How to: Build a great diff...

[Dudders]

Hi All,

Seems like this is a real dark art!, darker than speedo settings!!!

So, how do you get a lovely smoooooooth diff? When I build mine it's either lovely and smooth, but slips, or it feels like its built with crunchy nut cornflakes.

Do you sand your discs and replace balls every time?, is it the balls?

Fanx!

[RudeTony]

Its all about balls Neil and my balls are the nuts - LOL
Get on the RudeBits site for your associated balls dude

[mattybucks]

I always follow The guide on Trf racing.

[Chequered Flag Racing]

Originally Posted by mattybucks

I always follow The guide on Trf racing.

hope there's something flat under those diff rings and not just the rubber matting

[DavidAMS]

i had the same question so i studied the dark art and now i can build very smooth diffs.

Firstly i watched these videos

http://www.youtube.com/watch?v=IIYPo...eature=related

(He mentions it once briefly but you need to tighten your slipper clutch when you breaking in the diff)

The slipper clutch needs to slip before the diff.

The problem with the above method is the way he sets the diffs before first drive, i found the diffs to still slip. this way that Rich D mentions is the best, this will ensure there is zero slip before you go for a drive.



''To set the diffs, this is my method.......

Car facing away from you, hold left rear wheel with left hand. Hold spur gear with left thumb. Turn right rear wheel forward slowly at first still holding the left rear wheel and jamming the spur. You should see the slipper plates turning. If they arent then either your diff is too slack or your slipper is set too tight.
Its a balance that you`ll get a feel for. When its set right, then the diff action should be smooth but it shouldnt slip when you test it on the bench.

For the front, just face the car nose towards you and repeat the method above. I try turning the right wheel slowly at first until im happy that it`s not slipping. Once its somewhere near, i turn it more quickly, kind of "jerk" - this is more like the motor would turn the transmission. If you hear it slip, just tighten it 1/8 of a turn further.''





The slipper clutch setting is just as important as the diff setting. If the slipper is too tight then the diff will slip no matter.

for 2wd just hold the back wheels and try rotate the spur, if the slipper nut moves then its too loose, if its unable to be turned then its too tight, you want to be able to turn the spur without the slipper nut moving.

whenever i rebuild a diff now i always rebuild my slipper aswell.

hope that helps

[ianjoyner]

Anyone else find their diff can feel fine before a run, crunchy after a run, then fine after it's sat for a while?

It's as though the heat affects the grease or perhaps the size of the components.

[Appie53]

I'am not an expert, but for the diff I allways used, and will use teflongrease!!
It's still the best, for me