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2-speed for TF2?

mcnoco22

Newbie
Joined
Nov 28, 2021
Messages
2
Location
Wellington
I installed an RC4WD 4:1 compact gear reduction unit on my TF2. It's AWESOME for crawling, but way too low for general trail driving. What's the best option for getting a higher gear ratio while retaining the crawling ability of the lower gear ratio? Is there a 2-speed transmission comparable to the AX2 that works well with the TF2? Larger pinion? 2-speed T-case? This should probably go in the newbie section, but most of my efforts so far have been put into making my rigs a scale as possible:lol:.
 
https://store.rc4wd.com/R3-Scale-2-Speed-Transmission_p_2220.html

This tranny came in select models of the TF2. Out of stock right now, but im sure you can find ebay takeouts.

I have heard these trannys are known for having quite a bit of slop compared to their single speed. I have no first-hand experience so that could just be RC4WD haters spewing their opinions.

______________________________________
AR60 VS410
TRX4 Sport
coming soon..

Veterans deserve a whole month too...
 
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I run the 2 speed trans and yes there is a lot of slop in it from how it shifts. There are mods you can do to tighten it up, but not worth it... if you plan ahead on the trail its manageable.
 
I run the 2 speed trans and yes there is a lot of slop in it from how it shifts. There are mods you can do to tighten it up, but not worth it... if you plan ahead on the trail its manageable.

If you're handy enough, modding the internal shift paws to remove the large area that causes slop is totally worth it. 90% of the slop in the TF2 equipped with the 2 speed comes from there. The rest comes from all the other contact points in the drivetrain. Driveshaft yokes, where the axles meet the diff, transfer case etc.

But removing the biggest offender to slop in the 2 speed? totally worth it if you have the knowhow.

I'm going to take the plunge and do it at some point. Ill post it when I do.

I too remember seeing a post on here showing how to fix it, But can't find it now ironically.
 
If you're handy enough, modding the internal shift paws to remove the large area that causes slop is totally worth it. 90% of the slop in the TF2 equipped with the 2 speed comes from there. The rest comes from all the other contact points in the drivetrain. Driveshaft yokes, where the axles meet the diff, transfer case etc.

But removing the biggest offender to slop in the 2 speed? totally worth it if you have the knowhow.

I'm going to take the plunge and do it at some point. Ill post it when I do.

I too remember seeing a post on here showing how to fix it, But can't find it now ironically.


I get it, I should have been more clear. In this great state of Delaware, our biggest hill here is a leaching field... I do alot of shifting. When filling the gaps of the driven gear I found that it would miss from time to time.. great poss that was my fault in fill too much.. but I would loose momentum in the mud. The slop reminds me of my old Yj with a lunchbox in it, having a ton of slop.
 
I get it, I should have been more clear. In this great state of Delaware, our biggest hill here is a leaching field... I do alot of shifting. When filling the gaps of the driven gear I found that it would miss from time to time.. great poss that was my fault in fill too much.. but I would loose momentum in the mud. The slop reminds me of my old Yj with a lunchbox in it, having a ton of slop.

Adding a bevel to the inside edges of the material leading to the depression that the paw grabs would alleviate that 99% of the time, along with leaving just a little slop in the slot would be perfect. Thats how I'm gonna do it.

I live in Florida so I too only have a few rocks in the entire state. So I feel you there. But when I do get on the rocks in first gear and the slop hits on a descent, and it topples end over end or screws up my chance at that line, is quite frustrating.

I'm building mine for both trail and crawling, so refuse to get rid of the 2 speed. I'm pretty sure from an engineers standpoint, adding the bevels will force it to catch even shifting at speed. Give it a little room for it to solidly engage and there should be very little slop and no missed shifts. A slight difference in the angle of the bevel from one side to the other will also prevent it from from skipping back out at high rotational speed.

When i get around to it; That is the question haha
 
Adding a bevel to the inside edges of the material leading to the depression that the paw grabs would alleviate that 99% of the time, along with leaving just a little slop in the slot would be perfect. Thats how I'm gonna do it.

I live in Florida so I too only have a few rocks in the entire state. So I feel you there. But when I do get on the rocks in first gear and the slop hits on a descent, and it topples end over end or screws up my chance at that line, is quite frustrating.

I'm building mine for both trail and crawling, so refuse to get rid of the 2 speed. I'm pretty sure from an engineers standpoint, adding the bevels will force it to catch even shifting at speed. Give it a little room for it to solidly engage and there should be very little slop and no missed shifts. A slight difference in the angle of the bevel from one side to the other will also prevent it from from skipping back out at high rotational speed.

When i get around to it; That is the question haha

Yeah I agree the 2 speed is great, I like the idea to bevel the edge into the slot just watch about reverse. As far as a design I'm surprised they went with an idea like this, unless it's for production and cost... I'm in the marine world and always hated the clutch dog idea in the lower unit untill seeing the strength and simplicity of it.
 
Yeah I agree the 2 speed is great, I like the idea to bevel the edge into the slot just watch about reverse. As far as a design I'm surprised they went with an idea like this, unless it's for production and cost... I'm in the marine world and always hated the clutch dog idea in the lower unit untill seeing the strength and simplicity of it.

I was actually thinking about this yesterday.

Since you wouldn't be shifting full speed in reverse, a difference between the bevel angle from one side of the slot to the other, one higher than the other should help it catch, and prevent jumping out shifting at speed while going forward.

This might work.
 
Go for it.... See what happens.... I'd be interested to see how it reacts

I'll be going for it after USTE this year. Don't wanna tear up the truck before then and wind up rushing it back together.

I've got the basic design planned out. Just need everything apart and in front of me to get it all finalized.
 
I'll be going for it after USTE this year. Don't wanna tear up the truck before then and wind up rushing it back together.



I've got the basic design planned out. Just need everything apart and in front of me to get it all finalized.
So in the past weeks or so I've pull my truck apart a few times and the trans... I've found in my case alot of the slop was coming from A: too small driveshaft pins, and B: holes in the shafts stretched open. I have the trans pack full of Soo much marine grease I'm barely getting much slop in the trans.. I've switched over to all 3mm screws in all of my d-shaft pins and that cleaned up alot...

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