XXX-NT diff.........GRRRR!

[m1marty]

I've had this truck for two weeks now. I bought some Pro-Line monster mashers for playing around in the yard....diff let go in about 3/4 tank. Ok, no big deal- I rebuilt the diff and figured maybe I had the slipper a little tight (pulled wheelies and hooked up really well) I put the mashers back on today and same damn thing. The diff gear stripped. I had the slipper fairly loose and it still happened. Mill is stock save for a drake pipe and motor savers filter. The truck is tuned well. Is this going to be a constant problem with this thing if I use any tires that grip? Any *bullet-proof* parts? I rebuilt the t-maxx tranny 3 times before I did a FOC conversion. I drive moderately (easy roll ons with the power, no pinning the gas in turns etc) Really kinda discouraged right now. Any advice?

 

[olds97_lss]

Get this: RRP Monster Diff Gear (aluminum)
These: Losi Carbide Diff balls
And a new set of these: Monster Diff Washers

There was also a cnc'd aluminum diff nut that replaced the mini-locknut and the plastic thing it goes into, but I can't find it at any normal sites anymore. I can only find it at the MFR's site and it's not easy to post a link for it.

Go here: http://1hg.com/home/Indexnf.htm
Hover over the "Precision Catalog" bar, click on components, choose Losi Triple XNT and it will be the only part listed, part number 1800.0. When I bought mine, I just found it at my LHS (pure luck that they had it). Horizon hobbies used to carry it, but the don't any longer.

Anyway, with the RRP gear, carbide diff balls, new rings and if you can find the nut, it will make a very durable long lasting diff. I had the above setup (also used Niftec diff grease) fresh boca green seal bearings throughout and ran about 6 gallons through the truck without failure. Then I sold the truck.

 

[m1marty]

Olds,
Thanks for the reply bud. I snagged a aluminum diff gear last night and had the LHS guy watch as I rebuilt it *again*. I also replaced the idler gear. Truck worked well for 1 tank of gas, but I now have the *gritty* feeling back in there. Next will be the carbide diff balls and new washers. Kinda frustrating, as this truck only has 1/2 gallon of 20% thru it, and it is not driven hard. Maybe I got luck of the draw, but between this and the T-Maxx, fixing something after every tank is getting old. I fully expect routine maint. and fixing *oops* mistakes, but I think this is a little much.:surrender

 

[olds97_lss]

Once you replace the diff balls and rings with the carbide, it will feel as smooth as silk. The stock diff balls are soft and get out of round in a hurry, which in turn destroys the rings.

Your on the right track though. Throwing a bit of money into the diff makes it a much more stable device that can take some abuse. I literally didn't have to mess with the diff for 5 gallons or so other than to change bearings. I'm just a basher, so messing with the diff action wasn't a primary concern.

Just don't forget to grease the balls or they will overheat and ruin the gear and rings.

Also, after running it a bit, you need to tighten the diff up as it wears in. Otherwise it will slip and chew itself apart. They aren't designed to slip like in the 80's.

 

[m1marty]

I'll get there I'm sure......just trying to explain the need for more parts to the wife.:LoL: I've already passed the price of the truck by a few bucks, but I got the truck pretty cheap. I have a "Draked" .12 on the way and I want to make sure the diff is sorted before I put roughly twice the hp to it. Thanks again for the help!