Which Traxxas 2wd transmission case?

[pug]

I am building a speed run Slash 2wd and I need a transmission case.

This looks exactly like the HR case, but half the price, and no branding. It seems like it came out of the same factory. I could also choose between the RPM or Pro-Line case, I just don’t want to spend too much money on it.

 

[TurboChargedHonda]

I have the Hot Racing composite (aluminum motor plate, the casing is plastic, aluminum suspension arm mount) tranny case and have been pretty happy with it so far. The only potential issue I see is that the mount for the rear bumper is a little sketchy, but I don't jump it and don't usually hit the rear bumper, so I haven't had any issues with it.

What you linked appears to be a knock-off of the all-aluminum version (most likely the same except nonbranded), which will be heavier, and make the car more rear-heavy, so be prepared to add some weight on the front to counter it (since you don't want the front to lift off the ground), and re-tune the suspension.

If you are speedrunning I would look into the Proline transmission or the Magnum 272R from the Drag Slash because they come with a sealed differential, so you can tune the diff oil (heavy diff oil makes the car track straighter; the HR and RPM ones do not come with them, so you will have to get the HR sealed differential or a locked spool; I would go for the sealed diff since the locked spool could make the car unstable when turning at high speeds). They are also don't add a lot of weight, which is good, since the Slash 2wd in stock form is a bit rear-heavy for speedrunning.

 

[pug]

I have the Hot Racing composite (aluminum motor plate, the casing is plastic, aluminum suspension arm mount) tranny case and have been pretty happy with it so far. The only potential issue I see is that the mount for the rear bumper is a little sketchy, but I don't jump it and don't usually hit the rear bumper, so I haven't had any issues with it.

What you linked appears to be a knock-off of the all-aluminum version (most likely the same except nonbranded), which will be heavier, and make the car more rear-heavy, so be prepared to add some weight on the front to counter it (since you don't want the front to lift off the ground), and re-tune the suspension.

If you are speedrunning I would look into the Proline transmission or the Magnum 272R from the Drag Slash because they come with a sealed differential, so you can tune the diff oil (heavy diff oil makes the car track straighter; the HR and RPM ones do not come with them, so you will have to get the HR sealed differential or a locked spool; I would go for the sealed diff since the locked spool could make the car unstable when turning at high speeds). They are also don't add a lot of weight, which is good, since the Slash 2wd in stock form is a bit rear-heavy for speedrunning.

Good to know, I will probably be running a 40xx can on 6s, will it even handle 6s?

 

[TurboChargedHonda]

I've only run mine on 2s on a Castle 3800kv motor, so I don't know, but I have seen some people put the VXL 6s motor in it.

 

[pug]

I've only run mine on 2s on a Castle 3800kv motor, so I don't know, but I have seen some people put the VXL 6s motor in it.

I’m looking to put the Arrma 6s motor and esc in it with some pretty high gearing, not exactly sure on the gearing yet.

 

[WickedFog]

If you are doing speed runs, you might want to go mid-motor with it. You basically flip the tranny. But it requires you to cut the chassis bracing to get it flipped. That would get more weight off the rear of the chassis and improve handling and stability at high speeds.

The tranny you linked is definitely a knock-off. It's not even anodized. That is a painted coating on it. I would steer clear of that one, although it may be fine. If it were me, I would consider going with a Pro-Line or actual Hot Racing aluminum trans. But really, I'd probably end up going with the Dragrace Concepts mid-motor trans case.

 

[Greywolf74]

That tranny case should work fine. Its just a clone of the HR one. I have the HR one and thats what I used for speed runs in my Rusty. The RPM and Proline TRanny cases wont work as they do not have open motor plates. You will have to dremel the motor plate to get it to hold a 40xx motor with a large pinion but thats not hard. Also the transmission will hold up to 6S but youll want to repalce the solid pin inside the tranny with a rolled steel pin.

 

[Dan B.]

Good to know, I will probably be running a 40xx can on 6s, will it even handle 6s?

No. Not even close. I have the unbranded aluminum HR case in one of my cars and it’s great except for the rear bumper mount, as stated above. But if you run any kind of power at all it will lunch every factory gear in the truck, as well as rear axles. And I mean right now, as in maybe five minutes run time if you’re gentle with throttle transitions. I run a higher torque motor in that truck and have gone to a spool after scattering three diffs. Spool is great for speed run cars. Robinson Racing hardened gears, Tekno dog bones, now it doesn’t break so much. If you’re going 6s get the ProLine 32p trans. It’s pricey, but I would have saved a lot of money if I’d just done that in the first place. Good luck, and have fun with it!

 

[Greywolf74]

No. Not even close. I have the unbranded aluminum HR case in one of my cars and it’s great except for the rear bumper mount, as stated above. But if you run any kind of power at all it will lunch every factory gear in the truck, as well as rear axles. And I mean right now, as in maybe five minutes run time if you’re gentle with throttle transitions. I run a higher torque motor in that truck and have gone to a spool after scattering three diffs. Spool is great for speed run cars. Robinson Racing hardened gears, Tekno dog bones, now it doesn’t break so much.

If you change the solid pins out for rolled steel pins it will work fine. Thats the only thing I've ever done to my 100+MPH Rustler and I've never had any issues with the transmission. I'm not even running steel dogbones. I'm running the Stock axles. The do tend to break in crashes from time to time but they hold up to running just fine. At least on 1:1 gearing. If you were geared low then you might have been breaking things from over torquing but if you doing speed runs with a 40xx motor theres no reason to be geared low.

If you’re going 6s get the ProLine 32p trans. It’s pricey, but I would have saved a lot of money if I’d just done that in the first place. Good luck, and have fun with it!

How is he supposed to fit a 40xx sized motor in the Proline transmission? He is going to have to have one with an open motor mount plate like the HR or Integy trans cases.

 

[Dan B.]

How is he supposed to fit a 40xx sized motor in the Proline transmission? He is going to have to have one with an open motor mount plate like the HR or Integy trans cases.

You’re right, I didn’t think about that. I still don’t know how some people get away with big power in the 2wd Traxxas stuff without scattering parts. I guess because many go to higher KV motors, so the torque is diminished? Run really crappy tires? Yes, you can do it with speed run only cars, but not for bashing. The truck of mine I referenced is running a 3300kv motor (down from the 3500 VX) and even with that slight torque increase over stock I still risk failures on 3s. Since I went to all hardened steel gears, spool, and steel dog bones it’s a lot better.

 

[Greywolf74]

You’re right, I didn’t think about that. I still don’t know how some people get away with big power in the 2wd Traxxas stuff without scattering parts. I guess because many go to higher KV motors, so the torque is diminished? Run really crappy tires? Yes, you can do it with speed run only cars, but not for bashing. The truck of mine I referenced is running a 3300kv motor (down from the 3500 VX) and even with that slight torque increase over stock I still risk failures on 3s. Since I went to all hardened steel gears, spool, and steel dog bones it’s a lot better.

Yeah for bashing it definitely wouldnt hold up on 6S but speed runs it will hold up which is what the OP was talking about doing. With a Castle 2200kv motor and 1:1 gearing, on road, the tranny isnt being stressed nearly as bad as if it had lower gearing on it and being bashed off road. Well except during wrecks lol