Transmission clicking
 

Hey guys, I've been hearing this clicking from the transmission for a while now, but it has gotten louder. The weird part is only under a load does it do it. Drive it on flat or in the air it doesn't do it. Start a step climb and you hear it. I pulled out
Trans and could recreate the sound. Just not as loud. So I pulled apart the transmission last night. Just to find it looking just like it did last time I had it apart. I did notice there being some slop in the shafts tho. Maybe time for new bearings??? Any thoughts on this clicking transmission? Should I get a bearing kit? Which bearings should I buy? Thanks in advance for any advice"thumbsup"

Re: Transmission clicking
 

Checking the simplest thing first, make sure the set screw on you motor pinion gear isn't hitting your spur gear if they are out of alignment.

Otherwise, I typically buy 10 packs of bearings in the various sizes I need. Available on Amazon (but there might be some wait time for shipping these days).

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Re: Transmission clicking
 

Thanks brother! Motor wasn't attached when I recreated the sound with the trans in my hand. So that can't be the issue. I know from my skateboarding days that buying good bearings is worth it. I rather spend good money on ones I don't have to replace often. Thanks again tho!

Re: Transmission clicking
 

Fast Eddy makes some of the best. They have a standard bearing kit for about $42, and a ceramic bearing kit for $142 (not sure if the ceramic kit has stainless races or not, they don't specify on their site)

I know you can find some stainless bearings if you pick and choose online. I find my bearings usually fail due to corrosion (water gets in and can't get out, destroying the cages) rather than wearing out or seal intrusion by dirt.

https://www.fasteddybearings.com/tra...d-bearing-kit/

https://www.fasteddybearings.com/tra...d-bearing-kit/

https://www.amazon.com/dp/B00FY4XP0O..._-CyEEb5PV43XF

Good Luck!

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Re: Transmission clicking
 

Make sure your driveshaft are lined up properly

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Re: Transmission clicking
 

That’ll make the trans click? I didn't have the drive shafts on when I tested it in my hand.

Re: Transmission clicking
 

Mine is noisy too, and has a click but when I tore the transmission and axles down I didn’t find anything wrong so I just re-greased and closed it back up. Have you noticed any issues slow crawling smoothly?

Sometimes I think these are just loud, metal gears and all, but bearings is a good idea. I second fast eddy as I’ve used them on a few rigs with no issues.

If bearings help you I may follow suit. "thumbsup"

Re: Transmission clicking
 

Was just guessing.. I had a click and I redid the motor and gear mesh, and noticed I didnt have the shafts balanced. The click went away lol

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Re: Transmission clicking
 

Mine crawls just fine. I haven't noticed any issues with performance. Just that clicking drives me nuts. I'll probably give a new set of bearings a try. I'll let you know if it helps.


I might try reassembling the trans making sure the shafts in the trans are both facing the same way. That might do it. Who knows lol!

Re: Transmission clicking
 

Haha right! I though it was cool that the shafts balance that way. Kind of like really trucks. When my rear driveshaft bearings went in my jeep, it made some interesting noises lol

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Re: Transmission clicking
 

Haven't been able to pick bearings yet but decided to try out reassembling the trans and making sure everything was in the right position. That did did the trick! No more clicking!!! So for sure the shafts inside the trans need to be in sync. I will try it on the rocks this evening, but bench test went great! Thank you guys for the help and advice!!!

Re: Transmission clicking
 

Looks like I got a side project on my hands when I rebuild the rex again.

Glad it worked out with just some tooling "thumbsup"

Re: Transmission clicking
 

Awesome! What shafts am I looking for inside the tranny? My TRX-6 does this & it has gotten louder & louder. It drives me nuts since rock climbing echoes it hahaha.

How did mine get out of sync? I’ve never had it apart.

Re: Transmission clicking
 

The shafts that the drive shaft attaches to. Holes on the front and rear shaft should be in the exact same position. Same goes for the driveshafts themselves. Should be able to remove all 4 driveshaft pins without spinning the driveshaft. Don't know how it could be out of sync unless it was assembled wrong from factory. Have you removed the driveshafts at any point?

Re: Transmission clicking
 

Yea, the tranny rear output shaft is 90* out then. And my center diff is out like 45*. Both are easy to fix, but a pain.

Is this correct? All 6 pins (TRX-6) should line up as you said. So it was assembled wrong. Wow, must 1 in a billion chance LOL 😂

Re: Transmission clicking
 

Alright, that did it! It feels like it has a hint less drivetrain slack, as well. I realigned the transfer case outputs & the center diff pinion to get it all synced.

I appreciate the details!

Transmission clicking
 

Thanks guys!!

My new Sport showed up Friday and I’ve had the clicking since first outing.

I thought the clicking was a molding imperfection on the skid rubbing on the front drive shaft.

I took the front drive shaft off and used a soft dremel polishing tip on the skid.

Still have the clicking.

Found this thread this morning and sure enough.

Thanks again!!!!
https://uploads.tapatalk-cdn.com/202...38d4a346ac.jpg

ETA - since I’m going to be taking the trans apart would it be a benefit to upgrade to the aluminum transmission housings I’ve seen?

Thanks

Re: Transmission clicking
 

Benp- I don't think it's necessary to replace the transmission housing with an aluminum one. The majority of people are still using the stock plastic housing with no issues. I wouldn't spend the money unless you have a reason to justify it.

Re: Transmission clicking
 

Replacing the driveshafts with MIP driveshafts also eliminates this issue. They are 30% slimmer than the stock.

Re: Transmission clicking
 

I finally went ahead & replaced the tranny with an aluminum one from GPM. So now I’m 100% metal except the fenders, Bowhouse battery tray, Proline lightbar, and body on my TRX-6... only took about $3000 total lol (actually, I stopped keeping track @ 3 grand). I had a few parts custom made on a CNC, but most are either Samix or GPM otherwise. Weight is 12 pounds 5 ounces with battery/body and that’s with titanium and aluminum everywhere possible (brass on axle bits).

Anyway, that aluminum GPM tranny did the trick & now I have ZERO clicking. The entire drivetrain is FAR more quiet than stock with less slack AND RESISTANCE, as well. The metal parts (tranny, motor cover, motor mounting plate, the 2 part 8238 where the tranny/everything mounts to (both parts are 8238?)) fit PERFECT and now the rig is silent on the trail.

In fact, the minimum startup speed is even slightly lower and throttle modulation is a tad more responsive.