Ok guys I recently got a slash 4wd and I used A vacuum cap for a 1to1 car all I had to do was sand the outside of the cap some and cut off the end. The size of the cap is 7.9 mm it came in a variety pack from Harbour Freight. Ill try to get some photos this weekend.

It's not the scrapes that concern me. Stuff gets wedged in there and starts grooving the shaft. One of my shafts got such a groove in it that it twisted under load and had to be replaced.

I heard those aren't all that great because rocks and stuff can get in behind the servo guard and actually cause damage to the arms. This is one of the first things I looked in the buying for my truck because I didn't like the way the servo arm was exposed like it was, but after hearing the complaints after asking about them, I changed my mind. Are they as bad as people say?

I did just order the Tekno center drive shaft and saw on the Traxxas forum someone who used heatshrink along the whole shaft, which is what I may do. I did remove the clear plastic cover as well, debris gets in there but it falls out easy as well.

I used a small piece cut from a foam sheet that I stole from my wife and daughters craft closet. Think it was a dollar or two at Hobby Lobby.

You're welcome. Square hole was easier and there was no friction against the shaft.

Thanks for sharing. Btw, are those scratches on your driveshaft due to the steering mechanism?

Not sure. I bought it used and it was already like that. I have been watching to see why but no luck yet. I have an extra brand new drive shaft but I want to narrow down the cause prior to installing it. I think the previous owner may have had the servo a bit loose at some point but I completely broke it down to the frame to dye it the day i bought it and had already loosened everything before I noticed the scratches.

Mine did that too - i think it's from the steering arm, when at full throw rubs against the driveshaft.

I've posted this pic before, but this is what happens when "stuff gets wedged in there" and really grooves the shaft.

If your transmitter will allow you to do so, set your steering end point to stop just before rubbing the drive shaft. I can't remember if it's full right or full left steering that does it. Just flip the truck over and steer fully. You will see the rub.