Awesome BH, Thank you.. I freakin missed your response.. What a dummy..
You are The MAN...!
These are notes from another thread from the C4 God..! ;D
You had a cork & metal clad gasket. I dont think that type is available any more but Napa used to sell them under the Victor product line.
Another tip, throw that rubber gasket in the garbage, it is worthless. You wont be happy with its performance. I usually buy the cork gaskets from Transtar but your local transmission shop should have them.
Here's more...
C-4 Transmission Pan Gasket Service for stock steel pans:
When removing the pan use a 7/8” flarenut wrench to get the dipstick tube loose first before loosening the pan bolts. Make sure all the pan bolts are the Ford flanged type. The incorrect pan bolt can also cause leaks due to improper or uneven clamp load in the areas surrounding the bolt holes. Choosing the right type of gasket is important. Paper gaskets are not as friendly when used with older vehicles and usually require over-tightening of the pan bolts to make them work.
I have never seen a rubber pan gasket that didn’t leak on a C-4 no matter how tight it was. As far as I’m concerned, any C-4 pan gasket that comes folded inside a box from a part store is absolutely worthless. Go to a transmission specialty repair shop and buy a cork gasket, and any other supplies if needed. The best way to prevent leaks is to spend some time preparing the gasket surfaces. The trick to making the pan seal is to make sure the pan surface is flat and free of any stray gasket material.
I have a wire wheel on my bench grinder for getting these clean. A dry gasket surface, free of oil and dirt is important. Most all transmission pans on trucks this old will be distorted on the gasket surface. You will likely need to straighten your gasket surface on the pan before reinstallation. The pan can also get distorted by using a paper gasket because you have to over tighten them in order to get them to seal. I usually straighten pans with a special punch that is larger diameter than the bolt hole but ground to a very shallow cone. The back of a ball peen hammer also works well for this. Brace the pan rail from behind with a straight block of hardwood, steel, or the edge of a workbench.
By using a hammer with this punch you will cause the bolt hole to go beyond being flat and just a little concave on the gasket side. But when you tighten the bolt it will draw the gasket surface on the pan flat again. Using the hammer, straighten any other distorted edges so as to make the gasket surface straight and level. When tightening the pan, the same torque spec will not work with all gaskets because of different gasket manufacturers. For this reason I tighten them by feel and by sight.
When the gasket starts to bulge just slightly around the bolt that you are tightening, that is usually enough. The important part is to get them all evenly torqued. Draw the bolts down evenly, and do not over tighten. You will need to go over them 3 times to get them all evenly torqued. A speed handle is my favorite tool to do this. Use no sealer with a cork gasket, if you managed to get the pan surface straight with a hammer and punch that I mentioned, and it is clean, dry, and free of oil, it will seal properly without a problem. I have the best success installing cork gaskets dry. If you must use sealer, use Gasgasinch.
Apply the sealer to both sides of the gasket as well as the sealing surfaces and let it dry to a haze before positioning the gasket and installing your pan. Whatever gasket type you decide, careful preparation must be taken before and during installation.
Regarding the hump in the botton pan:
This pan was designated on all C-4 equipped with ford trucks that were 4x4s. All Broncos and some Econolines with the pathfinder conversions had the extended sump. The deep sump is needed in order to keep the transmission pump from starving for fluid on steep inclines and declines. The Deep Sump must also be used with the exclusive Bronco Filter and sump pick-up pipe assembly. Flat bottom pans were not factory equipment in 73-77 EBs.
Filter & relief valve:
When changing the filter try to use a filter gasket It is better to include a filter gasket but not critical. When removing the filter be careful when loosening the last bolt. You will find a spring and a valve pushing the filter away from the valve body. Do not lose these vital pieces and make sure they get installed in their proper order.
Sump Pick-up Pipe
When you change the filter that has the rubber grommet, you clean and reinstall the pick-up pipe onto the new filter. When I bought my 73 some dumbass failed to reinstall it (probably threw it in the trash with the old filter) and I had to buy a good used one from Jeff’s Bronco Graveyard and it wasn’t cheap. Without the pickup pipe it will be necessary to slightly overfill the transmission to get proper clutch and band engagement. Overfilling is not recommended but in a pinch it can sometimes keep you from being stranded.
The Hi gear Pressure relief Valve:
When installing the filter, the little valve goes into the channel first with the cup facing the valve body and the little peg resting inside the coils of the spring. Then install the filter and bolts positioning the retainer tab over the spring to hold it in place. Some C-4s have a ¼” steel ball instead of the valve in this location, these setups work fine but are not factory equipment on any C-4. The steel balls usually get installed when the technician looses the valve. ¼” steel balls seem to be more common than the valve and readily available in most transmission shops.
Filter Bolt Torque:
Tighten the larger valve body bolt to 9 foot lbs. and the smaller bolts with the 5/16” head using a nut driver. Now you are ready to install the pan.
I wish you much success with your do-it-yourself maintenance.~BH~
