Attention! The main reasons for the abnormal operation of the transmission can be a malfunction of the engine (power loss), incorrect adjustments, failures of the hydraulic transmission system, mechanical drive and processor control system. First of all, you should check the level and condition of the fluid, adjust the traction. If these measures do not lead to a positive result, then you should contact a car service.
Preliminary checks
1. Warm up the transmission after driving.
2. Check fluid level and condition.
3. If the level is below normal, then restore the level and check for leaks (see below).
4. If the level is too high, then drain some of the fluid and check for contamination with coolant that may have entered due to a leak in the radiator.
5. If foaming is found, drain the fluid and replace.
6. Check engine idle speed. Repair and adjust if necessary, as there is no point in checking the transmission further.
7. Check the adjustment and operation of the mechanical transmission drive.
Checking Transmission Condition for Fluid Leaks
1. Liquid leakage is easily established visually and eliminated by replacing seals or gaskets.
2. To detect a subtle leak, park your vehicle after driving a few miles over a blank sheet of cardboard or paper. After about 2 minutes, the leak can be detected.
3. Immediately clean the crankcase and check the condition of the seals in the suspected places.
4. If a leak is not detected in this way, then thoroughly flush the crankcase with a solvent and dry it.
5. Take a trip and carefully inspect the crankcase.
6. If the leak is located, then determine the cause of the leak and how to fix it (for example, replacing the gasket cannot eliminate the leak if the split planes are deformed).
7. Before fixing the leak, analyze the causes of the leak, ensure that the faults described below are eliminated.
Attention! Some types of work to eliminate the following faults can only be performed in a car service, as you will need a special tool and certain qualifications.
Leak from under the gasket
1. Periodically check the condition of the transmission pan, tightening of the bolts, the condition of the split plane of the pan and the gasket.
2. The causes of leakage from under the pan gasket may be an increase in pressure or liquid level due to clogging of the ventilation holes, deformation of the pan or its split plane, inconsistency of the used sealant brand with the recommended one, and defects in the casting of the pan.
Leak from under the seal
1. A packing leak can be caused by high pressure or fluid levels due to clogged vent holes, improper packing, damaged shaft seals, or worn bearings.
2. Check periodically the tightness of the seal of the pointer pipe and the speedometer gearbox.
3. If a leak is found, replace the O-ring.
Crankcase leak
1. The crankcase leak is due to casting defects, in this case repair or replace the crankcase.
2. Check that the fluid cooler hoses are secure.
Leaking breather or filler pipe
A leak from the breather indicates transmission overflow, coolant ingress, porous crankcase material, incorrect pointer position, clogged ventilation and drainage channels.
Road test
Test with selector position in DRIVE range
1. Move the selector to the DRIVE range and accelerate the car.
2. Switch the selector to positions 1-2, 2-3 or 3-OD.
3. The torque converter must lock up in 1st or 2nd gear, or OD gear. Depress the throttle pedal 3/4 of the way - a downshift should occur.
Test with selector position in RANGE 2
1. Shift the transmission to RANGE 2 while driving.
2. The transmission should downshift immediately and should not shift back to Overdrive.
3. Check downshifting at partial and full throttle.
LOW Range
1. Move the selector to the LOW position.
2. Check transmission operation.
Checking braking in different driving modes
Coasting at initial high speed
1. Move the selector to a low range gear.
2. The engine speed should increase and the braking effect should be felt.
Reverse
1. Move the selector to the REVERSE position.
2. Check transmission operation.
General Checks
1. Check the condition and adjustment of the engine.
2. Check throttle cable adjustment.
3. Check the condition of the transmission hoses and wiring.
4. Check transmission selector adjustment.
5. If, after these checks, the transmission still does not operate normally, contact a car service to check the pressure in the transmission line.