Transmission Facts and Myths

[kodiak]

https://Www.acgauto.com

Not many people would knowingly neglect something that might cost them thousands of dollars. With automatic transmissions there is so much mis-information floating around it is hard to know what to do. Hopefully this short article might shed some light.
There are a number of myths concerning transmission service. These can cost you major dollars. Here are some facts.

Myth: If I have not serviced my transmission for 100,000 miles, it’s too late or it might cause it to fail.

Fact: This myth makes as much sense as, "Since I have not brushed my teeth for six-months I should not ever brush them. A proper transmission service can never hurt your transmission and may very well extend the life. Certainly it would have been best to service it sooner. You may also find a problem that service cannot correct. Even then, prompt action can still save a breakdown and lower the cost of the repair.

Myth: Flushing a transmission will clean the filter.

Fact: Most filter elements are built much like a sock. Fluid enters this transmission filter through the neck and flows out through the fabric. Debris entering such a filter cannot come out and will eventually plug the filter. When the fluid is restricted, the transmission is no longer lubricated. A proper service includes replacing the filter on transmission that have a pan.

Myth: Material in the pan means the transmission is bad.


Fact: A small amount of fine powder-like material is often found in the transmission pan. This is from normal wear and tear and does not indicate a problem. Larger pieces of metal and any signs of water indicate a major problem. The best shops will often dissect the filter to find evidence of a problem.




Myth: Transmission fluid is all the same or this fluid is "better" than the original fluid.


Fact: Manufacturers blend specific fluids to address specific demands of a design. There are several fluids on the market and some shops may use universal of even substandard fluids. Never let anyone substitute the fluid in your transmission. USE ONLY THE OEM RECOMMENDED FLUID.

A proper service involves a test drive, removing a removable pan and inspecting the inside of the transmission. Adjustment of bands, if used and a check of valve body bolt torque is also included. Replacement of the filter and filling with the exact replacement fluid is also part of a proper service.

One way to be certain you get a proper service is to use AGCO. We specialize in proper transmission service, repair and rebuilding. AGCO, it’s the place to go!

Sent from my '85 Lincolin Town Car

[porschpow]

This is interesting writeup.

What type of ATF should you use for the AOD's? Type F??? Should you opt fo the synthetic fluid, high mileage? Or just stay with conventional

[kodiak]

IIRC Mercon V. I'd check www.bobistheoilguy.com for the rest of the questions.

Sent from my '85 Lincolin Town Car

[porschpow]

It would def be nice to have some hard facts to see why changing it so long between intervals woudl damage the tranny, you know? I do fee that under moderate accel, going into OD, I feel two clunks, not one

[LithiumCobalt]

Here's the latest transmission fluid recommendation chart per Ford. AOD has dropped off since older use, but it was Mercon V. Most everything is unless you have something in the mid to late 2000's or newer.

[gadget73]

The original fluid was Dexron II. It was superseded in the later 80s to Mercon, which is the same as Dexron III. The current chart from Ford says Mercon V, or did last it had the AOD listed. You can also use "universal" Mercon/Dexron III fluid. Type F is old stuff, used in the C6 and the power steering pump mostly. I think early C4 used it too.

[sly]

if the torque converter has clutches... merc V... if not... mercIII is fine. My AODs have mercIII, the AODE has mercV.

[gadget73]

well, basically Ford quit making Mercon, so they superseded the fluid recommendation on the AOD to Mercon V so it used a magic juice that they actually still sell. The entire reason for changing it from Dexron II to Mercon in the first place was so people bought Ford fluid for their Ford transmission instead of GM fluid.