Road Test - Pontiac tempest 1968 Service Manual

7E-60
1968 P O N T I A C SERVICE M A N U A L
MANUAL LINKAGE
Manual linkage adjustment and the associated neu­
t r a l safety switch are Important from a safety
standpoint. The neutral safety switch should be
adjusted so that the engine w i l l start in the Park
and Neutral positions only.
With the selector lever in the Park position, the
parking pawl should freely engage and prevent the
vehicle from r o l l i n g . The pointer on the indicator
quadrant should line up properly with the range
indicators i n a l l ranges.
ROAD
TEST
(ATTACH PRESSURE GAUGE TO TRANSMISSION)
The car owner should accompany the tester and
the complaint analyzed under the same or simulated
conditions.
SHIFT PATTERN CHECK
Check a l l the shifts i n the following manner:
Drive Range:
Position selector lever i n Drive Range, accelerat­
ing the vehicle from 0 mph. A 1-2 and 2-3 shift
should occur at all throttle openings. The shift
points w i l l vary with the throttle opening. As the
vehicle decreases in speed to 0 mph, the 3-2 and
2-1 shifts should occur.
Super Range:
Position the selector lever i n Super Range and
accelerate the vehicle from 0 mph. A 1-2 shift
should occur at a l l throttle openings. No 2-3 shift
can be obtained in this range. The 1-2 shift point
w i l l vary with throttle opening. As the vehicle de­
creases i n speed to 0 mph, a 2-1 shift should occur.
Lo Range:
Position the selector lever in Lo Range. No up­
shift should occur i n this range, regardless of
throttle opening.
2nd Gear Overrun Braking:
Position the selector lever i n the Drive Range and,
with the car speed at approximately 35 mph, move
the selector lever to Super Range. The transmission
should downshift to 2nd. An increase in engine rpm
and an engine braking effect should be noticed. Line
pressure should change from 60 psi to approximately
150 psi i n 2nd.
1st Gear - Downhill or Overrun Braking:
With the selector lever in Super at approximately
30 mph at constant throttle, reposition the selector
lever into Lo Range. An increase in engine rpm and
a braking effect should be noticed. Line pressure
should be approximately 150 psi (Figs. 171 and 172).
TURBO HYDRA-MATIC TRANSMISSION-OIL PRESSURE CHECK
I. O i l Pressure Check - Road or Normal Operating Conditions
While road testing with the transmission o i l pressure gauge attached and the vacuum
modulator tube connected, the transmission pressures should check approximately as
shown in F i g . 7E-171.
Super Range
Minimum Maximum
2nd Gear - Steady road load at approximately
25 mph 145 psi 155 psi
Gear
Selector Lever Position Minimum Maximum
1st Drive \
2nd
( " Z e r o " throttle to full I 60
150
3rd throttle) j
3rd
Drive Range, Zero Throttle 60
at 30 mph
Reverse Rev. (Zero to full throttle) 95 260
F i g . 7E-171 O i l Pressure Check - Road or Normal Operating Conditions
I I . O i l Pressure Check - With Car Stationary and Engine at 1200 rpm
With the transmission o i l pressure gauge attached and the vacuum modulator tube
disconnected, the transmission pressures should check approximately as shown in
F i g . 7E-172.