Automatic Transmissions: Care and Repair
Repair of an automatic transmission can mean a considerable expenditure for the car owner. Since a transmission is a concealed item, most Transco Transmissions customers never see the work that is done, and probably wouldn't be able to evaluate it anyway.
Therefore, it is wise to give your transmission proper maintenance, and to be an informed customer if and when repairs are needed.
Purpose of a transmission
A transmission is only a coupling between the engine and differential and its purpose is to transmit engine torque to the driving wheels. This is done through a number of reduction gears and the use of a torque converter (fluid clutch). Transmission performance can only be as good as the power supplied to it (engine), and the driving members to which this power is transmitted (drive shaft, differential). A ROUGH RUNNING ENGINE CAN ONLY RESULT IN A ROUGH SHIFTING TRANSMISSION.
What is inside your transmission
All automatic transmissions use a combination of friction materials (similar to paper or cardboard) bonded to metal plates and bands, rubber or neoprene seals, and bushings. These parts are considered soft parts, and will eventually wear out from normal usage. When these seals lose their flexibility and the friction materials and bushings become worn, slippage and other malfunctions become apparent. If these conditions are not corrected, more serious wear then occurs to the hard parts (metal drums, gears, and pumps) of the transmission.
Prevent transmission trouble before it starts
(How to prolong the life of a transmission and prevent trouble)
The cheapest, simplest way to prolong transmission life and avoid trouble is to change transmission fluid frequently and change or clean the filter or screen. This is the advise of knowledgeable mechanics who explain that the inhibitors in transmission fluid deteriorate with use. These inhibitors are specific formulas in the fluid that are designed to protect the internal parts of the transmission. When the inhibitors deteriorate, wear on these parts becomes excessive and trouble results. Fluid also becomes contaminated from deposits of worn off bushing and washer materials, and clutch plate linings. Although new car manuals generally ignore this important precaution, frequent, fresh fluid is mandatory. Transmission fluid should usually be changed from 10,000 to 15,000 miles if the entire system can be drained - from 5,000 to 8,000 miles if only the pan can be drained, depending on severity of use.
Check the transmission fluid regularly! If the unit is only as much as two quarts low, the transmission will start to slip and slippage causes heat. Heat, in turn, speeds the deterioration of the inhibitors in the fluid.
Transco states Forcing the gears to shift at maximum acceleration is just asking for trouble.
If you frequently pull a trailer you should have an external transmission cooler installed. Pulling a heavy load causes the transmission to labor, building up heat, and such a device cools the fluid. Even with a transmission cooler, fluid should be changed more regularly - probably every spring and fall - if you haul a trailer very much. Also, it's a good idea, when pulling a heavy load, to manually select the proper shift position so that frequent automatic shifting of high to intermediate and back is avoided. This will help prevent foaming and overheating of the fluid.
Symptoms of transmission trouble
On most late model cars, the sift is controlled by vacuum supplied by the intake manifold of the engine. If your car won't shift or shifts erratically, the vacuum modulator (a small, inexpensive unit) may not be functioning properly or the vacuum line to the transmission might be ruptured. Such repairs are inexpensive and quickly completed.
In order for a transmission to operate properly, the car's engine must be in good running order. Often rough shifting and other problems can be corrected by a simple tune-up of your car's engine. Remember, transmission performance can only be as good as engine performance.
If your transmission cannot be shifted at all, or the shift handle is hard to move, it is possible your car's engine or transmission mounts are broken or the transmission levers or linkage need repairing and nothing is actually wrong with your transmission.
One symptom of serious trouble is slippage between gear shifts - the engine races between shift changes. This can be caused by low fluid level or improperly adjusted throttle linkage, or by glazed or burned clutch plates which requires that the transmission be overhauled or replaced.
Those puddles of transmission fluid on your driveway could mean your transmission needs new seals. This NOT a major job, but prices to have the work done will vary depending on make and model. LEAKS MAY BE CAUSED BY PROBLEMS OTHER THAN SEALS. LEAKS MANY TIMES DO NOT INDICATE A SERIOUS PROBLEM. ON THE OTHER HAND, LEAKS MAY BE THE RESULT OF A MORE SERIOUS MECHANICAL FAILURE. An inspection by a qualified mechanic is the only way to tell for sure. The important thing Transco Transmissions advise is - get those leaks stopped as soon as they become apparent, or major trouble is almost surely to develop.
Remember these precautions:
Quite often transmission problems are caused by improperly running engines, broken transmission or engine mounts, leaking vacuum lines, or low transmission fluid level. Therefore, make sure that these items are in proper order before condemning your transmission.
Do not be deluded by low price "adjustment" advertising. Most late model cars cannot be adjusted at all, and on most others, only a minor adjustment is possible. Transmission servicing and adjustment is a maintenance procedure only, and will very seldom (if ever) correct any malfunctions.
Have a mechanic road test the car and make an external inspection. He should be able at that time to tell you whether the problem can be corrected by a minor adjustment or repair, or will require more extensive repairs. If he prescribes a major job, he will be able to tell you only the minimum and maximum that you may be charged.
The minimum price would probably be for an overhaul, replacing only the friction materials, or soft parts. The maximum price will be for a completely rebuilt or exchange transmission. Make sure that you clearly understand whether or not the quoted price includes both parts and labor, as well as a rebuilt torque converter - many times a very necessary item. Be skeptical of a low price for what seems to be a major problem.
An estimate as to the cost of transmission repair can be give in cases where external observation and/or a test drive permit an accurate diagnosis of the defects. If an accurate estimate is not possible, none should be given without internal inspection. The firm should stand ready in every case to reassemble the transmission in its original condition at a price clearly stated to the customer for this inspection before his transmission is disassembled.
Inquire into the nature of the guarantee included with the work. What is covered and what is not? Extra cost guarantees or higher-priced transmission with longer guarantees attached should be considered carefully. A guarantee is only as good as the company which offers it.
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