deanR

hey
last weekend me and my cousin with his brand new 4.6 rtr went out to the dunes to drive our savages. mine is just a 4.1, but not for long. any way after about an hour of driving, all of the teeth in my diff had stripped. One even broke in half. So we took it to the car and i had extras, so i fixed it (i love easy access diffs!). so i started it back up again, and literally 5 mins of driving and the same thing happens. i never stripped those before. but, when i rebuilt it, i didnt put any grease in. but i have ran it before without grease. has anyone else had this problem??
thanks a lot,
dean

oh and it was the back one

racer man05

sounds like that easy access diff is flexing and messing up the gear mesh. that would be my guess as i have never had that heppen to me.

-SomeGuy-

How do the bearings look? If one is blown then the diff is out of alignment and would cause this kind of problem. There are 4 bearings you need to look at, the two on the drive cups that go to the wheels and the two that are holding the 13t gear in place. Only other thing i could think of is maybe the plastic diff cup is flexing but with a 4.1 i highly doubt it but you never know. Since you plan on getting a bigger engine sooner or later you might look into the alloy diff cups asap.

deanR

no i forgot to mention its the four inside gears.

-SomeGuy-

That changes everything. Hmmm, so far i have had zero problems with those except when i still had the 2 gear setup and i threw in my first picco, i love doing donuts so they didnt last long.

When you fixed it did you replace the cup as well? If not then it might be eaten up inside and the gears are not aligned properly. Get yourself some XSS diffs and call it a day, they are shimmed and everything, like i said before you will need them sooner or later.

deanR

thanks a lot man. i have had trouble with the ring gear and the other small one. but i shimmed those a whiiile ago and i havent had trouble since. its the first time that happened.
so tomorrow im going to see if i can pick up an assembled diff. i hope that will solve my problems
oh and on that same outing my rotostarter fried. im thinking about getting a pull starter. are they worth it?
thanks again
dean

-SomeGuy-

I've tried both and I prefer the ease of the roto, even if it means having to carry it around with me.

Bubba_1976

The main reason I bought a savvy is because i was getting sick of pull starts lol

deanR

hmmm well i think im gonna try out the pull start. if i dont like it i can always switch back, and fix the switch on my roto start
thanks for all the info, i really appreciate it

-SomeGuy-

Let us know whats the verdict on your diff.

deanR

alright will do
thanks again

deanR

my back diff cup is so messed up, it obviously worn out enough for them to strip. thanks for the help, i got new ones

twomanytoys

You have to at least have grease in the diff. The heat build up in the diff gets pretty hot so with no lube Im sure it was smokin hot. Dont run without grease.

Oregon mud

Broken gears in the front are from the brakes being to hard and the rear ones going out is from landing jumps on throttle. Usualy. There are always exceptions (sp*) to the rules. And grease is a must inside the diff case.

deanR

i am pretty sure thats what did it. it in second gear going probably at least 30 mph and i went off a dune. i accidentaly stayed on the gas and it landed on the back really hard