I had my transmission go out in november. I am finally deciding to replace it. It is a c-4 mated to a 302 in a '70 f-100. As some of you may know, these trannys come pan-fill in these trucks. I am looking on summit and TCI's c-4 which is pan-filled says 'fits large bell housing only' and the case-filled one says' fits small bell housing only' So my question is would I be able to put a case-filled transmission in my truck? or are they not in fact interchangeable? I would like to do this as my headers are within about an eight of an inch of my dipstick currently. Also, what exactly is the difference between small and large bell housings as it seems they can both fit the same engines?

Thanks!

 

What the hello is pan fill??

Don't think you can exchange the trannys, not as up on my 5.0s but I believe the big difference is the bolt pattern to the engine. 5 or 6 bolts, I suspect the small is referring to the 5 bolt older model.

Someone that knows more will be along shortly to confirm.



John

 

It has to do with the location of the oil fill/dipstick tube. Case-filled means the tube goes directly into the case, pan-filled means it goes down and attaches to the pan. It curves way out to the side so I can understand the header clearance issue.

The large bellhousing/pan-filled C4’s are normally found in trucks, vans, big-bodied cars like the Galaxy and Torino, and cars with larger engines. Small bellhousing/case-filled C4’s came in the small cars like the Mustang, Granada and Fairmont with smaller engines but of course, as with all things Ford, this is not a hard and fast rule and there are exceptions.

The issue that I see is that since C4s have removable bellhousings, you need to make sure you don't wind up with an incompatibility problem. The pan-filled type large bellhousing can’t be installed on a small bellhousing case-filled type case, so if you get a case-fill tranny you're going to need to get a bellhousing to match if the tranny doesn't come with one. Also, there's a bulge on top of the pan fed case which could cause floor pan clearance issues.

The difference is between large and small bellhousings has to do with flexplate size, small being for the 157-tooth flexplate and large being for the 164-tooth flexplate. There was a large bellhousing made for the case fill, passenger car version of the C4 that will interchange with the small bellhousing. It would be found on some full size cars like a late 70's LTD or Crown Vic or possibly even a T-Bird as long as they were originally equipped with a 302 and C4. Might be easier just to to swap to a 157-tooth flexplate. If you do, make sure you get a 28oz. version so you don't wind up with an imbalance problem.

 

like said above two diffirent flex plats if you want a case fill change your flex plate also. the shim plate may be different they move the starter in.

 

Thank you for all the help here. Seeing as I would need to get a new bellhousing either way apparently, it would probably just be better to get one which fits the 164-tooth and a case fill (which I have found on summit for about $100). Another question I have has to do with the torque converter. When my transmission went out I only had about 500 miles on a rebuilt torque converter so I wonder if it would be a good idea to reuse this one or should i replace since I'm not sure what exactly went wrong in my transmission? Another thing I wonder is would it be better/easier/cheaper to just get a new/rebuilt one? or have someone clean out mine?

 

there are two case fill c4s.the early ones you talked about with small bell and flywheel and later ones in the gernada which have a large bell and flywheel like the base fill ones.all are interchangeable as long as you have everything that goes with them.

 

Don't re-use a tq. converter from a tranny that's gone out...it's liable to have debris in it that will ruin your new tranny. I don't think a tq. conv. can be flushed enough to get it all out, too many nooks and crannies inside to catch the crap and hold it. Not worth the risk.

 

I had mine gone thru by a trans shop they send them out to be opened up and inspected cost was $100.00 cheaper then a new toque converter.

 

John, 5 bolt bells apply to the early 221, 260 and 289 small blocks. The change to 6 bolts was in '66 or thereabouts. The 302 came to be in I think '68.

 

5 bolts where used till 63 or 64 then they went to 6 bolt and didn't change till the last 302 in 97.