Dodge D150 1990 Service Manual page 753

16 - 14 DRIVE SHAFTS AND UNIVERSAL JOINTS
. A
J9016-27
Fig. 10 Drive Shaft
BEARING
CAP
MAGNET
7663
(J23498A)
J8916-23
Fig. 11 Transmission/Transfer Case Output Shaft
Angle Measurement
T h e i n c l i n o m e t e r f r a m e a n d d e g r e e scale m u s t
face t h e s a m e d i r e c t i o n (i.e., e i t h e r v e h i c l e - l e f t o r
v e h i c l e - r i g h t ) f o r b o t h m e a s u r e m e n t s .
(12) T h e difference between the t w o angles i s t h e
drive shaft f r o n t angle " A " (Fig. 10).
(13) Compare t h e drive shaft rear angle " B " a n d
the f r o n t angle " A " (Fig. 10). The difference between
the t w o angles is the drive shaft v e r t i c a l angle (i.e.,
angle " A " m i n u s angle "B").
Front & Rear Angles
(14) T h e drive shaft v e r t i c a l angle should be a
m a x i m u m o f plus or m i n u s one degree (±1°); other-
wise, t h e drive shaft is v e r t i c a l l y misaligned. I f nec-
essary, adjustment of t h e axle d r i v e p i n i o n gear shaft
vertical angle w i l l n o r m a l l y correct t h e m i s a l i g n -
ment. T h e adjustment i s accomplished b y i n s t a l l i n g
tapered shims between t h e rear springs and the axle
spring pads.
(15) I f t h e drive shaft v e r t i c a l angle is correct, t h e
axle drive p i n i o n gear shaft angle should also be cor-
rect.
(16) A n incorrect drive shaft v e r t i c a l angle is gen-
erally caused by rear axle d r i v e p i n i o n gear shaft
yoke mis-alignment. I f t h e d r i v e p i n i o n gear shaft
yoke is mis-aligned, inspect for loose spring-to-axle
U-bolts, w h i c h w o u l d allow t h e axle tubes to rotate
on t h e springs. Also, inspect for b r o k e n springs, a n d
w o r n s p r i n g shackles, brackets a n d bushings. Repair
or replace as necessary t o correct t h e mis-alignment.
VERTICAL OPERATING ANGLES (TWO-PIECE
DRIVE SHAFT)
A l l o f the drive shaft U-joints m u s t operate a t t h e
correct angle to prolong t h e life o f t h e bearings. T h e
U-joint operating angles w i l l differ according t o t h e
half-shaft length. Also, t h e f r o n t half-shaft m u s t be
p a r a l l e l to the rear axle d r i v e p i n i o n gear shaft.
The front half-shaft and t h e rear half-shaft m u s t be
offset b y a m i n i m u m o f 1/2 of-a-degree from t h e
transmission/transfer case o u t p u t shaft a n d f r o m
each other.
The center U-joint operating angle can be adjusted
by replacing t h e center b e a r i n g support. A d j u s t i n g
the rear U-joint operating angle is accomplished b y