Front End Bang

[4runnerWiniarski23]

Hi guys back here with another problem. My rig has been running pretty solid for a while, out of the blue I started to get a noise in the front end, front passenger side from what I can tell. I initially thought it was wheel bearing based on the rotational noise.

The best description I can give is as follows, noise happens when driving at any speed, sometimes louder at different speeds, noise is way worse once braking. It sounds like a bang or slap of something metal on metal, but its certainly something rotating, bang-bang-bang, faster or slower based on speed.

I had the truck on a lift and checked many many things, wheel bearings seem fine after checking for play or noise. I checked tie rods, control arms, ball joints upper and lower. Nothing seems to have so much play that it would cause such a loud noise. I checked CV joints, boots, everything with the axel seems fine. It will engage 4wd no issues, noise doesnt change 4wd or 2wd. I checked the driveshafts front and back, doesnt seem to have any more play than usual. I did swap out the sway bar bushing because they looked gone. I did a complete visual inspection of the frame found a few rough sports but not sure if maybe the frame is flexing? This wouldnt explain a rotation noise though.

Im scratching my head hard on this one, basically at the point where I have such an uneasy feeling driving the truck I might consider ditching it. I have a lot of time invested rebuilding many aspects hate to see it go, rear tires are basically new.

Any ideas on where to look or check just need a fresh set of eyes/mind. Appreciate everything as always, best forum around.

 

[Skulking]

I assume you have looked for witness marks? Did you check the back side of the wheels to see if something may be hitting one of them?

 

[TravThePro]

I just barely overcame a similar issue to this where 2WD and 4WD had identical noises coming from what sounded like a rotational banging from the front passenger side of the vehicle.

The first issue was a major play in the driver's side front diff clamshell needle bearing. I compared both of the 4Runners at my house (both have a front locker engaged, so it will likely be a little more severe than what you may get).
Here is what the significantly worn one sounded and looked like with only rotating the driveshaft Shared album - Travis - Google Photos
Here is what the second one that wasn't nearly as worn looked like Shared album - Travis - Google Photos

Replacing the needle bearing with the ECGS solid bushing made it completely solid. It also removed half of my clunking noise.

The thing that ended up completely solving the banging issue was taking the tires off and finding a hot spot (that burnt me) on the dust shield for the brake. I bent the shroud back with a few choice words and an embarrassingly simple issue was solved.

Edit: I just remembered an issue like this with one of the cars I bought salvaged to rebuild. The steel belt inside the tire separated and gave me a feeling worse than Jeep death wobble while I was driving it.

I chased the entire steering and suspension of the vehicle with no solution to it. If no other fixes end up working, try rotating your tires to see if that moves the problem to the rear of the vehicle.

 

[tx_shooter]

I had something very similar to this when my front clamshell gears were damaged. But I broke the gears wheeling the 4Runner pretty hard (stupid hard). If you cannot find anything else I would drain the diff fluid and look for small pieces of gear teeth. If the gears are going out it will show up in the fluid change. Don't worry though; a front axle swap can be done in 3-4 hours by one person.

 

[thennen]

I just barely overcame a similar issue to this where 2WD and 4WD had identical noises coming from what sounded like a rotational banging from the front passenger side of the vehicle.

The first issue was a major play in the driver's side front diff clamshell needle bearing. I compared both of the 4Runners at my house (both have a front locker engaged, so it will likely be a little more severe than what you may get).
Here is what the significantly worn one sounded and looked like with only rotating the driveshaft Shared album - Travis - Google Photos
Here is what the second one that wasn't nearly as worn looked like Shared album - Travis - Google Photos

Replacing the needle bearing with the ECGS solid bushing made it completely solid. It also removed half of my clunking noise.

The thing that ended up completely solving the banging issue was taking the tires off and finding a hot spot (that burnt me) on the dust shield for the brake. I bent the shroud back with a few choice words and an embarrassingly simple issue was solved.

Edit: I just remembered an issue like this with one of the cars I bought salvaged to rebuild. The steel belt inside the tire separated and gave me a feeling worse than Jeep death wobble while I was driving it.

I chased the entire steering and suspension of the vehicle with no solution to it. If no other fixes end up working, try rotating your tires to see if that moves the problem to the rear of the vehicle.

Echoing this, but my problem was on a Scion and no banging. I had a noise that sounded EXACTLY like a failing wheel bearing. Took it to a local shop, who put it on a lift and listened. They declared a failing bearing inside the transmission, no wheel bearing noise. Since this shop doesn't do transmissions, I took it to another local place. They diagnosed a bad tire, belt separation. I was skeptical, but had them replace the two front tires. Not a peep since.

It makes sense. in retrospect, as I drove to work every day, crossed a small bump almost two inches high across the entire roadway. It was almost like hitting one of those abrupt changes in elevation like in a construction zone, where the pavement had been taken down, and then you hit level roadway again. Pretty jarring to those small tires. I think that's what did it.

 

[Fiffa]

Been hunting the same thing and I read somewhere on here that it may be your brake pads - especially if you have the TBU (like me). When I first bought this 4R one of the retaining springs was broken, but I believe if you don't grease well enough or the grease that was originally on there wears out then you may not have the pads moving equally between the top (where the springs are) and bottom.

I need to get the truck on the lift to confirm, but it hasn't gotten worse in over 10k miles and I can see that the pads are going to need to be changed soon, which can contribute to a problem like that.

 

[TravThePro]

Been hunting the same thing and I read somewhere on here that it may be your brake pads - especially if you have the TBU (like me). When I first bought this 4R one of the retaining springs was broken, but I believe if you don't grease well enough or the grease that was originally on there wears out then you may not have the pads moving equally between the top (where the springs are) and bottom.

I need to get the truck on the lift to confirm, but it hasn't gotten worse in over 10k miles and I can see that the pads are going to need to be changed soon, which can contribute to a problem like that.

The banging noise should go away with the brakes being hit if this is the case. It would normally wear the pads diagonally if the grease wears out or the retaining spring is weak.

Luckily these things have the easiest brakes I have ever seen, so it is back-breaking 5 minutes per side.

 

[Fiffa]

The banging noise should go away with the brakes being hit if this is the case. It would normally wear the pads diagonally if the grease wears out or the retaining spring is weak.

Luckily these things have the easiest brakes I have ever seen, so it is back-breaking 5 minutes per side.

Would that depend on how the rears are adjusted in relation to how long ago the system was bled?

 

[TravThePro]

Would that depend on how the rears are adjusted in relation to how long ago the system was bled?

A combination of poorly adjusted rear brakes and bad fluid/air in the brake system would make it so the caliper pistons and drum cylinders would return too far. Normally you will get a poor/slow brake pedal response with squeaky brake noises. More pronounced/long-term use of these circumstances can result in banging noises with super loose pads.

Unless there was already air in the system or the hydrophilic brake fluid (attracts water) picked up a bunch of water, bleeding the fluid would likely not make any difference. Check it with a syringe to see what shape it is in.

I would pick up a laser temp gun to see if there are discrepancies in general heat or an extreme heat spot if you think this is in the brake system or wheel bearings.