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Should I use synthetic fluids in my transmission, or differential?
Should I attempt to overhaul my own transmission?
Where do I get an overhaul manual for my automatic transmission?
How can I disable 'dem darn electronic controls on my transmission?
My car makes this sound.... or this vibration.... What is causing it??
How do I figure out what rearend ratio to run?
How do I figure out what stall speed torque converter to use?
Should I make an automatic transmission shift harder?
My AODE transmission (late model Ford rear-wheel-drive cars and 1/2 ton trucks) shudders when shifting into lockup. Answer: Many do, after 40,000-60,000 miles. This is caused by a glazed torque converter clutch. Ford has a bulletin that involves replacing fluid, and flushing the transmission with new fluid, to completely change out the old fluid, to correct this problem. I believe this to be a pathetic attempt to get Ford owners off of their backs (this is only my opinion...), but this does seem to help eliminate the shudder temporarily. In my opinion, the only "fix" is to overhaul the transmission and replace the torque converter with an "updated" converter, by Ford; this will keep the shudder away, usually, for a longer time, than the transmission lasted originally. As of this time, I know of no "complete and definitive" cure, that will keep the shudder away for 100,000 miles, like I feel a transmission should last.
My E40D transmission (late model Ford trucks) shifts sloppily.
Will the AOD transmission hold up if I install a "high powered engine" and large tires?? Answer: Probably not. The AOD has never been noted to be a strong unit, and does not hold up well, in my opinion, when subjected to high torque, and horsepower conditions, and is actually marginal, in "e; Stock "e; conditions.
My GM transmission (Th 350, 400, 700) quit upshifting. No matter how fast I go, the transmission remains in first gear. Answer: It is quite common for the governor gear to strip, causing the governor to "think" that the transmission output shaft is at a stop, at all times. When this happens, it is often possible to replace the plastic governor gear, to repair the transmission. It is also common for the governor to "hang", but this problem is usually more serious, as valves rarely hang without debris, from a failing part, being present in the unit. When this happens, it is usually time to overhaul the transmission, to completely eliminate the debris causing the governor to "hang".
How do I install a disable switch on the lockup circuit, so I can control my lockup torque converter manually? Answer: Why would you want to? The stock configuration cancels lockup at full throttle, and every other condition that would make it desireable to cancel lockup. Torque converter clutch "lockup" is vital to transmission life, often eliminating excessive heat generation within the torque converter, that has become more of a problem with the higher final ratios used in most cars today. There are no advantages to installing a switch to cancel lockup, but there are disadvantages: If you should forget to enable the lockup switch that you have installed, the converter will remain in the unlocked position, which will create more heat, at cruising conditions, costing plenty in gas consumption, and shortening the life of the transmission.
Should I install a non lockup torque converter in my 700R4? Answer: Not in my opinion. The main advantage to installing a 700R4, or any other overdrive type transmission in a vehicle is to reduce engine RPM and gas consumption. Many people think that the gas mileage increase enjoyed by a 700 installation is completely due to the decrease in RPM, but nothing could be further from the truth, and in some cases, lugging the engine Decreases Gas Mileage; most of the gas mileage gain, created by a 700R4 transmission, is because of the lockup torque converter. Torque converters generate heat, at low RPM; generating heat requires fuel. Enabling a torque converter clutch "locks up" the torque converter, eliminating this heat generation, which saves fuel, and lengthens the life of the transmission, fluid, etc., and, also decreases engine RPM (by the amount the converter was slipping before converter clutch application. Install a non-lockup torque converter, in a 700R4 transmission, and you will be throwing all of the benefits away, and gathering some real disadvantages. A good, well trained technician knows how to make a 700R4 work well, and be reliable, with a lockup torque converter, while lesser experienced mechanics, tend to disconnect things they do not understand.
Will my transmission hold up if I install a "high powered engine" and monster tires? Answer: Probably not. The 700R4 happens to be one of my favorite transmissions, but at one time it was not. In '82 when they first came out, they were a virtual nighmare! We could not keep front seals in them, the 3/4 clutches would burn in a short time, rear ringgears would break, and torque converters would fail, and we just did not know what to do to make them last. Since then, I have learned a lot, on my own, by attending seminars, and reading periodicals, I have learned how to make them last quite well, under "e;Reasonable Conditions"e;. 700's work very well, for a reasonable street machine, and, if driven carefully, and sensibly, they can be reasonably reliable under horsepower figures beneath 250HP. If you are building an engine to produce substantially more horsepower than this, I do not believe the 700R4 is for you. The 700R4's geartrain is physically not capable of handling excessive torque/horsepower.