(I bought this truck from a rural "truck mechanic", or at least the young fellow was trying to make a living that way. It had been in storage for several years after the original owner's retirement from farming, and picked up by the "mechanic" after the owner's widow's death.)

This new to me 1970 F-100 - with a 1975 Granada 302 engine - needed brake and carburetor rebuilds before being run or driven after purchase. After those were both successful I went to an experienced local Ford mechanic, who fine tuned the carburetor to a nice smooth idle and told me the transmission slippage I was experiencing was not too serious. About 15 miles later, while showing off the truck to my granddaughters, I lost all three forward gears.

Checking the transmission fluid, I found it overfull by three inches above the hot line. Overfilled with bright, clean looking ATF fluid.

We towed it back to my place. Checking the transmission from under the vehicle it appears to be leaking from the rear seal, the shift lever, and the pan gasket, although there is so much fluid down there it's hard to say where it is coming from. The coolant lines and vacuum modulator may be OK, I cannot tell.

Help I need; your opinions are welcome:

Can the excess fluid be removed by a fluid extractor pump for this transmission?

Is there any point in simply removing the excess fluid? That is, has the transmission been so damaged by being driven with excess fluid that it must be replaced (or possibly rebuilt)?

Is there any reason to "drop the pan" to drain the fluid, instead of using a fluid extractor pump?

If removing the excess fluid has no possibility of restoring forward gears, then should I carry the truck to the local mechanic to have the work done, or go "over the hill" to a transmission specialist or Ford dealer in a larger community? (I don't do transmission work myself.)

 

Spent some time chatting with parts people and mechanics; arrived at this point:

The excess fluid did not come from the t. converter, and the problem is not the front pump; loss of either of those would take out reverse as well as the forward gears.

With this much excess fluid it is possible that aeration of the fluid reduced its viscosity to the point it did not perform; but the fact that reverse is still working seems to counter that possibility.

In a truck stored as long as this one, the fluid may absorb water and become very acidic, making the clutch materials in the transmission brittle and weak. The forward gear clutch may have failed.

Next steps:

Use a fluid extraction pump to reduce ATF fluid to the correct level. One of the people I spoke with suggested that 3 extra inches on the stick indicated that at least two quarts should be removed.

If no joy, then pull the pan, and inspect for clutch fragments, or other indications of failure of mechanical components of the transmission; be prepared to have the transmission rebuilt, or at least have the clutch repaired. (Recommendation was against replacement.)

Whether this C4 transmission needs Type F or Mercron III ATF is in question; check for a tag on the rt. side to determine series which may be helpful in deciding which ATF to use.

That's it until tomorrow.

 

If the trans fluid had water in it the color would be similiar to a strawberry milkshake.
You can remove the cooler line from the radiator (the one coming from the front of the trans, not the rear) connect a section of hose, put the hose in a bucket and briefly run the motor until you think 2 quarts have been pumped out. The trans being over full aerates the trans fluid causing the fluid to lose it's hydraulic properties which then does not allow the fluid to fully apply the clutch pistons which causes slippage and excessive heat (heat is the worst thing for an automatic trans). Get the fluid to the correct level and then evaluate the transmission. It's possible that the forward clutch has already been damaged.

 

If the C4 is from a 1975 or 1976 Granada = Type F ATF.

1964/76 C4 & 1966/76 C6 = Type F ATF

1977 and later C4 & C6 = Mercon.

 

Bobby, Bill, I'm very grateful for that information.

I've shot the transmission casting tag, and will post the photo later, it reads "PEA K8 / D3TFB"; Wikipedia tells me that this is a part of the "1971–1979 Select Shift, 26/24 spline, castings: D1, D2, D3, D4, D5, D6, D7, D8, D9" family. The transmission is apparently of later mfgr. than the truck body; it possibly came with the engine.

The pan, fill tube, and dipstick are of the pan fill variety. I can only hope that they are correct for the transmission, until I find more information about the configuration of the Granada trans.

The improvised linkage between the pickup truck in-cab shift mechanism and the grafted transmission may be responsible for difficult & noisy shifting, and trouble telling what gear the vehicle is actually in.

Based on the Type F spec for the transmission, and the probability that Mercon was added when the truck was taken out of storage, I have used a fluid extraction pump to remove as much fluid as possible.

According to most advice I've received the next step would be to "drop the pan" to drain the rest of the fluid. But to do that I'll have to remove the filler/dipstick tube, which will drain the pan. The only point in pulling the 11 pan bolts would be to replace the pan gasket; I'm inclined to let that go for the time being. ???

Edit: I have posted the trans. photos at https://www.ford-trucks.com/forums/a...ictureid=40821 with a question: What are the apparent bolt heads in the side of the transmission case above the pan for?

 

If you've used a pump with a tube down through the dipstick tube, and you think it was hitting the bottom of the pan, then you probably have most of the old fluid out. The next step is to refill it correctly with Type F, and try it out. As the others have said, the real damage is caused by heat from trying to drive it while the clutches are slipping. It may have aerated out the oil and stopped applying before any clutches got burned, or it may not. You'll just have to test it to find out.

If it drives okay, then I'd give it 100 miles and change the fluid again, just to make sure all the old stuff is out.

 

Long bolt with the square head, with the hex nut against the transmission will be for a band adjustment.

Small bolt above the pan is possibly the bolt removed to hook up a transmission oil pressure tester.

IMO (In my opinion) anyone has to be a total...well...never mind. It's not worth the effort to just change the fluid itself. Pull the dipstick from the pan as stated to drain the fluid, and then drop the pan and do a correct job with a new filter. Once the pan is dropped? You can really see what's going on, judging by the amount of crud--or lack thereof...in the pan itself. Yeah it's more work and slightly more expensive for a pan/filter kit--but consider this: Would you just drain your engine oil, and leave the old filter in place??

S-

 

On a C4 there are two bands to adjust. One is the low-reverse band, one is the intermediate band. The low-reverse is the rearward most band. To adjust either, back the lockdown nut off of the square headed bolts and tighten the bolts to 10 ft. lbs, then back the square headed bolt out 1-1/2 turns for the intermediate band and 3 turns for the low-reverse band.

 

Tedybear, if the truck was driveable and not possibly headed for a transmission rebuild, I'd agree on the filter change. But with no forward gears?

I am considering two possibilities right now, for the reasons given below. One is that this pan, fill tube, and dipstick do not belong with this transmission, the readings on the tube are just wrong, and there is too little fluid in the transmission despite what the dipstick reports.

The other is that all of the ATF in the transmission is in the pan, and little to none in the torque converter, and that somehow reverse still works while the forward gears do not work at all. (Bobby's latest raises the possibility that the low reverse band is more accurately adjusted than the intermediate band, but I'm still chewing on that one.)

Here are the results of my testing today.

When I pumped out the transmission, expecting to get in excess of the rated capacity of 5.5 qts. because of the overfill reported on the dipstick, I got about one gallon of clean, somewhat dark, and pretty burnt smelling fluid. That's it. I had the pump tube down to the curve of the fill tube, where it turns to enter the pan, so should have emptied or nearly emptied the pan. And got only 4 qts. out.

Believing I had emptied the transmission of fluid, I prepared to add 5.5 qts. to it to bring it to spec. fill. I added 3 qts., and checked the dip stick, cold, engine off. As I expected, the stick showed overfull. I started the truck, left it in Park, and let it warm up. As it warmed up I checked the dip stick. The transmission fluid level showing on it droppend only slightly. I have the truck up on blocks, so ran the transmission through the various gears. Reverse gave a positive response. Neutral, Drive, and 2nd all showed some rotation of the wheels, but not strongly. Low stopped the rotation.

After the engine was hot, and the transmission warmed significantly (not 180°) I checked the dipstick. It showed 1.5 inches over full - with 3 qts. of Type F ATF added to what should have been an empty or nearly empty pan.

I do not know enough about transmissions, and this transmission to evaluate what these observations might mean, apart from the speculations I described above.

I may need to pump out the 3 qts I added, and then pull the fill tube off the pan to drain any additional fluid that is in it, and then pull the pan. But if what I describe indicates some mechanical failure, such as of the front pump, and the transmission is going to be rebuilt, I'll skip that as pointless. Do you folks have any other suggestions?

 

Where did you get the 5.5 quart capacity specification? Excluding converter?
C4 with an empty converter should hold 8 quarts.

 

Yes, the 5.5 excludes the converter. I have the idea that the converter does not drain when draining the transmission, so I should expect to drain and replace the 5.5 qts. Please correct me if that's haywire.

I've decided to trust specs and measures, instead of the dipstick, at least as an experiment, and put in 5.5 qts, no matter how overfilled the stick says it is. Perhaps the stick is wrong, and the specs and measures are right, in which case I was running low, not overfilled - which is compatible with the fact that I pumped only 4 qts. from the transmission. But that's for tomorrow, and I'll appreciate anyone's thoughts before I do it.

 

If you pull the inspection cover and rotate the motor around there is a drain plug on the converter near one of the converter/flywheel mounting nuts.

 

I agree that, from what you're describing, there's a good chance that it's underfilled, and you're just getting false dipstick readings. If it's actually down two quarts, then it could behave funny like that. If it were mine, I would add one quart, try it, then add another and try it. That way, you'd know that you have at least 5 quarts (plus what's in the converter) in there. If that doesn't work, well, then you'll know that something has actually blown out and the transmission has to come out and apart.

 

This C4 is not from a Granada, or any other passenger car.

PEA-K8 / D3TP-FB = Original application: 1973 F100 302.

These two codes are listed on the TRANS ID tag, they are not casting numbers.

These two codes were found here (not on Wiki Wiki!): 1973/79 Ford Light Truck Parts Catalog / Transmission ID & Application Charts / Text, Section A70, page 4.

C4's take 11 total quarts of ATF.

Look on the dipstick for its ID engineering number, which if it's the original will be the following:

Marked with an ID number of: D3BP-AA = Ford part number: D3BZ7A020A .. A/T Dipstick

Fits: 1973/74 F100 302/C4 & 1973/74 Bronco 302/C4.

 

Bill, thanks very much for the information & corrections. The dipstick number is as you say D3BZ7A020A

The transmission tag on the case (not the casting, my error) is shown here Ford Truck Enthusiasts Forums - Jim Pivonka's Album: Ford Pickup Truck - Rebuilt - Picture

The fact that this C4 should have 11 and not 8 qts. of ATF helps explain why I got 6 qts. from the converter drain, instead of the 2.5 I expected. More on that in my response to Bobby's earlier comment.

EDIT: I read your information to imply that the dipstick, fill tube, and pan attached to this transmission belong to it, and cannot account for or lead to any misreading of over or under filling of the transmission with ATF? Is that correct?