There are different part numbers for the standard and lightened and then I believe there is also a coupled rear top shaft as well, so I think 3 part numbers for the rear top shaft 2 for the front.

Only one of them is lightened:

91016 = Standard Rear Top Shaft
91131 = Factory Team Lightened Rear Top Shaft
91180 = Rear Top Shaft for coupled slipper (91188)

Bent

thanks, will just pick up the lightened one, give it a tear down and see if there is any other damage.

Yes. Those parts are all worn out. There is so much lash (from wear) in the drive bone that the pin gets hammered and eventually fails.

Maybe the stub axle is salvageable, but if it were me, I wouldn't even try.

Did you run them dry (without lubrication)?

You want the one with the 80 in the part number.

I'd never run the lightened one in this truck.

I've been running the lightweight front and rear ones since last August. Running V1 and V2 Center diff, and the VTS

No problems. Just fyi

Why not ?!?

If you're not going to run the coupled slipper hub why wouldn't you want the lighter option top shaft ?!?

I'v been running it in mine front and rear for more than a year now on high bite indoor clay and outdoor astro turf........not a single issue so far :sneaky:

Just recently replaced it with a new one during a total rebuild......not necessary at all as it showed no signs of wear or tweak.......but felt obligated to since I had been running it for over a year ;)

Bent

Traction Rolling Bad
 

While racing last night, I was traction rolling real bad getting into the corners. My track is high bite wet clay. I'm running ProLine Suburbs MC compound on JConcepts Hazard wheels. I"m running the 8MM mod in the rear. I have 2.0 sway bars front and rear. 27.5wt blue front springs in the front / 32.5wt blue front springs in the rear. RCShox V2 center diff with 8 pins. 25MM ride height all around.

Any suggestions guys? Remove the 8MM Mod for indoor high bite track? Change springs?

I didn't have these issue at all while outdoors with truck setup the same way.

If you don't plan on ever running the coupled slipper hub, I guess it's okay...but I can't see how having this particular part be lightened makes the truck perform better or be more durable ( in a really meaningful way compared to the effort it takes to change it).

IMO.

Lower the ride height.

This is true.

What's your camber set at? For that type of track I would try the yellow springs in the front. and for the rear put White front springs.

I haven't tried the the 8mm mod yet. I would suggest 6 pins in the Center Diff.

go to 23-24 mm ride height and increase camber to like 1.5 all around.

Now that I'm home, I checked camber and found that I'm at -1.5 all the way around. Also, ride height is about 23 in the front and 25 in the back. So I will lower the back. Blue Sway bars front and back.

Should I also try a smaller sway bar?

Positive 1.5?