-torqued everything after the first 500 miles. Nothing was loose then, but could possibly be now. I have looked at them really close, and don’t see any signs of movement (shiny spots, rust streaks or anything like that). I’ll also check the spring eyes and shackle bolts. I did have trouble with my front left spring eye bushing. It actually broke the OME urethane bushing at one point. The best I could tell was in the past the first time I removed the spring bolts, that bolt had to be cut off and the surface of the inside of the flange that squeezes the bushing together is really rough due to my saw blade marks. I had originally ordered Toyota spring eye bushings because that’s what it said I needed in the arb book, then the springs showed up with urethane bushings. Instead of going back with urethane bushings on the eye of the springs, I just used the Toyota OEM bushings that I had already purchased and had them here already. I replaced both of the spring eye bushings with factory bushings, and I oriented them and torqued them like the service manual states, with the truck on the ground at regular ride height.

 

Well guys, no luck with the camera today. I've got a lot of footage, from both sides and the driveshaft. Nothing seems out of whack, everything seems to move smoothly, and on top of that you can't even hear the clunk. I don't have a go pro or anything like that. I had to fill up with gasoline this morning, the truck really doesn't make as much noise with a full tank of gas....32 gallons total, not including the jerry can. I'll have to wait until this tank gets close to empty to see what's going on. My camera was mounted upside down at times and it's really not even worth the trouble of uploading any footage at this point, as the noise can't be heard. I could hear it in the cab, but not on the camera footage. After today, I'm really starting to consider my sanity as an issue. LOL! I have a weather guard pack rat pull out toolbox in the bed. I have always assumed this is where the noise was coming from, as I can smack it with my fist, and it sounds like I'm ringing a bell. I have removed the drawer and driven the truck, with no change in noise, but I have not removed the entire toolbox. It still sounds the same when the drawer is removed, driving or tapping it. I did place the camera in the bed of the truck, and it did seem to vibrate pretty good, but that was just with it on a tripod, still no distinct clunk like I hear in the cab. Maybe I should take a video of the inside of the cab and see if the noise shows up there.

I've also been giving thought to sound deadening my cab. Not only for noises, but road noises. I have a hands free Bluetooth that's basically useless at highway speeds. I have to yell; I'd rather hold the damn phone to my ear. Can anyone verify that sound deadening the cab is worth the hassle?

 

Is your exhaust able to hit the springs or anything else

 

No, unfortunately it’s not going to be that easy. Although I have “overthought” problems, and it turned out to be something very simple. Just happened this past week at work, actually. I am an equipment technician for a living. I have a pretty nice shop with a lift. All of the work done to my truck, I’ve done myself. With the exception of alignments and such. Most of the time noises stand out like a sore thumb with a vehicle on the lift. This one is tricky..mainly my fault because I’ve put so much shit on this truck. It happens over bumps and stuff. If I ride slow with my right side tires off the road, the noise goes nuts. It’s more of a rattle sound then, when it’s bump after bump. Yesterday I even got a video of the front sway bar because the noise sounds like sway bar links…only coming from the rear. Unfortunately, the video isn’t much help because nothing is obviously hitting together. I’m thinking seriously about the chassis ears, I have experience with those finding noises.

A good example of another noise that can’t be seen in a video, because it can’t be seen standing in front of the engine making the noise, is an idler pulley on a serpentine belt set up. You can see clearly all of the different components turning, but the easiest way to find out which one is making the noise is with a stethoscope. When you touch the component making the noise it will scream at you. Sometimes it radiates from the component, so you go with the loudest one. Could be an idler, tensioner, water pump, alternator, ext. Of course once it gets bad enough it will show itself.

Another way that I actually used my lift to try and find the noise, is outside of the box, but turned up negative as well. The noise happens over bumps and the truck is shaking up and down. I thought about it and I started to lower the truck on the lift and then started bumping the hydraulic lever, effectively shaking the truck up and down because the lift was starting and stopping. My point to this crazy test is that if it were my rear bumper, or any of the other 99 things that I have mounted on my truck, it should make the noise then. The truck was silent, but I can’t hit the hydraulic lever at a frequency to mimic driving over many bumps one after another. It’s a two post lift, so the suspension is dangling. I’d love to give that test a try using a drive on lift, that way the suspension would be shaking as well.

 

Throw up some pictures of the suspension. Let's have a look.

 

Here ya go! Excuse them being so greasy, I’m at the point that I’ll try just about anything. The guides I extended, because they were actually rubbing on the top spring, because of the number of springs in the pack. Btw, three of the four u-bolts moved when I re-torqued them yesterday, not a flat but just did move. I also tried to get some of the other components in the photos, air tank, aux fuel tank, and transfer pumps that could possibly be making a noise. I’m not at my shop right now, so these will have to do.

 

You definitely have a lot going on underside!

Looks like you're missing something. A little concerned about your ubolts there, might consider longer ones so you can grab more thread. Just a thought. Will continue to look, just two things which jump out on initial glance.

 

I was sold these u-bolts because they were supposed to fit, wheelers off road sold them to me, the nut is a very deep one if that makes any difference. These are actually the EL springs. It’s an even longer story, but anyway the guide you pointed out was how all of them used to be. I welded extensions on the other 4, those in the middle were tall enough. The guide itself is threaded, and they are to the end of the threads on the bolt (how they came from OME)

 

Yeah, I haven't personally seen the EL pack up close. Still, I would think there should be a damn nut on that thing. Oh well. Did you install with an AAL (or more)?

There are the 53B ubolts which are a little longer and would be required with an AAL. Granted I'm running the CS046R pack so it might be different from the new pack but with a single AAL I had to switch to the U53B ubolts.

(src: https://www.headstrongoffroad.com/store/p107/OME_U-bolts_-_OMEU53A/OMEU53B.html)

 

Thanks, I’ll take that into consideration for purchasing. Like I said before, it’s a long story. Short version, I ordered everything individually, not the kit from 4wparts. Took over 6 months for them to ship, was in 2020. I received one leaf pack of the old part number. The other leaf pack was lost by ups. Arb made it right, and actually sent me a complete set of the EL springs, and told me to destroy the old part number spring that ups did deliver. When I installed the springs, the truck still sagged in the ass end, because of all the weight back there. Supposedly the AAL was the entire hold up on my kit. Instead of ordering another set, I actually disassembled the old part number leaf pack and through the process of trial and error, finally got the ride height where I wanted it, by adding leafs from the old part number springs. The EL springs come with a spacer in between every leaf. Removing those spacers will add around an inch of lift, and you could use the factory u-bolts again (new ones). The reason it adds lift is because it exerts more pressure on the spring. I have 10 leafs on each side….. and finally got it level and up and running. It was a total pain in the ass! I didn’t want to wait another 6 months for another AAL.

 

Total pain in the ass, sounds like it! I wont even ask about your center-pin solution

 

There was no trouble at all with the center pin, it was more than long enough, after removing the spacers between each leaf. The EL springs don’t contact each other except for the center pin, they are separated by spacers, and at the end of the spring they have the plastic bushing. I dug up a photo of the spring when I got it, you’ll have to zoom in on the new spring to see the spacers that I’m talking about.

 

Those u-bolts are giving me anxiety man, look way too short....if they loosened up at all that rear axle might peace out on you one day.

Should have at least 4 or 5 threads coming out the bottom, the OME u-bolts that are recommended with their lift springs usually have about that much showing post-install.

I know some people trim theirs so they're flush with the nuts, but yours are still recessed into the nuts a bit which is scary.

 

I originally thought the same thing, and I may order some longer ones. The point that made me keep them is that they are fine thread, and the nuts are 3/4” tall. The stock nuts are 1/2” tall. If I had used the stock nuts, a few threads would be exposed like you guys say.

 

As long as thread engagement is roughly the diameter of the bolt or longer, there’s not really a strength issue, even if it looks scary