Trx-4 sport kit assembly problem

[Buddles]

Hey all! I got my sport kit yesterday and was really stoked. It’s cooler in real life than video. Even in pieces. lol Naturally.

Built the transmission and started on rear axle. But when I installed the pinion gear and spool assembly in the diff the diff output drive seemed to have a small amount of in and out play. Also it wanted to bind a little when I pushed it in. Is there gonna be a washer on the diff output drive the holds it out when I put the drive shafts on? I’m not sure how to explain it all.

I made sure to put enough grease in and not to over tighten the diff cover. This is my first kit and my first crawler so I may be missing something in plain sight. I’ve read and re read the directions tho...


Sent from my iPhone using Tapatalk

[Pushjerk]

Skip ahead and build/install a drive shaft on the pinion output shaft, then give it a twirl. You’ll be way more satisfied. You’ll find little to No play.

I just built this kit last week and was pleasantly surprised there was no shimming needed here as my Axial kits have required. The fit of everything in this Traxxas Kit has been impressive to say the least.

[JC3]

Originally Posted by Pushjerk

I just built this kit last week and was pleasantly surprised there was no shimming needed here as my Axial kits have required. The fit of everything in this Traxxas Kit has been impressive to say the least.

Yup!

[Buddles]

Alrighty. I feel good about that. Got home from work and kept going.

Didn’t get far. Idk if I’m being way to picky or don’t know what I’m doing. When I put the portal housings on the right drive shaft, which is the longer one, it seems 1/16th long. Cause if I put the portal housing on without the driveshaft is turns free. Also the holes don’t line up 100% with the driveshaft in. But I finished it and was turning the diff output and I can feel every gear tooth....

???


Sent from my iPhone using Tapatalk

[Buddles]

Anybody got any ideas? ^


Sent from my iPhone using Tapatalk

[JC3]

Originally Posted by Buddles

Anybody got any ideas? ^


Sent from my iPhone using Tapatalk

Make sure that all of the bearings are fully seated in the covers. Take the suspected bad (long) axle and install it in the portal on the other side, it there is a problem with it, it should transfer over to the other side. Likewise, you can put the good one in the problem portal and examine. You can use this same process of elimination with all of the parts till you find out which one is the problem. Keep track of all of the parts. Tedious but necessary.

[Inspector86]

I doubt this is an issue with the kit. It really sounds like you don't have the axle shaft properly seated in the differential. Take the axle back apart and check for any debris in the axle holes in the diff then re-assemble it following the instructions exactly. If this was an actual part problem we would be hearing about it from everyone building this kit.

[Buddles]

Alrighty. I’ll rebuild it and take my time.

Like you said it’s a small enough difference that it’s bound to be my bad. I’ll report back!

Thanks!


Sent from my iPhone using Tapatalk

[Buddles]

Well I rebuilt and studied each part of the rear axle and still shook my head. So I called traxxas and explained it all. He tried his best but suggested I take it to the hobby shop. Well that’s an hours drive for me but I was willing although I still was scratching my head.

Both rear portals fit in their respective places without either driveshaft but neither portal fit on the right side with the drive shaft and both portals fit on the left side with the drive shaft. So I got to looking at the driveshafts themselves and discovered the “faulty” axle didn’t have as long of flat spot as the “good” one. So I got out my dremel and took care of my own problem.

For my first kit and I wanted to do things right BUT there’s a happy medium. I’ll order a new piece at my leisure now.

Oh it went together better than the front axle and is smoother. Much happy.


Sent from my iPhone using Tapatalk

[JC3]

So I got to looking at the driveshafts themselves and discovered the “faulty” axle didn’t have as long of flat spot as the “good” one. So I got out my dremel and took care of my own problem.

Very impressive fix. Well done sir!

[Inspector86]

Nice dective work! It sounded like the axle shaft was not fully seated but I did not expect the shaft to be the problem. It's pretty rare to hear about a bad part in the TRX4 kits. They had a bad transmission gear early on but that has long since been corrected. I'm guessing this was a one off defective part and you just got lucky and got said part.

[Buddles]

Yeah I actually hope it’s still my bad and not Traxxas fault. But I ordered a new part and we’ll see.


Sent from my iPhone using Tapatalk

[thebigbad23]

Late to the party here but just wanted to add that I had the same two issues with my kit. Filed down one end of the “problem shaft” and she was smooth spinning. As for the output shaft issue I studied it for a while but went ahead and with drive shaft installed it doesn’t seem to be an issue, I’m keeping an eye on it. It wouldn’t have bothered me as much if the front and rear were the same but the front one is tight with no movement.


Sent from my iPhone using Tapatalk