First TF2, drivetrain slop?
 

Hey,

as per title, i just finished assembling my first Trail Finder 2 kit (Mojave), and minus a few teething issues - there were no transmission mounts in my box, instead i had four instead of two standoffs for the leaf springs - i really enjoyed building the chassis.

I am currently in the process of painting (my first shell ever, actually, and looks accordingly but that's on me lol), so i decided to drive a little in between laying the coats.

I'm not sure if i'm overly picky here, i only had two crawlers before (a TRX4 and a Trail King), but the slop in the drivetrain is horrendous? As in, it's so much that it actually properly bothers me and makes me not want to drive the truck because it's frustrating to make it up a small thing and have it fall off the other side until everything engages again.

Now.. I do understand that it's possibly connected to the 2 speed gearbox, which i don't think counts as an excuse considering the TRX-4 also has a 2 speed and zero slop.

My TF2 takes one and a half rotations of the spur gear from forward to get through the slop to reverse. That can't be normal.

In case it is normal, what can i do to fix it? Change to a single speed? Or are there aftermarket gearboxes/drivetrains that fix it? Though the one thing i don't want to happen is to order a new gearbox at considerable expense, to then find out that this too has huge amounts of slop.

The truck is running a 1080 and Crawlmaster Pro 13t, but as mentioned, i can see the spur spin freely 540 degrees before engaging from full forward to reverse/vice versa, so it's not on the electrics side.

Help please, i really like this truck and would love to actually enjoy it. :(

Re: First TF2, drivetrain slop?
 

Get a single speed transmission, much less slop, excess slop is normal for the 2spd.

Sent from my SM-N981U using Tapatalk

Re: First TF2, drivetrain slop?
 

Does that eliminate slop, or just reduce it?

edit: in case people think i'm exaggerating.

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Re: First TF2, drivetrain slop?
 

Honestly, that's better than some t2's I've seen. The single speed has less slop, but I doubt it will reduce it to less than Trx4 levels.

Loose tolerances, its basically a character trait of RC4wd.

Re: First TF2, drivetrain slop?
 

Im working on a way to reduce the amount of backlash by a great deal. Still testing things. But i think it can be almost eliminated.

Re: First TF2, drivetrain slop?
 

my 2 speed tf2 has some slop on it but i figured it be a trait of the tf2 --- and drive it as it is ... makes it a bit more fun and challenging choosing lines carfully if you need to do some precise crawling. I also figured its realistic driving experience where your clutch screams and janks as you give it some gas :lmao:
i guess you gotta live it. :mrgreen:

Re: First TF2, drivetrain slop?
 

Yeah, my single speed Marlin Crawler has a decent bit of "rock back" when I gently nudge it with my finger. I've put two years of hardcore abuse on the rig, and never serviced the transmission once (due to laziness) and it's not really gotten noticeably worse or anything. I think it adds to the charm of the older vehicles the TF2 chassis usually finds itself under the shell of.

Re: First TF2, drivetrain slop?
 

A friend and I have tested a fix and it has reduced slop a great deal. Using quick steel after using a rasp to rough up the surface. Make a pill of quick steel and place it in each hole on the same side and use the shift paw to shape it. The trans engagement has more opportunities to bind before you move and it falls into place. On his rig with a 200 oz servo it hasn’t shown to be a problem. On my setup I used a linkage and dual spring so it’s soft engagement. Would post a pic if I had the means to do so