OFNA worn out diff cases...Please help!!!
 

Hi rctech!! I already posted this in the OFNA GTP2E thread but I figured it would get more attention here.

I am having a major problem with constantly wearing out diff cases where the pinion goes through. The diff cups eventually start getting wobbly and come out of the diff. I bash my GTP2E every day and usually do speed runs on the weekends so it gets a lot of hard usage. Do I need to shim the diff pinion tighter to the bevel gear on my diff? I usually have to replace the diff case about every 2 wks! Please help!!

When's the last time you replaced your center ds? Looks like they have been worn down a good bit which will lead to quicker wear on the diff cups.

Second item is, what are you running battery/motor wise? High power + speed runs and heavy jars on the drivetrain will lead to more wear.

Don't look at the cuff only. Look towards the drive shaft. The pin is harder the cuff or shaft could be bent. Just by photos shown the cuff looks like in move 8-10mm's. Cheaper way use RC fuel hose to take up play b/n endplay of cuff and driveshaft.

Good luck!! it a hobby!!

I usually replace the center driveshafts every 2 to 4 wks.

My setup is mamba monster 2200kv combo and gearing is 38/27 for weekday bashing and 38/34 for speed runs. The car sees 110+ mph regularly on the weekends.

The pics are of the rear diff Which does not have much play. Probably only about 3 or 4mm. The front shaft has a lot more play but i have relieved the play with a piece of a cork plug which minimizes the play.

Is the issue in the front or rear diff? What gear oil are you using?

Make sure that drive cup is not touching the diff case and replace the with a fresh bearing.

It happens mostly in the front but I think i mite have solved the issue which was a bent pinion shaft. Just installed a brand new one and hopefully everything will be fine.

For gear grease I usually used Mobil1 synthetic grease or black grease.

I am also having a pretty common occurance with the inner bearings that are right next to the pinion. I have had at least 3 of them just get destroyed somehow and leaving little balls and pieces all inside the diff case causing wobble In the drive cup.