Hyundai HL955 Manual page 142

Problem
Excessive transmission
noise (Under load or no
load)
Foaming oil
Oil ejected from dipstick
Machine vibrates
Machine lacks power and
acceleration
Torque conver ter stall
RPM too high
Cause
Too low engine low idle.
Wo r n p a r t s o r d a m a g e d i n
transmission.
Warped drive line between engine
and torque converter.
Low or no lube.
Incorrect type of oil.
High oil level.
Low oil level.
Air leak on suction side of pump.
Plugged breather.
Aerated oil.
Low engine speed.
Fa i l e d u n i ve r s a l j o i n t s o n
transmission dr ive shaft or
differential drive shafts.
Engine high idle speed set too
low.
Incorrect transmission oil.
Aerated oil.
Low transmission pressure.
Warped transmission clutch.
Torn transmission control valve
gasket.
Brake drag.
Failed torque converter.
Low engine power.
Aerated oil.
Stuck open converter relief valve.
Leakage in torque converter seal.
Torque converter not
transferring power (Bent fins,
broken starter).
3-86
Remedy
Check engine low idle speed.
Remove transmission suction screen. Inspect
for metal particles.
Repair as necessary.
Inspect drive line.
Do converter-out and lube pressure test. Do
transmission pump flow test.
Change oil.
Transmission overfilled or hydraulic pump seal
leaking.
Add oil.
Check oil pickup tube on side of transmission.
Inspect breather on top of transmission.
Replace.
Add oil.
Check engine speed.
Check universal joints.
Check high idle adjustment.
Change oil.
Add oil.
Do transmission system pressure test.
Do transmission clutch drag checks.
Inspect gasket.
Do brake drag check.
Do torque converter stall speed test.
Do engine power test.
Put clear hose on thermal bypass outlet port.
Run machine to check for bubbles in oil.
Do converter-out pressure test.
Do converter-out pressure test.
Replace torque converter.