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Servicing a C4

Gas_Pumps

New Member
My C4 was rebuilt about 20 years ago and has less than 8000 miles on it. Who sells the correct filter and gasket for these old C-4s? What type of fluid was most likely used after the rebuild? I have heard that no friction or rebuild kits were made for FA fluid after about 1990 - is that true?
 
My C4 was rebuilt about 20 years ago and has less than 8000 miles on it. Who sells the correct filter and gasket for these old C-4s? What type of fluid was most likely used after the rebuild? I have heard that no friction or rebuild kits were made for FA fluid after about 1990 - is that true?
C4's don't have a true "filter" it's just a screen. You can clean it and reuse it unless it's really nasty. The pan gasket (and filter) is available at any auto parts store (might have to wait a day or two to get one though). My son got his at Auto Zone. As for the fluid, since it was rebuilt and had clutches and bands replaced, the use of Type F is not as important. Type F is a stickier fluid, with friction modifiers that provide firm clutch and band engagement, which also means longer service life. What I have found is that generally it is suggested to use Mercon V synthetic fluid if Type F is not available. Mercon V is compatible with all kinds of automatic transmission fluid types. But both Auto Zone and Advance Auto in my town carry Type F. I have even seen it at Walmart.
 
Thanks for the help. Had totally forgotten what they put in it if I ever knew. Turns out that the same transmission shop is still there and has some older mechanics that understand C-4s. Most younger techs give me a blank stare when I mention C-4.
 
My C4 was rebuilt about 20 years ago and has less than 8000 miles on it. Who sells the correct filter and gasket for these old C-4s? What type of fluid was most likely used after the rebuild? I have heard that no friction or rebuild kits were made for FA fluid after about 1990 - is that true?
You could do what I did after destroying 3 of them n install a top loader.
 
Just did the C3 on the T-bird, similar construction to C4 and OEM to 1984. Got the filter and gasket and OEM Motorcraft brand Type F ATF on Amazon. If the trans hasn't been maintained over time, 8K is also a good time to run the bands. If choosing to do so, I'd get new tensioner lock nuts since moving the OEM nut might mess up the seal ring on them. Also, if practical, and having a dipstick tube which uses an o-ring, replace that as well. Dipstick o-rings, when old, can cause pesky minor leaks. Another weak spot is the shift/downshift sector shaft o-rings but those are usually more forgiving

I drained the converter as best possible and it took a bit over 8 quarts to refill. Some folks flush the cooler lines (the T-bird has an OEM external cooler) but I didn't.

Operations per normal since. The unit was long, long overdue for service but I inherited the car so wasn't in control of it. Still, the fluid drained looked clean and smelled fresh and there was very little residue in the pan.
 
Just did the C3 on the T-bird, similar construction to C4 and OEM to 1984. Got the filter and gasket and OEM Motorcraft brand Type F ATF on Amazon. If the trans hasn't been maintained over time, 8K is also a good time to run the bands. If choosing to do so, I'd get new tensioner lock nuts since moving the OEM nut might mess up the seal ring on them. Also, if practical, and having a dipstick tube which uses an o-ring, replace that as well. Dipstick o-rings, when old, can cause pesky minor leaks. Another weak spot is the shift/downshift sector shaft o-rings but those are usually more forgiving

I drained the converter as best possible and it took a bit over 8 quarts to refill. Some folks flush the cooler lines (the T-bird has an OEM external cooler) but I didn't.

Operations per normal since. The unit was long, long overdue for service but I inherited the car so wasn't in control of it. Still, the fluid drained looked clean and smelled fresh and there was very little residue in the pan.
 
Hope you got moved OK. Talked with you several months ago about gentleman from Bakersfield that got my 65. Hope he found a good group up there. Have not heard from him recently. Thanks for the advice on the C4. The shop that rebuilt it is still there and have techs old enough that you don't get a blank stare when you mention C4 or Type F. Appreciate the advice. Will make sure they do all of that. Thanks again.
 
Oh, if not already done, remembering when I bought my D-code decades ago, the first trans service after I bought it I picked up a ten dollar shift kit from one of my customers whom I modified transmission parts for and stuck that in there too. Still going strong nearly 30 years later with one service in the interim. The shift kit firmed up the shifts but it also improves clutch/band life. The trans in the D-code is OEM with about 220K on it now. One plus is it has the OEM solid intermediate band, not the flex one often included in service kits. They usually last longer.
 
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