im new to rock crawling but not to rc. im interested in designing and making my own pulling tractor for pulling a trailer no comps tho. i was wondering is their a strong diff that can be locked easily and unlocked easily using a servo or just push a button or something simple as in not having to pull out the diff, screwdriver etc ye alll know any way.
thanks

I think the Tamiya Hilift has diffs that you can lock and unlock without much fuss. But I'm not sure if that will be strong enough for your application or not. When you say "pulling tractor" I think of these things that pull a weight sled:

http://www.nrctpa.org/photo_gallery/...e/IMG_4782.JPG

The hi lift does have a way of locking and unlocking the diff but it requires the axle case to be opened up to insert/remove a pin. For the most part if you're building a pulling tractor (like what was posted above) you'll want a solid axle without any type of differential.

ya thats the kind of tractor. id say ill end up with no diff. when im turning will it struggle burn rubber or what will happen??? i plan on cutting the inserts like i say done in a sticky on these fourms.
thanks guys

I think you're thinking of two different things. People star cut the foams on rock crawlers to get maximum tire flex. I don't believe they do that in tractor pulling.

As for the diff, without one it'll just make the turning radius a little wider.

Yes, it will "struggle" and not turn as tight with a locked diff. When are you ever going to be turning? And when you are do you need to turn tight?