new2rocks Guide to the TRX-4

[92fox]

I'm new to the RC hobby, and newer to crawling. I bought the TRX4 mainly because I know the Traxxas name won't disappoint, and this thread has been a Godsend. So much useful information in here.

All I've done to mine so far (3 weeks now) is take the portal and diff covers off to lube them up, change the oil in the shocks to 15wt, and play super hard with it (at least 30 battery packs run through it) without a single problem. Love this truck, and my boys (5 and 6) love it and have been super hard on it as well. I know something will eventually break, but so far it's a lot more durable and fun than my Traxxas Slash, and I can give the controller to my kids without fear because it tops out at abou 10mph.

Thanks so much for this thread...there are several others on this forum as well, but this one has helped the most.

[new2rocks]

Originally Posted by 92fox

I'm new to the RC hobby, and newer to crawling. I bought the TRX4 mainly because I know the Traxxas name won't disappoint, and this thread has been a Godsend. So much useful information in here.

Thanks so much for this thread...there are several others on this forum as well, but this one has helped the most.

Welcome to RC, RCC and crawling, and thanks for the kind words! Glad to hear you're enjoying your TRX-4 so far (it's a great truck) and that you've found the guide helpful. Also glad to hear you're getting the kids involved. It's so much more fun with family involved.

[tuanies]

Lots of great info here. I've been staring at my shopping cart at RPP Hobby, ready to click buy.

Any thoughts on running a 550 brushless motor, like the Team Brood Vigor 550 2000kv? Would it be overkill?

[CODYBOY]

Originally Posted by tuanies

Lots of great info here. I've been staring at my shopping cart at RPP Hobby, ready to click buy.

Any thoughts on running a 550 brushless motor, like the Team Brood Vigor 550 2000kv? Would it be overkill?

Imo it would be more motor than you need, I'm sure it would work but not sure how friendly it would be to your drive train.
Ernie

[tuanies]

Originally Posted by CODYBOY

Imo it would be more motor than you need, I'm sure it would work but sure how friendly it would be to your drive train.
Ernie

That's what I'm concerned with. I have an 1/8th scale setup in my SCX10 II - its overkill, but insanely fast lol.

[Inspector86]

Are you going for "insanely fast" speed? Why?

[tuanies]

Originally Posted by Inspector86

Are you going for "insanely fast" speed? Why?

Not with a TRX-4 - it'd be a crawler that I can run through the river and mud. The SCX10 II is my U4RC 1.9" solid car.

[new2rocks]

Originally Posted by CODYBOY

Imo it would be more motor than you need, I'm sure it would work but not sure how friendly it would be to your drive train.
Ernie

Agreed. The only reason for a 550 brushed instead of 540 brushed is to handle the tall top gear ratio. A good 4-pole 540 brushless will have plenty of torque to handle the gearing, and with a low kv (e.g. 2200) 540 can, top speed is already giddy.

[BoyFreakWonder]

I stuffed a 3500kv hobbystar pro4 in mine and I am very happy with the results on 3s.

[new2rocks]

It's time for some updates. Started with the intro to add info on the new Bronco and kit versions. More updates to come...

[new2rocks]

Added new section 2 with performance upgrade recommendations and updated axle section to discuss portal delete option.

[AggressorBLUE]

In the performance section, you note on behalf of HH:
"Holmes Hobbies offers the TorqueMaster Pro 550 in 21T and a limited edition 30T. They also offer the Crawlmaster Pro 550 (which is a 5-slot design) in 10T and 12T flavors, which would be comparable to a 21T and 27T 3-slot motor, respectively"

Any thoughts on how much it will impact performance to go with those motors that are not reverse turn, like the stock motor?

PS: why is this thread not stickyed yet?

[svt923]

Originally Posted by AggressorBLUE

Any thoughts on how much it will impact performance to go with those motors that are not reverse turn, like the stock motor?

There is no performance impact if your motor rotation is set properly. If you are running with no advanced timing (most sealed can motors), just swap the leads and the motor will change directions. If you are running advanced timing on your motor (most open endbell Holmes motors come at 6* of timing), remove the endbell and rotate it 180* to reverse the rotation and maintain proper timing. Also make sure your ESC is running in the proper direction since many can provide more amps in forward as they do in reverse.

You can also specify what timing and direction you want when ordering directly from Homes.

[Stonewall]

New2rocks, what an awesome write up! Thanks for all the effort you put in!

[treadway47025]

Which model is that manual included? My bronco came with very little info/lack of a manual other than start up

[number9]

Started putting my kit together the other night and found my trans gear to be undersized as well, if you need another data point.

[Cesco]

First of all, what a great topic!

Suggestion for updating 4. Motor and ESC.

Holmes Hobbies offers the TorqueMaster Pro 550 in 21T and a limited edition 30T.

I do not know if that's changed, but I do not see the Torquemaster 30T on The Holmes Hobbies website.

In the page MOTOR RECOMMENDATIONS you can find the recommendation from Holmes Hobbies for the TRX-4.

https://holmeshobbies.com/motor-recommendations

TRAXXAS TRX-4
General Trail use:
27t – 21t TrailMaster Sport 550
27t – 21t TorqueMaster 550
12t – 10t CrawlMaster 550
Puller Pro BL 540 Standard
TrailMaster Pro BL 540

I personally run the Trailmaster Sport 550 27T with the stock TRX-4 ESC in both my TRX-4s and it is smooth, powerfull and not expensive.


Also got a question. You suggest to get 80mm shocks or to mod the standard ones.

If you want to keep the stock shocks, another good option for lowering the ride height is to insert a spacer around the shock shaft below the piston. Either way, lowering the ride height is one of the best performance mods you can do, and it also helps in the looks department. Win win!

What size does the spacer need to be? Do you mean by spacer a piece of nitro fuel line around the shock shaft under the piston?

[ThatCarGuy]

So, does the Team Raffee body fit on the stock TRX-4 Defender Chassis?

[DirtBug]

Will swapping to slightly softer spring rates f/r effectively give you a lowered ride height without switching to a shorter length shock, which I assume would limit the suspension travel range?

[BashNSlash]

Originally Posted by new2rocks

If you want to keep the stock shocks, another good option for lowering the ride height is to insert a spacer around the shock shaft below the piston.

I'm having a hard time visualizing this - does someone have a photo of how this is done? I'd like to see if lowering the ride height will help with stability on my Defender (without replacing the shocks).