- Gear Diff by Chad Bradley -


Here are some comments about gear differential, those comments are from Chad Bradley, Team Proline Driver.

We ask these questions all the time when we're racing, and have heard them asked at least seven times while at the track... and we're sure that as you're reading this you may be asking "What do I do when...?"

...the track is rutty:
Try changing the center to a lighter setting first (3,000-5,000wt); if the car is changing directions out of a bumpy corner, try making the front lighter (3,000-4000wt).

...the track is loose and smooth:
The best way I've found to increase traction with the diffs is to increase the oil weight in the rear diff slightly -3,000-5,000wt.

...if the track is loose and rutty:
A "square" diff setup here helps -5,000wt front, 5,000wt center and 3,000-5,000wt rear.

...the track is blue groove:
Most of the time I run between 5,000-7,000wt in the front, and 7,000-10,000wt center.

...the track is blue groove and rutty:
I would normally just go lighter in the center, but not too light (5,000wt)

... I want more steering entering the turn:
Lighter front oil (3,000wt) and rear (1,000wt)

...I want more steering exiting:
Thicker front oil -5,000-10,000wt

...I want more acceleration out of a turn:
Thicker center oil - 7,000-10,000

...I want it to go better through a rough section:
Use thinner oil for the center (3,000-4000wt) and thinner oil for the front as well (3,000wt).

...it pulls around too much through ruts:
Usually this happens because the oil in the front and center differentials is too thick; reduce weights.

Starting Point
All this is worth nothing if you don't have a starting point. Chad gave us some starting weights for a variety of conditions that will be good at most tracks. You can apply what we've gone over in the article to fine tune your vehicle:

Starting Point Bumpy Extremely loose
Front 5000 wt 3000 wt 3000 wt
Center 7000 wt 5000 wt 5000 wt
Rear 2000 wt 2000 wt 3000 wt