Diff Binding

[Butters]

Hey all,

Yesterday I began antoher tear down and rebuild of the truck for this weekends upcoming race. Refilled my diffs and reassembled the front bulkhead. I didn’t have any shock on yet and noticed when I rotated the drive cup when the suspension is in a fully compressed situation the pinion and the diff gear bind up. I am looking to see if anyone else has noticed this problem. This only happens when the truck compresses to the point where the skid plate could make contact with the ground. I know some off you might state stiffen up the suspension but that is not a choice in this case for racing. I am looking to see if anyone else has come across this problem. I never noticed it before till I was doing some testing.

 

[Blazer X]

Make sure you don't have too long of a screw in that position causing it to bind up.

 

[Butters]

Blazer which screws are you talking about?

 

[Blazer X]

the screws that come up through the skid plates just below the diff cups, if they are the long ones they will bind

 

[DOOBEEWHA]

Yep... same thing happened to me when I upgraded the screws and bolts on the truck. Had to pull the srcrew and shorten it abit ... Problem solved.

 

[Butters]

Yes if the skid plate screws are longer than normal the diff should bind all the time (Free state or compressed. The only binding I'm getting is when the suspension (skid plate) bottoms out. The truck roll beatifully when it's at ride normal ride height (Bones level). Thats why I'm confused on whats binding. I will pull out the skid plate screws later today and see if that could be the problem.

 

[DOOBEEWHA]

Think one of yiour diff cups is pushing inward towards the diff.
Can you hear where the lock up is?
Maybe a worn out diff housing. Don't know for sure.

 

[Jeremy]

did your bearings look good (the ones where the pinion sit on )

 

[stevage]

I'm having the same problem except it does it only when i apply full brakes.I did check the diff out but i could not find any worn gears.

 

[Jeremy]

I would say your pinion gear and your ring gear mesh is not correct .. (might have some movement ) .... shim the pinion gear so there is barley any movement. make sure that the pinion is not to far toward the diff cup/ or too far back for that matter ... Make sure your bearings are good all around get rid of any slop within the diff

 

[stevage]

What happened that it got like that.

 

[Jeremy]

nothing really they come stock with way too much slop

 

[stevage]

I'm a newbie at shiming so could anyone give some advice,would it also be a good idea to do the back diffs as well.I might sound a little dense asking about that,but i have no clue.

 

[stevage]

I got the shimming part taken care of.I found the article on here about it.