Notorious Notorious clanking sound still! 🤬

[AddictedtoRCs]

Well here am I again with the same issue

3 brand new diffs with both front and rear full assembly from Jenny's rc.... Still have a clank sound when near full throttle... Comes and goes as you see I can do some bashing, then it happens then goes away.

2nd full set of diffs now.. I'm stumped.

 

[Senton_Prime]

You try fooling with it on the bench no tires?

 

[Woodentop]

What exactly is happening?

 

[SrC]

If it drives fine regardless of the noise and temps are fine, just have fun with it. The problem will surface and make itself more apparent eventually and then tear it down. Or you can tear all down now. Your call. At times I will just drive it till something fails. Sometimes it will be fine and no issues crop up at all. Make sure the motor pinion mesh is correct for starters. Most important. Seems like you have a shimming issue. Only you know if you did it well enough. And sometimes good enough will have to do. No 2 diffs end up alike. Just have fun and drive it if you feel you went through all the right procedures. These are not precision rigs when it comes to the drivetrains. IMHO. They are bashers. At an equivelent price point to match.

 

[AddictedtoRCs]

You try fooling with it on the bench no tires?

Yea when I do that there's no sound. With or without tires on the bench (in the air) no sound, only when actually driving on a surface

If it drives fine regardless of the noise and temps are fine, just have fun with it. The problem will surface and make itself more apparent eventually and then tear it down. Or you can tear all down now. Your call. At times I will just drive it till something fails. Sometimes it will be fine and no issues crop up at all. Make sure the motor pinion mesh is correct for starters. Most important. Seems like you have a shimming issue. Only you know if you did it well enough. And sometimes good enough will have to do. No 2 diffs end up alike. Just have fun and drive it if you feel you went through all the right procedures. These are not precision rigs when it comes to the drivetrains. IMHO. They are bashers. At an equivelent price point to match.

It's definitely not driving fine if the noise comes and goes immediately within a few seconds. It makes the truck not enjoyable at all. I've already replaced all 3 diffs twice now and both times inspected the diffs prior opening them all teeth fine. In fact all 3 diffs right now on the truck look fine but yet the noise is still there
It's

What exactly is happening?

Making a clanking noise when almost full throttle. Comes and goes. Posting video.






Ok I guess I can't upload video on here. I asked on FB groups with the video posted. If anyone wants to see the video hit me up with a DM on Instagram @AddictedtoRCs

 

[SrC]

The noise you describe is hard to understand.... no noise on the bench means an issue while under load.
You need to isolate where the noise is coming from. Or you will be taking all apart for naught.
Place the rig with Fr wheels on the ground and give some Thr, listen for the noise at moderate brief thr.. Then place the rear wheels on the ground while holding the Fr up, do the same. Does it happen when braking or On Thr or when Coasting?? You will be chasing a ghost at some pint if you don't isolate where the noise is coming from. Try sliding the motor off the pinion letting the drivetrain freespin, and feel for any binding throughout. Just some ideas. We all interpret noises differently. After years of doing this it is more easy to know what normal noises vs issues are. The "Clanking" you describe sounds like maybe you are describing the Dog bones chattering within the Outdrives perhaps??? IDK Maybe normal noises you hear???
Like I stated above earlier, just drive it, if there is an issue somewhere it will surface and fail at some point. That is fine. Maybe the gears need to be bedded in. Maybe it will run just fine for quite a while.
Good luck.

 

[joostin420]

Upload video to YouTube

 

[AddictedtoRCs]

here's the video

https://streamable.com/60prnr

 

[Woodentop]

Can here it clicking slightly, what exactly have you changed on the diff? Mesh good?

 

[AddictedtoRCs]

Can here it clicking slightly, what exactly have you changed on the diff? Mesh good?

mesh is good on all. for today, i added one shim per outdrive on each diff, so F/R diffs each have 2 shims...for the inside i added 1 shim behind the larger planetary gear on both F/R diffs...did the same with center diff...also had to add a shim on center diff outdrive on motor mount...i guess my next step is adding shims on the smaller gears inside the cup itself because i am STILL getting a noise yet within a few seconds I can do a standing backflip...then the noise comes back....

 

[HZRDOS]

Do you have the stock plastic bulkheads? If so, are they rhe same ones that have always been on the truck? If so, maybe an issue with one making an odd mesh between input and crown gear, that under load changes a little. Possible crack in bulkhead?

 

[Woodentop]

Do you have the stock plastic bulkheads? If so, are they rhe same ones that have always been on the truck? If so, maybe an issue with one making an odd mesh between input and crown gear, that under load changes a little. Possible crack in bulkhead?

Precisely what I was going to say, change out the plastic bulkhead for new, sometimes they're just off. For op Have you any slop in the diff if you hold the diff/crowngear itself and pull the outdrive cups in/out? Does the input drive need shimming a little, behind the bearing? Have you checked it with calipers/feelers?

 

[AddictedtoRCs]

Precisely what I was going to say, change out the plastic bulkhead for new, sometimes they're just off. For op Have you any slop in the diff if you hold the diff/crowngear itself and pull the outdrive cups in/out? Does the input drive need shimming a little, behind the bearing? Have you checked it with calipers/feelers?

The entire front and rear diff assembly is brand new. Brand new parts shouldn't be making a noise and need adjustments.

Gonna try full exb housings and diffs next. Unfortunately the rear is out of stock atm

 

[Woodentop]

Full exb housings?? If it was my truck I'd check and lateral play in the outdrives with diff out of the case and shim if needed and check if any shimming is needed on the input drive to start with, cheap and easy.

 

[SrC]

Don't replace with EXB's in haste. work with what you got. Like I said, if performance is ok and there is no binding, drivetrain is freespinning fine, Drive it as is. The noise may even disappear with use as they break-in.
Also, like stated above, one of the Bulkheads may be distorted or have a small hairline crack in it. Under load the diffs can shift or misalign itself. Even with new Bulkheads I have had this problem myself. Need to find where the noise is coming from, Front or Rear. Or go with your gut and start with the one you suspect first. Been there. Sucks to remove a diff that is actually ok, when it was the other one that is bad.

Also, you may be over shimming the internal Sat and Sun gears. Check your BB's at the Hubs. This can also cause noise when they are about to fail, if they haven't already. And the 2 Input cup/gear BB's at the bulkheads are often overlooked at times. We tend to take them for granted. But these BB's get the most load and wear and tear. This can also cause momentary noise Under load and OFF loading, despite how well you shim the Main gear.