Xray T4 2018 Instruction Manual - page 7
7
964031
S 3.5x10x0.2
1. GEAR DIFFERENTIAL & FRONT SOLID AXLE
1. GEAR DIFFERENTIAL & FRONT SOLID AXLE
971240
O 24x0.7
After disassembling the gear diff the large O-ring may have an increased size and
may be more difficult to re-install. We recommend either inserting the old O-ring
carefully in the diff cover, or replacing the old O-ring with a new O-ring if the old
one cannot be made to fit properly.
Fill differential up to the top of the diff pin.
DO NOT fill the diff to the top of the housing.
TO ENSURE YOU HAVE THE SAME AMOUNT OF OIL FROM REBUILD TO REBUILD, DO THE FOLLOWING:
NOTE
SOFTER oil increases rear traction, HARDER oil increases on-power steering and
stability. It is important not to use soft oils in high-traction conditions as this would
not increase traction, but would make the car loose as the car would become too
twitchy.
However, if the oil is too soft, it could generate the same effect like the car has no
traction. Therefore it is very important to choose the correct oil very carefully. We
recommend using softer oil first, then try harder oil to better understand the effect
on the car’s behavior at the track. Choose the oil accordingly.
TIPS FOR FRONT DIFFERENTIAL
To increase on-power steering and cornering speed, the gear diff can also be used in the front.
NOTE: If you use the gear diff in the front, we recommend using optional #304971 HUDY
Spring Steel™ outdrives because the stress on the outdrives in the front is much higher
than in the rear.
USE THESE OILS FOR FRONT DIFFERENTIAL
500,000 cSt (HUDY #106650)
1,000,000 cSt (HUDY #106692)
2,000,000 cSt (HUDY #106694)
To make the front differential tighter, you can use cleaning gum instead of oil.
IMPORTANT!
Using cleaning gum instead of oil in the gear differential can lead to gear breakage because
the gears are working under dry conditions.
LOW TRACTION
1000cSt
(HUDY #106410)
2000cSt
(HUDY #106420)
TIPS FOR DIFFERENTIALS
7.90g
9.40g
#107865
HUDY Ultimate Digital Pocket
Scale 300g±0.01g
INITIAL SETTING
3000cSt
MEDIUM TRACTION
2000cSt
(HUDY #106420)
3000cSt
(HUDY #106430)
4000cSt
(HUDY #106440)
5000cSt
(HUDY #106450)
HIGH TRACTION
5000cSt
(HUDY #106450)
6000cSt
(HUDY #106460)
7000cSt
(HUDY #106470)
8000cSt
(HUDY #106480)
9000cSt
(HUDY #106490)
10000cSt
(HUDY #106510)
SUPER-HIGH TRACTION
10000cSt
(HUDY #106510)
15000cSt
(HUDY #106515)
20000cSt
(HUDY #106520)
➊
Put the diff (without oil) on the scale and check the
weight (approximately 7.90g)
➋
Slowly pour oil into the diff and watch the weight. Add 1.5g of oil
into the diff. The approximate weight of the diff including oil is 9.40g.
7.9g + 1.5g = 9.4g
#304932
GRAPHITE GEAR DIFF BEVEL &
SATELLITE GEARS (2+4)