t maxx trans stripping primary gear

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bullet6599

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I have a t maxx 2.5 which currently is powered by a 3.3. I run the truck for about 3 minutes then the primary gear strips it teeth. Is my problem in the trans or is the problem the slipper clutch? I am new to the hobby so any help is appreciated.
 
I have a t maxx 2.5 which currently is powered by a 3.3. I run the truck for about 3 minutes then the primary gear strips it teeth. Is my problem in the trans or is the problem the slipper clutch? I am new to the hobby so any help is appreciated.
The slipper clutch gear on outside of trans?

I have a t maxx 2.5 which currently is powered by a 3.3. I run the truck for about 3 minutes then the primary gear strips it teeth. Is my problem in the trans or is the problem the slipper clutch? I am new to the hobby so any help is appreciated.
With slipper clutch gears stripping, its usually the engine is where it needs to be. Engine & mounts need to be tight... I've been told u want about enough room between the spur gear & bellhouse gear for a thin piece of paper to fit snugly.
 
The gears in question are inside the trans. Am not sure if the clutch is set too tight
 
The gears in question are inside the trans. Am not sure if the clutch is set too tight
Is there any play in the trans housing where the bearings sit? I never stripped any gears in my 3.3 till i put a lrp30 on it. Now i have Robison racing steel gears... Sux losing reverse tho

Is there any play in the trans housing where the bearings sit? I never stripped any gears in my 3.3 till i put a lrp30 on it. Now i have Robison racing steel gears... Sux losing reverse tho
Maybe bad bearings? The gears in the trans should be set up to where they don't strip, unless a bearing is bouncing around in the housing, or a bearing is messed up

Is there any play in the trans housing where the bearings sit? I never stripped any gears in my 3.3 till i put a lrp30 on it. Now i have Robison racing steel gears... Sux losing reverse tho


Maybe bad bearings? The gears in the trans should be set up to where they don't strip, unless a bearing is bouncing around in the housing, or a bearing is messed up
Maybe have a crack in the trans housing
 
If I remember correctly if using a bigger mill with the 2.5 tranny you have to put the maximum amount of slipper pegs(12 as opposed to the 5 or 6)and tighten the slipper to where it barely moves . If the slipper is too loose it introduces too much shock to the tranny primary gears and pretty much grenades it.
 
If I remember correctly if using a bigger mill with the 2.5 tranny you have to put the maximum amount of slipper pegs(12 as opposed to the 5 or 6)and tighten the slipper to where it barely moves . If the slipper is too loose it introduces too much shock to the tranny primary gears and pretty much grenades it.
Sounds good.. I never had that prob, but early on i got tired of slipper clutch loosening & stripping. I've always had my slipper tight!!
 
The gears in question are inside the trans. Am not sure if the clutch is set too tight
I dont think setting the clutch to tight would do that... Mine is tight as possible. All steel drivetrain. I didnt want to lose power to a slipper clutch spinning

Sounds good.. I never had that prob, but early on i got tired of slipper clutch loosening & stripping. I've always had my slipper tight!!
What dxtreme said could be a possiblity

I'm not a hardcore rc guy... Can only advice u on my experience.. I'm a basher, so i like to make mine do things racers would never do. Jump as hi & far as possible, to where the wind is able to flip u sideways & kill yer rc... Friends i have in hobbie, I'm the tank!! Can run mine over with yer full size truck! Ill drive away, as long as u dont run over my tires
 
Is this your first RC? What are you doing with it when it strips the teeth? Jumping/landing? Driving on concrete/grass/dirt?
 
The only time I stripped my spur gear on my TMaxx was on my 2.5/3.3 hybrid using the OS21TM driving on concrete with the 3.3 wheels. I had an issue with the mesh between my spur and my clutchbell with the motor mount I was using on my web chassis I ended up buying a new motormount that used a spacer for height adjustability and this solved the mesh problem. I just had too much wheel slip on pavement. However this was on the spur and not the transmission. It's possible that you may have to shim the input shaft or the primary shaft or both if it's too loose. I also know that some people have problems with the pin backing off the primary and shearing the gears. You may want to check this out. Even on new kits I always go through everything and rebuild them to make sure it's done right. On a production line not every kit is inspected they only do spot inspection and a lot of the kits get through the line and may not be up to spec.
Is this your first RC? What are you doing with it when it strips the teeth? Jumping/landing? Driving on concrete/grass/dirt?
 
This is my first RC, was givin to me by an uncle as long as I fixed what I broke. I am an ag mechanic during the week, so I have a little mechanic knowledge. My slipper clutch only has 6 pegs, so I think I will just replace the bearings in trans and add remaining pegs. There appears to be no cracks in the case and I was driving on gravel and grass when the gears stripped
 
I actually just signed up to make a thread, as I encountered this issue today. Since this one exists I'll just leave this here and follow your thread.
If I remember correctly if using a bigger mill with the 2.5 tranny you have to put the maximum amount of slipper pegs(12 as opposed to the 5 or 6)and tighten the slipper to where it barely moves . If the slipper is too loose it introduces too much shock to the tranny primary gears and pretty much grenades it.
I'd bet my friend didn't swap to the 3.3 tranny and I did not think to ask. Will find out about this.

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My friend purchased a used 2.5 T-MAXX and converted to a factory new 3.3 a few years ago, but was never able to get the engine running.
I joined him today and got the truck running, and he wanted me to do the break-in, which I agreed to do. Did factory carb set. Engine runs great for now. On light throttle it would lurch forward and stop rapidly. With just a little more throttle it would roll, so I started the break-in process. After behaving for several trigger pulls, it suddenly over-revved and headed off to a fence, where it sat over-revved until I reached it and shut it off. After, would not drive, so we disassembled and found the forward primary transmission gear missing various teeth.
Replaced transmission with a secondary used one. Runs without stuttering. Did break-in tank 1. A little into the second tank, the truck stopped responding and over-revved into a shrub where it had to be killed again. This transmission was also no-drive afterwards.
What would cause this failure in break-in driving conditions?
 
Icarus check the 2 conical washers on the slipper spur gear. The 2 washers go in a particular way. You will notice that they are concave washers and need to be installed like a clamshell. If this is not installed correctly the slipper will not function correctly and induce too much slip. If all is good
Need to tighten the nut until there is no slip at all and back off a 1/4 turn. This should give you a good baseline adjustment on the slipper. You may have to tighten or loosen another 1/3 of a turn either way if even needed.

This is my first RC, was givin to me by an uncle as long as I fixed what I broke. I am an ag mechanic during the week, so I have a little mechanic knowledge. My slipper clutch only has 6 pegs, so I think I will just replace the bearings in trans and add remaining pegs. There appears to be no cracks in the case and I was driving on gravel and grass when the gears stripped
How are your diffs? When your RC propped up on a stand with the tires off the table or bench does the front and rear tires spin when you spin one of the wheels?
 
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This is my first RC, was givin to me by an uncle as long as I fixed what I broke. I am an ag mechanic during the week, so I have a little mechanic knowledge. My slipper clutch only has 6 pegs, so I think I will just replace the bearings in trans and add remaining pegs. There appears to be no cracks in the case and I was driving on gravel and grass when the gears stripped
Id listen to what @DXtreme1... But will say this, my slipper clutch only has 6 pegs, but since its tight as possible, doesn't give me probs, but being tight as possible will twist plastic drive shafts. Only way to run your slipper tight like mine is go complete steel drivetrain. It only takes a min to twist plastic shafts with no real slipper. I know they make a locking slipper nowadays, i think thats a waste, personally. Since my stock 3.3 slipper still works great, even after 10 years of storage
 
I would have to go with the slipper as the issue as well.
 
Trans is currently out of truck, but front and rear diffs are open
 
Trans is currently out of truck, but front and rear diffs are open
Any probs with your diffs? With the front & back diff, make sure u put them back in the correct way. I've screwed up before & didnt. Got it back together & the front wheels went forward, rear wheels went backwards. Just make sure they spin the correct way ehen putting em back together.. All u gotta do is put 1 in upside down to make it go wrong way. My alum diffs werent marked either. So its easy to do.
 
This is good to hear Icarus. I advise to check the slipper pads on the 3.3 tranny from time to time. They tend to be glazed over after awhile and this will induce slip even though the nut is tight. You can sand the glaze down but eventually it will need to be replaced if it gets too thin. Some people recommend the longer aluminum pads. I'm still running the stock ones but once they're spent I'll move up to the upgraded ones to see how that works out.
Rebuilding the slipper with very tight tolerance seems to have solved the issue over here. Thank you guys very much.
 
I hope that's what the issue is and you're running strong! Def stay in touch and let us know how it's going!:thumbs-up:
 
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