Sigh...Need Help Again =\

[RevoRoughin]

Ok, I've recently replaced all of my A-arms, the front Diff, and the front bulkhead (was hard as heck to put back on...im guessing because of me having to "make" screw threads in the new bulkhead) anyways, first issue was grinding from the car, now after replacing all that I still get it, I have yet to check my rear diff which im doing as I type this, however, any other ideas what it could be? it sounds like its coming from the front to me...here is a short vid.

http://www.youtube.com/watch?v=KUlgsULg00U&feature=channel_video_title


Thanks

~ RevoRoughin

[RC-Fan]

if you replaced the front, and still doing it must be the rear, also check that it is not the spur.

[RevoRoughin]

The spur is meshing perfectly with the motor...Could it be the gear box connected to the Spur..?

[hurley747]

The spur is meshing perfectly with the motor...Could it be the gear box connected to the Spur..?

Possibly ... Did you properly grease the diff gears?

Make sure your chassis/ gear boxes and diff are all empty of loose gravel, dust, or gear teeth

Just check you spur and pinion mesh again and do the paper trick becuase it sounds like that to me but im not sure...

[RevoRoughin]

whats the paper trick?

[mgbrandy]

I bet it's your rear diff. Mines went out 5 times in four months

[Dadx2mj]

It is really hard to tell if the noise is coming from the front or the rear. I f it is making the noise on acceleration I tend to look at the rear first, if it is making the noise on braking I look at the front first. Reason being when you accelerate the weight shifts reward putting more stress on rear diff and when braking the weight shifts forward putting more train on front diff.

[RevoRoughin]

True, I placed the diff i "thought" was broken from the front in the rear and turned the drive shaft, it all seemed to link up...guess i just have to buy ANOTHER diff and throw it in the rear...if that doesnt change it then idk what the issue is because ill have two brand new diffs.

[BREADY62]

it sounds like the gears to me

[Dadx2mj]

True, I placed the diff i "thought" was broken from the front in the rear and turned the drive shaft, it all seemed to link up...guess i just have to buy ANOTHER diff and throw it in the rear...if that doesnt change it then idk what the issue is because ill have two brand new diffs.

Could just be that the diff needs to be shimmed or that you have a bad bearing some where around the diff or on center shaft. I have fought diff noise on a few occasions but in the end my truck still is using the original diff gears. I did have to replace a diff cover once and a couple of bearings but the diff itself (ring and pinion) are tougher than they are given credit for IMO.

[cz6418]

The paper trick:

Take off the cover that is over the spur and pinion gears. Loosen the screw that holds the motor to the motor mount, so it can slide freely. Cut a thin strip of normal notebook paper, and place it between the spur and pinion gears. Push the motor and spur gear (not too hard) against the pinion gear, then tighten the motor screw. Roll the truck (forwards or backwards? whatever works) so the paper comes up out from between the gears. A new strip of paper should fit between the spur and pinion gears, without binding or crumpling. I have tried it already a few times and it has worked great every time.

[cz6418]

sorry i got the pinion and spur gears mixed up....

[genXrated]

Didn't they just say something about not using the paper trick anymore in RC Car Action not too long ago? And that you were supposed to instead push the gears tight together and back them off a hair until you just start to feel the teeth 'click' together?

I'd think it's your rear diff also, unless you have some junk bearings. Did you check them also?

[E-RevoVXL]

One of the bearings in the bulkhead may have broken, making the diff gears not click correctly, which makes them sound stripped.

[RevoRoughin]

Just replaced the rear diff, all the bearings everything with a traxxas kit, question, I didn't have traxxas "differential lube" so I tried grease, didn't turn right... So I filled it with 50k shock oil....is that ok? It seems to spin alright...also steering servo started messing up...so I bought the gears to replace them, anything special about doing that?

[RC-Fan]

what do you mean with the grease on the diff didn't turn out right? I've put grease on mines without issue, did the grinding noise go away?

[RevoRoughin]

I've yet to run it, replacing the steering servo gears first, and I mean on the inside of the diff, where the three small gears are, it seemed to bind, and I doubt it's the gears considering I just opened the pack, so I filled the diff with 50k shock oil and it seems to spin better but still a little binding.

[RC-Fan]

I've yet to run it, replacing the steering servo gears first, and I mean on the inside of the diff, where the three small gears are, it seemed to bind, and I doubt it's the gears considering I just opened the pack, so I filled the diff with 50k shock oil and it seems to spin better but still a little binding.

it shouldn't be any binding, open it again and set it properly also do not overtighteen the screws, they should be flush on the other side, spin the diff manually before installing, it should run smooth, also install the diff on the same position on the bulkhead or it will spin backwards.

[Dadx2mj]

So I filled it with 50k shock oil

Never heard of 50k (50,000} shock oil. That is diff fluid weight and would work fine. Shock oil would be 50 weight and that would be too thin to give proper diff action IMO.

[RevoRoughin]

Okay, I'll be taking apart the diff to ensure it's out together properly, when I removed the old
screws there was some kind of oil, will the 50k shock oil suffice? My local hobby hop doesn't have any diff fluid
Edit: I swear it says 50k shock dad, I'll check when I return to my barracks room...man I need a nicer hobby shop around here.

[RC-Fan]

Okay, I'll be taking apart the diff to ensure it's out together properly, when I removed the oil screws there was some kind of oil, will the 50k shock oil suffice? My local hobby hop doesn't have any diff fluid

are you taking about 50k or 50wt? 50wt is shock oil, 50k is 50.000 diff lube, don't know how shock oil will work I prefer grease,

[RevoRoughin]

You used grease like the kind you put between the bulkhead and the diff? Sorry for the confusion, just looks like oil in the old diff I'll try grease again when I get hOme

[BigDaddy01629]

, also steering servo started messing up...so I bought the gears to replace them, anything special about doing that?


What is the steering servo doing. Is it jst making a grinding kind of noise, and also the servo horn keeps moving very little (like its shaking) and does not stay on at a place. If that's the case there is nothing wrong with the steering servo. They are digital servo's and are suppose to do that.

[RevoRoughin]

It would turn to te right, but not the left, then it stopped all together, gonna replace gears after class.

[RC-Fan]

You used grease like the kind you put between the bulkhead and the diff? Sorry for the confusion, just looks like oil in the old diff I'll try grease again when I get hOme

I use automotive grease from the hardware store, yeap the same that you put to lube the gears.

[RevoRoughin]

I use automotive grease from the hardware store, yeap the same that you put to lube the gears.

okay thanks alot man ^.^ im using "molybdenum grease" from tamiya, its what the local hobby shop gave me, hopefully that does the trick :D...need my baby running again.

[hurley747]

The paper trick....

Thanks haha didnt check this thread soon enough