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2 speed with 2wd\4wd?

350TacoZilla

Quarry Creeper
Joined
Sep 29, 2007
Messages
217
Location
Hancock MD
Is there such a thing thats commonly available and maybe doesn't cost a fortune?

I always liked the idea of having a high and low trans but also being able to go 2wd for some donuts and such.
 
Least expensive that is know of would be the Traxxas TRX-4. It's available in numerous RTR forms, each work a different body and/or body color. Additionally, it's available in at least two different kits, one of which includes ALL electronics...but, you have to supply a body. This particular kit includes one standard servo for steering, plus 3 micro servos - one for the hi/lol trans, the other two for the front & rear locking diffs.

This might be your only option...but, even if it's not, it's probably your best option.


~ More peace, love, laughter, & kindness would make the world a MUCH better place
 
Following. I’d love to have this setup in my current & next scale build.

And to go 1 step farther, I think it’s be cool to have Remote locking rear diff, 2WD/4WD AND a 2speed. Probably asking too much but it would definitely be cool. I’m not even sure if you could fit that all in one transmission readily available on the market right now.

[mention]Panther6834 [/mention] how do you do 2WD/4WD on a TRX4 trans? I need to know for research purposes…lol
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Cheapest option would be pieced together. I hear the 10.3 2spd isn't geared as nice as the TRX4, but you can do a 10.3 kit, convert the axles to AR44 and buy the SSD front locking hubs ($550+) or vice versa (buy 10.2 instead and get 2spd trans).

TRX4 is the more solid choice, but you'd lose the diff locking setup if you converted to AR44 axles to utilize the SSD locking hubs as well ($600+).

Either way would also require custom links ($70+).

If there was already such a kit out there that's inexpensive, I would already have completed one lol.
 
And to go 1 step farther, I think it’s be cool to have Remote locking rear diff, 2WD/4WD AND a 2speed. Probably asking too much but it would definitely be cool. I’m not even sure if you could fit that all in one transmission readily available on the market right now.

[mention]Panther6834 [/mention] how do you do 2WD/4WD on a TRX4 trans? I need to know for research purposes…lol
Short answer: Read up on the TRX-4

Long answer: Not everything is in the trans. Additionally, at least a 5-channel Tx/RC is needed (which IS included in the package), for the following channels: 1 for steering, 2 for ESC/motor, 3 for hi/lo, 4 for front locking diff, and 5 for rear locking diff. However, if you want a Tx-controlled winch and/or other accessories (ie. lights), you'll need even more channels.

The hi/lo is lever-actuated. Inside the trans, there are two sets of gears, and the servo controlling the lever slides a toothed-ring back & forth, allowing one set of gears to rotate the outdrives at a time. As for the diff locks, they operate very much like 1:1 locking diffs (unlike the SSD mentioned, below).

For each micro servo operating the mechanism inside each diff, the servo pulls/pushed a cable, which, in turn, moves the lever inside, which in turn slides a toothed-ring similar to the one inside the trans. However, instead of sliding that ring back & forth between two sets of gears, it's engaging & disengaging the diff from the diff's outdrives. This allows you to operate a TRX-4 as a 4x4, RWD, and FWD.

Cheapest option would be pieced together. I hear the 10.3 2spd isn't geared as nice as the TRX4, but you can do a 10.3 kit, convert the axles to AR44 and buy the SSD front locking hubs ($550+) or vice versa (buy 10.2 instead and get 2spd trans).

TRX4 is the more solid choice, but you'd lose the diff locking setup if you converted to AR44 axles to utilize the SSD locking hubs as well ($600+).

If there was already such a kit out there that's inexpensive, I would already have completed one.

There IS already "such a kit out there"...the TRX-4 Scale Trail Rock Crawler Assembly Kit (82016-4-R6), which is $399 (I picked mine up 2wks, at NorCal Hobbies, for $389)...and, the only approval thing needed is a body. Sure, prior can go the SSD locking hub route...and throw a LOT of money down the toilet...but, there is NO need to.

I'm not saying SSD is bad. SSD makes excellent products, most of which are very reasonably priced...but, to me (and many others), adding AR44 Axles, and the SSD locking hubs, to a TRX-4 ISS complete waste of money...especially for someone just purchasing a TRX-4. Now, of you already have a TRX-4 with AR44s, and you looking up 'upgrade' it, then, yeah, I could see the possibility of getting the SSD locking hubs.

Bodies can be fine cheaply...especially if you buy one used. To start, a person doesn't *need* a new body...there's nothing wrong with building a TRX-4 Chassis Kit, and sticking a used body on it. You can find bodies as cheap as $25. That, plus the chassis kit, and you've for yourself one of the best trail crawlers...all for about $450 (incl tax). For an RC vehicle, that IS on the inexpensive side. So, my question to you to(based on your last sentence) is, "Why haven't you completed one?"

Truth is, in regards to the one I'm building, I'm not even building it for me. I bought it just because I enjoy building kits soooo much (I'm also simultaneously building a Tamiya CC-02 Mercedes Unimog w/ Tamiya Track Units, and a Tekno MT410). After I finish it, I'm going to give it to my stepdad.


~ More peace, love, laughter, & kindness would make the world a MUCH better place
 
I'm very much a newb and didn't research on how to make a TRX4 remotely convert to 2wd yet but it sounds like it's as easy just purchasing the kit? I already have one but just asking for more info on such a conversion.
 
Short answer: Read up on the TRX-4

Long answer: Not everything is in the trans. Additionally, at least a 5-channel Tx/RC is needed (which IS included in the package), for the following channels: 1 for steering, 2 for ESC/motor, 3 for hi/lo, 4 for front locking diff, and 5 for rear locking diff. However, if you want a Tx-controlled winch and/or other accessories (ie. lights), you'll need even more channels.

The hi/lo is lever-actuated. Inside the trans, there are two sets of gears, and the servo controlling the lever slides a toothed-ring back & forth, allowing one set of gears to rotate the outdrives at a time. As for the diff locks, they operate very much like 1:1 locking diffs (unlike the SSD mentioned, below).

For each micro servo operating the mechanism inside each diff, the servo pulls/pushed a cable, which, in turn, moves the lever inside, which in turn slides a toothed-ring similar to the one inside the trans. However, instead of sliding that ring back & forth between two sets of gears, it's engaging & disengaging the diff from the diff's outdrives. This allows you to operate a TRX-4 as a 4x4, RWD, and FWD.



There IS already "such a kit out there"...the TRX-4 Scale Trail Rock Crawler Assembly Kit (82016-4-R6), which is $399 (I picked mine up 2wks, at NorCal Hobbies, for $389)...and, the only approval thing needed is a body. Sure, prior can go the SSD locking hub route...and throw a LOT of money down the toilet...but, there is NO need to.

I'm not saying SSD is bad. SSD makes excellent products, most of which are very reasonably priced...but, to me (and many others), adding AR44 Axles, and the SSD locking hubs, to a TRX-4 ISS complete waste of money...especially for someone just purchasing a TRX-4. Now, of you already have a TRX-4 with AR44s, and you looking up 'upgrade' it, then, yeah, I could see the possibility of getting the SSD locking hubs.

Bodies can be fine cheaply...especially if you buy one used. To start, a person doesn't *need* a new body...there's nothing wrong with building a TRX-4 Chassis Kit, and sticking a used body on it. You can find bodies as cheap as $25. That, plus the chassis kit, and you've for yourself one of the best trail crawlers...all for about $450 (incl tax). For an RC vehicle, that IS on the inexpensive side. So, my question to you to(based on your last sentence) is, "Why haven't you completed one?"

Truth is, in regards to the one I'm building, I'm not even building it for me. I bought it just because I enjoy building kits soooo much (I'm also simultaneously building a Tamiya CC-02 Mercedes Unimog w/ Tamiya Track Units, and a Tekno MT410). After I finish it, I'm going to give it to my stepdad.


~ More peace, love, laughter, & kindness would make the world a MUCH better place


LOL! do you even know what your talking about?

A locking/unlocking diff is totally different than a 2WD and 4WD shifter. A 2WD/4WD shifter completely shuts off power to the said axle. When you go into 2WD, it sends 0 power to front axle, allowing to spin freely while rolling. When you go into 4WD, it sends power to both axles.

When you unlock a diff, it still sends power to that axle, but when one tire is under load it will stop power to that tire, leaving the other one not under load spinning. When you have both diffs unlocked your still in 4WD, but with open diffs that won’t continue to work together under load.

So, there’s is NOT such a transmission in 1/10th scale that will have remote locking diffs, 2WD/4WD shifter and 2speed. (That I’m aware of)

I think you need to learn more about how diffs work then come back with your snarky comments/remarks when you’ve gained the correct knowledge[emoji6]





Sorry OP for this non-sense, let’s get back to your question. I actually found an interesting video on the TRX4 where a guy modified the front driveshaft to have a sliding mechanism where you can manually lock/unlock 4WD. This gives you 2 speed, unlocking diffs and 2WD. Granted, it isn’t a remote 2WD switch, but it does work for $30. He walks you through it and shows you the parts you need if you want to try it out[emoji1687]

https://m.youtube.com/watch?v=UxJmk2jcp_Q


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the vanquish something twin bla bla bla has atleast the 2wd-4wd option i dont remeber if its 2peed or has dig but but a good brushless system will make up for the 2 peed trans
the new trans comes in the new phenox kit or you can buy it seperatly

no 2 speed but here it is
https://www.vanquishproducts.com/vfd-twin-transmission-kit/
 
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The closest and best option (imo) is using a vfd twin, the selectable o/d function can be set with a 3 position switch to stop in the neutral position and only send power to the rear wheels. It does not have a 2 speed though.

The vfd twin comes in the vs410 Phoenix kit, but can be added to any vs410 kit, or any custom vehicle that utilizes a vfd style trans.

A 2 speed is unnecessary with a good brushless system like a mamba x and 2850kv slate motor. Even on 3s my Phoenix has more than enough speed to end up on the roof consistently [emoji23]


Sent from my iPhone using Tapatalk
 
I'm very much a newb and didn't research on how to make a TRX4 remotely convert to 2wd yet but it sounds like it's as easy just purchasing the kit? I already have one but just asking for more info on such a conversion.

No "conversion". Work front & rear diffs 'locked', vehicle operates as 4x4. Unlock the front diff (rear diff locked), and it operates as a RWD. Unlock the rear diff (front diff locked), and it operates as FWD. Put each servo on it's own channel (as described in my last post), and you independently control the front & rear locking diffs. Sand goes for the hi/lol trans (ie. the 5th channel).

LOL! do you even know what your talking about?

A locking/unlocking diff is totally different than a 2WD and 4WD shifter. A 2WD/4WD shifter completely shuts off power to the said axle. When you go into 2WD, it sends 0 power to front axle, allowing to spin freely while rolling. When you go into 4WD, it sends power to both axles.

When you unlock a diff, it still sends power to that axle, but when one tire is under load it will stop power to that tire, leaving the other one not under load spinning. When you have both diffs unlocked your still in 4WD, but with open diffs that won’t continue to work together under load.

So, there’s is NOT such a transmission in 1/10th scale that will have remote locking diffs, 2WD/4WD shifter and 2speed. (That I’m aware of)

I think you need to learn more about how diffs work then come back with your snarky comments/remarks when you’ve gained the correct knowledge.

First, the only one making 'snarky' comments is you. If you reread what I said, without any attitude in your brain, you realize I was attempting to provide helpful information. In what I said, where did I mention anything about "2WD/4WD shifting"? Oh, wait, I didn't. Also, I know EXACTLY how a locking diff works in a 1:1 vehicle (which is what you described), and how one can, essentially, achieve the same kind of operation on a TRX-4 (what I described). If, based on what I said in my previous comment, you can't figure that much out...well, maybe you still have a few things to learn about RC.

As for the mod mentions in the video link you posted, that's all in great...but, it is NOT remotely controllable. You, literally, have to stop the vehicle, flip it over, manually switch it between 2WD & 4WD, put the vehicle back over, and then go about your running. Although the TRX-4's locking diffs don't operate 'electronically' the same as a 1:1 vehicle, it is still possible to approximate the same type of operation...which IS the point I was trying to get across.

Finally, you're still going on about everything being in the transmission. Again, this is not a 1:1 vehicle, and, obviously, as I VERY CLEARLY stated, only the 2-speed shifting is contained within the trans. The servos for the front/rear locking diffs may be located next to the trans, but they are 100% operating mechanics inside the axles, NOT in the trans...which is something else I was very clear about in my previous comment.

Just because a scale RC vehicle is designed to 'look' line a 1:1 vehicle does NOT mean it operates the same way...obviously, it doesn't, now was it ever intended to. Scale RCs are *not* the same as their real-world counterparts...they are not, and never were, designed to function in the completely same way. Obviously, design changes are required, as are operational changes. If you, honestly, expect scale RCs to function 100% identical to their real-world counterparts...well, I feel sorry for you, because that's never going to happen. And, that's all I have to say on the subject.

To the Op, I hope you figure out how to go about getting everything working, as I previously described. If you need additional help, please, feel free to PM me, and I will provide whatever assistance I am capable of...and, for anything I do not know, I will admit I don't know, but will also try to direct you to someone (whom I trust) who does know. At the same time, you would also always be able to call Traxxas support. They have always provided outstanding support & answers to any problems I've run into on any of my Traxxas vehicles. With that said, I will now be unsubscribing for this thread. The 'snarky' negativity from others has me no longer wanting to participate in this thread. It is, obviously, not your fault. Whatever you decide to do, I wish you the best of luck...and, welcome back to the wonderful world of RC. [emoji1688]


~ More peace, love, laughter, & kindness would make the world a MUCH better place
 
where did I mention anything about "2WD/4WD shifting"? Oh wait, I didn’t.


No "conversion". Work front & rear diffs 'locked', vehicle operates as 4x4. Unlock the front diff (rear diff locked), and it operates as a RWD. Unlock the rear diff (front diff locked), and it operates as FWD.



l

This allows you to operate a TRX-4 as a 4x4, RWD, and FWD.


Oh, okay.


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Yeah, that's not 2wd.
I'm not the one who's "mixed up". First, I'm not the one who used the term '2WD'...I specifically said 'FWD' and 'RWD'. Second, since when is FWD, or RWD, not the same as '2WD'...FWD is the same as 2WD, and RWD is the same as 2WD...but, again, I'm not the one who (in this thread) made the initial reference to '2WD'.

Read back to my initial post, and you'll see I was simply answering the Ops question, workout having gone on some tangent that has to do with 1:1 vehicles, as opposed to RC vehicles (as the Op asked about).


~ More peace, love, laughter, & kindness would make the world a MUCH better place
 
I'm not the one who's "mixed up". First, I'm not the one who used the term '2WD'...I specifically said 'FWD' and 'RWD'. Second, since when is FWD, or RWD, not the same as '2WD'...FWD is the same as 2WD, and RWD is the same as 2WD...but, again, I'm not the one who (in this thread) made the initial reference to '2WD'.

Read back to my initial post, and you'll see I was simply answering the Ops question, workout having gone on some tangent that has to do with 1:1 vehicles, as opposed to RC vehicles (as the Op asked about).


~ More peace, love, laughter, & kindness would make the world a MUCH better place


Well the op said 2wd first. Which most of us interpreted (correctly imo) to mean power to the rear axle only.

1:1 or not, 4WD with two open diffs does not make a 2WD, FWD, or RWD.

I can agree though, unlocking the front diff on a trx4 does make it behave more like a rear wheel drive, but that’s still 4WD.


Sent from my iPhone using Tapatalk
 
Well the op said 2wd first. Which most of us interpreted (correctly imo) to mean power to the rear axle only.

1:1 or not, 4WD with two open diffs does not make a 2WD, FWD, or RWD.

I can agree though, unlocking the front diff on a trx4 does make it behave more like a rear wheel drive, but that’s still 4WD.


Sent from my iPhone using Tapatalk
I never said the TRX-4 was the "perfect" solution...but, it's about as close as anyone will come for an "out of box" experience.

However, going back to something both you & Ferp mentioned...but, it is NOT 'inexpensive'...would be the Vanquish VS4-10 Phoenix. It doesn't have a 2-speed be trans, but it does have remotely-selectable 2-speed OD, and a DIG. One can set up the DIG as a 3-position, with the 'middle' being a freewheeling-rear, thus turning out into a true 2WD w/ FWD. By combining the selectable OD, and a freewheeling rear end, you, essentially, turn it into a 2-speed FWD...but, when on 4x4, it's only single-speed (albeit, with selectable OD).


~ More peace, love, laughter, & kindness would make the world a MUCH better place
 
Wow things got busy in here while I was gone. To answer the question of what I meant I did in fact mean more like a "common" 1:1 4x4 truck where you can choose 2wd sending power only to the rear or being able to select 4wd sending power to both front and rear axle. I included the "common" in there because I'm sure somewhere in the world there is a truck that when in 2wd is actually Front wheel drive.

In looking all of about an hour or two with this subject I have seen few 2wd to 4wd switchable transmissions and also plenty of 2spd transmissions but nothing that included both. I at first thought about something like a trx4 transmission with a dig unit mounted backwards but those lock the non powered axle so that would get me more of a drag race line lock than 2wd-4wd shifting.
 
I liked 2wd with my VFD Twin at first, but without being able to unlock the front diff, it gets old pretty quick... doesn't want to turn at all. I briefly looked into a TRX4 front axle with portal delete to be able to unlock the front diff, but... **** traxxas.:flipoff:
 
technicly speaking panther is right if only 1 front wheel is spinning and 1 rear wheel is spinning it would
in fact be 2wd
i dought thats what the op ment though and the trx4 isent that truck although the vanquish trans on a trx4 would be awsome
 
Og Bruiser transmission had that feature iirc. A Losi comp crawler transmission can be converted to front/four/rear wheel drive ttansfer case.
 
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