4+3 Transmission Service

[McSnagg]

I have an 88 I purchased late last year with the 4+3 transmission. I have yet to service it. What is the correct service procedure and interval?

Thanks!

 

[c4cruiser]

I would replace the OD fluid and filter about every 15K miles and more frequently if you autocross or do track days. The OD fluid is Dexron II/III auto trans fluid and takes about 2 quarts.

The filter is the same one that's used in Ford FMX automatic trannies from the early to mid 70's. Don't bother buying the filter from the various accesory catalogs for $30. Get a Carquest filter #85926 for about 6-8 bucks. You can probably cross-reference this filter to Fram and others for about the same price.

Remove the bolts on the oil pan except for a couple at the rear. Break the seal at the pan and let the fluid drain into a catch tray. You can remove the fluid in the cooler lines with a few psi of air pressure but it's not really necessary. Carefully pull the filter from the rubber grommet and replace with the new one.

Clean the pan and OD housing mating surfaces and make sure the pan rails are straight. You can use a black RTV sealant in place of a gasket as long as the surfaces are clean and free of oil or solvents. There is a fill plug just above the pan rail that is removed to add new fluid. Use a hand pump to add the fluid.

If you clean out the fluid in the cooler lines, you can replace that fluid as you fill the OD pan. With the rear wheels off the ground and the shifter in neutral, simply turn a rear wheel for about a minute. That will pump fluid thru to the cooler lines. Top off the unit until fluid begins to drain from the fill hole and replace the plug.

The 4-speed portion uses 80W-90 GL4 gear oil. Takes about 2-2.5 pints. To drain, remove the lower plug on the tranny case. Once the old oil is drained, replace that plug and remove the one that is about a third of the way up the side of the case. Fill with fresh gear oil until it just begins to run out of the hole and then replace the plug.

 

[McSnagg]

Does the gasket that comes with the filter fit the pan?

Thanks for the great overview!

 

[c4cruiser]

I think that the Eckler's filter kit includes a gasket but that kit os over $30 by the time you add their shipping and handling charge.

The Carquest part number is actually for a Ford FMX tranny and there is no gasket included for that application no matter what Ford or Mercury car or truck used that ffilter.

I use the black RTV sealant and as long as the pan and tranny case mating surfaces are clean of all oils and grease, it works fine.

One thing I found is that while non-chlorinated brake parts cleaner does a good job of cleaning the surfaces, if you use too much you will leave a film on the surface and the RTV may leak or not stick. Use denatured alcohol to remove any trace of cleaner from the mating surfaces and the RTV will stick fine.

Make sure that the pan rails are flat and don't use too much sealant. Don't tighten the screws too tight and be careful to get them tightened equally.

 

[McSnagg]

I checked with my local CARQUEST store today. The filter number was not in stock since it is such a slow mover. I did find out that their main transmission parts line (Pioneer) showed the same filter with a brass filter screen instead of felt. The book said a brass screen filter was OE. The part number I oredered is PIO 746001.

Thanks again!

 

[tdr1919]

I think that the Eckler's filter kit includes a gasket but that kit os over $30 by the time you add their shipping and handling charge.

The Carquest part number is actually for a Ford FMX tranny and there is no gasket included for that application no matter what Ford or Mercury car or truck used that ffilter.

I use the black RTV sealant and as long as the pan and tranny case mating surfaces are clean of all oils and grease, it works fine.

One thing I found is that while non-chlorinated brake parts cleaner does a good job of cleaning the surfaces, if you use too much you will leave a film on the surface and the RTV may leak or not stick. Use denatured alcohol to remove any trace of cleaner from the mating surfaces and the RTV will stick fine.

Make sure that the pan rails are flat and don't use too much sealant. Don't tighten the screws too tight and be careful to get them tightened equally.

C4 - how important is it to have the car level?

 

[douglas foster]

father & son

Asked chev dealer trans repair specialist ,if just sucking out old over drive fluid and replaceing, was ok. I only put on 3-4 thousand a yr. He said"was fine filter should be at 15000 mi. cycle though". Remember the fluid is the most important and try and change once a yr.

 

[c4cruiser]

C4 - how important is it to have the car level?

Keeping the car level will insure that you get the right amount of Dexron fluid in the car. When I change my filter and fluid, I put the car up on jackstands at each corner. That way it's easier to get under the car to work on it.

McSnagg- The filter screen should be brass (or some type of metal). I ordered one filter from Mid-America and then bought the Carquest filter. Holding them up side-by-side, they are exactly the same piece. I have never heard of a "felt" version.

Douglas-- If you only drive those short miles per year, you might want to check with a tranny shop to see if they can add a drain plug to the pan. It would be a lot easier to unscrew a drain plug than trying to suck out the old fluid.

The pan also has a magnet at the bottom (or at least it should have!!). The magnet holds metal filings and it should be cleaned each time the fluid is changed.

 

[6 Shooter]

Doug - I know I'm replying real late: What A Great L@@king Engine Bay!

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[douglas foster]

father & son

Thanks for the reply,it's only elbow grease.

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