Locker for GP rearend ?? Anyone?

[john01374]

I've made a ton of mods to my GP over the past couple of months and the one thing It really needs now is a locker. I've got the power. I've got the articulation so the fast stuff is no problem.

When going slow this thing will get stuck on almost anything. Does anyone make a locker for the diffs? I could do the JB weld thing and that may be my only option.

 

[snow walker]

Use play dough. I filled the carrier holding the spider gears with it. Works great and if I break too many axles I can always go back to stock.

 

[john01374]

I've done the playdo locker in the past on Pedes and other trucks. Never seemed to work very long and would end up with free play. Putting gears in the axles of the GP isn't exactly the quickest thing in the world so I don't want to have to do it again in a few weeks.

For the $13 it costs I just ordered a spare Diff assembly and filled it with 2 part epoxy so it will be a permanent locker.

I'll report back in a couple of days after I have some run time on the new setup. Really hopping she' more of a crawler now. Hated getting hung up on small objects.

 

[john01374]

Ok. I got the diff filled with 2 part epoxy last night and let me just say that the grease that replacement diffs ship with is some nasty stuff. Once I had the new diff disassembled it took a good 30 mins to clean all the grease off and no amount of brake clean or carb cleaner would removed it. I ended up scraping it out of the gears tooth by tooth then soaking the whole mess in engine degreaser and hosing it off.

After everything was dry I reassembled the diff leaving the ring gear off. Filled the entire diff with 2 part epoxy and while slowly turning the one out drive to be sure to get the epoxy into all the open areas. I then placed the ring gear in place and screwed it down. I rotates the out drives a few times to be sure everything was assembled correctly and to spread the epoxy around then left it to sit over night.

I'm an early riser so I got up around 5am this morning and checked the diff. Sure enough the epoxy cured and she's locked permanently.

I disassembled the rear axle on the truck and it it really wasn't as annoying as I had expected. Not something I wan t to do again anytime soon but not too bad.

Now for the fun part. Testing. I have railroad tracks that run along side of our house and this is a great place to test. I'll tell you that stock with an unlocked diff the GP would get stuck almost instantly if I tried to crawl or stopped the truck for any reason. If I wanted to run there I had to keep the the speed up or I was going to get it.

I pulled onto the rocks and stopped. Getting going again way not problem as the truck would actually climb up and over objects instead of getting stuck and spinning tires. I actually climbed over the rails a couple of times. Yes the chassis scraped but the truck kept moving. I did this for about 15 mins and only got stuck once on loose rocks where the front almost completely off the ground.

On to the dirt hills. The construction company around the corner form me has huge piles of dirt they use for landscaping. We've had some good rain storms last week so the dirt is pretty hard and packed. Stock the truck would make it up about 1/4 of the way before the front end would unload and the rear would dig one hole in the dirt. Locked the truck has no problems making it 1/2 to 3/4 of the way up from a crawl but if the truck looses momentum it's tough to get the truck moving again. keep in mind this is from a crawl and the front diff is still open. Finding the proper line I can make it to the top but it takes some doing.

Last test I did was a simple run around on the driveway. Stock the truck the would roll over when the rear end unloaded. The out side rear tire would grab and the truck would roll. With power going to both rear wheels the truck spins that outside tire and truck doesn't roll over. Cornering is also much tighter at a steady speed but obviously on power the truck has a little more push but not bad. The S-600 also has enough power to spin the truck around at anytime so that is a huge help as well.

Over all I think this was a good mod. I'm going to keep an eye on the shafts but i think they should be ok. If anything breaks I'll report back. Otherwise I think this is our only option for a locker for these trucks at this time.

 

[JBandit03]

I ran a locked rear for a while (locked with simple hot glue gun), and loved it. The only thing is while using rear-steer there is a good bit of binding, and thats where my axleshaft snapping came. Also on a hard take-off(mostly on pavement, but still noticable in grass), the truck will twist to the side like you're turning. I bought an extra diff and use the open one for speed runs and on pavement since I've gotten pretty quick at changine axles out.

As far as changing broken axleshafts, you can make the inner part of the axlehousing a little bigger for the ends of the dogbones so they just slide in and out once you pull the knuckle.