I have a very good friend who owns a transmission shop. He tald me the transmission flush deal is great for him. After someone gets a flush, usually within 6 mos. they need a rebuild. Ford automatics have torque converter drain plugs, usually 2, 1/8" pipe thread, 7/16" hex head. You loosen one, turn the engine 1/2 turn and remove the other one. If you have the heavy duty version of the C4, the dipstick tube has a large inverted flare fitting on the side of the pan (my 77 did). Remove this, then once the fluid stops running out, remove the pan. Inside the pan is a screen (filter) carefully remove it not losing the relief valve and spring. Replace with a new one, reinstall the pan and filler tube. Reinstall the one converter drain plug, turn the engine 1/2 turn again and tighten the other plug. If I remember correctly, you pour 5 qts. of fluid in (type F, not Dexron) start the truck, and pour 2 more in, then start checking. Once you are full cold, run it through the gears, bring it back and recheck. You are done with the fuid/filter change!

 

Thanx,
__85lebaront2 I forgot about the tourqe converter drain plugs.

 

Say,
__is there anyone here that can exsplane why transmissions are prone to failer after a "flush".

I gave my ideas of how this happens.

 

I think they are prone to failure after a flush because people ignore their trans until something goes wrong. Then they get it flushed hoping that it will fix it. It doesn't. It's too late because the damage was done before they noticed something was wrong. New fluid can't fix a broken trans. If they flushed it before there were problems it would have lasted much longer.

That's my $0.02.

 

So,
__what if trans was running fine before it's flush?
Then it breaks, afterwerds.

 

That is what my friend referred to, the customer goes into a tune and lube shop, or dealership and gets talked into the transmission flush. 6 months or so later the transmission dies. Most shops that do the flush, won't change the filter. If you have something with no drain plugs anywhere, and flush the normal buildup from the torque converter (it makes a real good centrifuge) it winds up in the filter, and, due to the system design, it puts some crap in the valve body. I will stick to drain and refill with a new filter!

 

Then I don't think the flush had anything to do with it. I've flushed quite a few transmissions and none of them have failed. Some have a lot of miles after the flush, too.

 

Ok,
__that sounds about right.

 

I took this picture for a extended warranty company, it shows a clutch from a CD4E trans in a 626. The clutch material on the clutch is flaking off on the outer edges. This transmission was "working fine" and just had a small leak from the front area, they just wanted me to fix the leak but I like to do a inspection just to catch little jems like this. It turns a $500. repair into a $2k repair.

If I was to change, or flush the fluid in this trans, the new fluid with a high level detergent would have caused the rest of the material on the clutches to flake off more rapidly and the trans would start to show signs of problems. It would most likely be blamed on the flush or me for causing the trans to fail. The fluid over time breaks down and can change to a varnish state and it ability to clean.





I have built hundreds of transmissions with high mileage and no signs of being serviced and the clutches looked ok with no sign of this type of flaking. What causes this I am still not sure, I think it has to do with different types of real world conditions like heat, time, driving situations, ect. You will never know it you trans will "survive" a fluid change without inspecting the clutches.

I would have to say 1 out of 50 will be like this one. I mostly find this in early GMs like the 125, 200, 2004r and Fords like CD4E, AXODEs, E40Ds Chrysler's TF series and some imports especially 97 - 03 Honda's and Mitsubishi.

I hope this can give you some insight on what really happens when a service "causes" problems.

 

Finally,
__something rock solid.
Thank-you.

Feel free to give more, everybody.

 

they need a rebuild. Ford automatics have torque converter drain plugs, usually 2, 1/8" pipe thread, 7/16" hex head. You loosen one, turn the engine 1/2 turn and remove the other one. If you have the heavy duty version of the C4, the dipstick tube has a large inverted flare fitting on the side of the pan (my 77 did). Remove this, then once the fluid stops running out, remove the pan. Inside the pan is a screen (filter) carefully remove it not losing the relief valve and spring. Replace with a new one, reinstall the pan and filler tube. Reinstall the one converter drain plug, turn the engine 1/2 turn again and tighten the other plug. If I remember correctly, you pour 5 qts. of fluid in (type F, not Dexron) start the truck, and pour 2 more in, then start checking. Once you are full cold, run it through the gears, bring it back and recheck. You are done with the fuid/filter change!

__________________
Well, today I went out to the garage and tore into the fluid change. what you read above is what I did and it runs, shift better then it did before. Not that is was bad before, but it seems to be more solid when I put it into gear. Now granted the pan leaked a little before and it was down two quart. (been that way since I got it in August.) I bene working on it and have not put it on the road yet.

 

Glad it worked out ok for you.

 

One more question, I though of while I was in the shower this morning. The RELIEF VALVE AND SPRING. While I was taking the screen (filter) off, the spring flew and landed beside the front tire,(no problem). As I took the last bolt off, the RELIEF VALVE fell into the pan of old fluid(still no problem).

Now for the part that got me going. I put the new screen (filter) into place and put the spring up in the hole where it came out of and put the RELIEF VALVE on the bottom. (??)

Since it flew apart as I was taking it apart, I believed this is how it was. But this AM while in the shower I got to thinking how do I know the VALVE doesn't go in first then the spring. I drove it back and forth in my driveway and it ran really good and solid. The driveway is only long enough to get into second gear. (I hate these after thoughts)

 

That's,
__up to you. If you feel that it's good, ok.
From what you said the spring went in first. & it's been some time for me. So, I'd go ask a ford transmission tech ( it dosn't cost anything to talk to them.)about it before you drive it anywhere.

 

The valve goes in first followed by the spring.
The filter presses against the spring and holds it all together.