Chevrolet 10 Series 1970, Service Manual

Page: 472 / 671

CLUTCHES AND TRANSMISSIONS 7-42
8. R ein stall tran sm ission support cro ssm em b er to
adapter and fra m e.
9. In stall tran sm ission to tra n s fe r case adapter attach­
ing bolts (torque to 21 to 29 ft. lb s.) and rem ove lift
equipment.
10. Connect fron t and r e a r axle prop shafts to tra n sfer
case.
11. In stall exhaust system c ro s s o v e r pipe.
12. Connect manual con trol le v e r rod and detent cable to
tran sm ission .
OTHER SERVICE
Although certain operations, such as o il pan gasket or
manual le v e r s and o il sea l replacem en t, detent cable,
govern or, f i l l e r pipe
“ O”
rin g, speedom eter d rive gear,
case extension “ O ” rin g and r e a r o il seal, vacuum
modulator, and interm ediate clutch accum ulator c o v e r
s e r v ic e may be p erfo rm e d fro m underneath the veh icle
TURBO HYDRA-MATIC 350
Accu rate diagnosis of tran sm ission problem s begins
with a thorough understanding of norm al tran sm ission
operation. In p articu la r, knowing which units a re in­
vo lved in the variou s speeds o r shifts so that the sp e c ific
units o r circu its in volved in the problem can be isolated
and investigated fu rth er. A n a lytical diagnosis w ill p ro ­
tect the technician fro m com e backs and certa in ly w ill
im p rove owner satisfaction .
An im portant and often overlook ed aspect of diagnosis
is finding out s p e c ific cu stom er com plaints. F o r this
purpose a short rid e with the custom er w ill often p ro ve
b en eficia l. It may be found that the condition the custom­
e r wants c o rre c te d is standard and should not be altered.
F ig „ 5 — Pressure Tap Locations
13. Connect vacuum m odulator line and speedom eter
d rive cable to transm ission.
14. A ssem b le rod on tra n s fe r case shift le v e r b efore
in stallin g rod to tra n s fe r case shift linkage. Torque
shift le v e r attaching bolt to 40-45 ft. lbs.
15. L o w e r v e h icle and rem ove fro m hoist.
16. R e fill tran sm ission through f i l l e r tube follow in g the
recom m ended procedu re outlined in this Section.
17. Check tran sm ission fo r p ro p e r operation and fo r
leakage. Check, and if n ecessa ry, adjust linkage.
OPERATIONS
without rem ovin g the Turbo H yd ra -M a tic 350; th eir
s e r v ic e procedure is covered in the O verhaul Manual and
is not repeated here. R e fe r to the Turbo H yd ra-M atic
350 Section o f the Overhaul Manual fo r a ll other s e rv ic e
operations not covered here.
DIAGNOSIS PROCEDURE
The fo llo w in g sequence, based on fie ld experien ce, p ro ­
vid es the d e s ire d inform ation quickly and in m ost cases
actually c o rre c ts the malfunction without req u irin g the
rem o va l of the transm ission. D etails o f the item s listed
in this sequence are co vered fu rth er in the text.
SEQUENCE FOR TURBO H Y D R A -M A T IC 3 5 0
D IA G N O SIS PROCEDURE
1. Check o il le v e l and condition.
2. Check and c o rre c t detent cable adjustment.
3. Check and c o r r e c t vacuum line and fittin gs.
4. Check and c o r r e c t manual linkage.
OIL LEVEL A N D C O N D IT IO N CHECK
Alw ays check the o il le v e l b efo re road testing. O il
must be v is ib le on dip stick p r io r to operating the v e ­
h icle. E rra tic shifting, pump noise, o r other m alfunc­
tions can in som e cases be tra ced to im p rop er o il le v e l.
O il le v e l should be checked with the s e le c to r le v e r in
the P a rk (P ) position, engine running, and the veh icle on
le v e l pavement.
Fluid le v e l should be to the F U L L m ark with the tran s­
m ission at norm al operating tem peratu re (170°-190°F.).
W ith w arm flu id (room tem p eratu re), the le v e l should be
at o r 1/4 inch below the ADD m ark.
If o il le v e l was low, r e fe r to O il Leaks.
The condition of the o il is often an indication of whether
the tran sm ission should be rem oved fro m the veh icle, o r
to make fu rth er tests. When checking o il le v e l, a burned
sm e ll and d iscoloration indicate burned clutches o r band
and the tran sm ission w ill have to be rem oved.
M A N U A L LINKAGE
Manual linkage adjustment and the associated neutral
safety switch are im portant fro m a safety standpoint.
The neutral safety switch should be adjusted so that the
engine w ill start in the P a rk and Neutral p ositions only.
With the s e le c to r le v e r in the P a rk position, the park­
ing pawl should fr e e ly engage and preven t the veh icle
CHEVROLET TRUCK SERVICE MANUAL