I searched for this but found nothing. The better C4 transmission year starts at 1970? When they talk about case filled vs. pan filled is the 1970 and up case filled and earlier pan filled? What is the weak link besides the planetary gear?
there is a whole lot of incorrect info in that quote Jester, I mean a bunch. You might want to consider taking it down, seriously. The guy that wrote it has a bunch of stuff mixed up. The C5 is not just C4 with parts numbered C5xx... The C5 is a similar design to a C4, but it has a different filter, an additional timing body that bolts to the valvebody, and I think some had lockup converters but I'm not sure of the specifics. No C4's (regular C4 design used until 79 or 80, whenever) had lockup converters. The bellhousing bolts are the front pump bolts on these normal C4's, regardless of 157 or 164 tooth bell, pan fil, case fill , etc. I've never seen or heard of a pan fill C4 unless it was mid to late 70's. If you have a 65 mustang with a pan fill "C5" trans and lockup converter with seperate bell and front pump bolts, I am 100% sure it ain't original.
To answer the original question, pan fill vs case fill doesn't really make any difference with regard to strength, its just an old wives tale. The planetarys aren't so much a "weakpoint", they are pretty tough. I know Performance Automatic sells beefier ones for a fair price, but the stock ones can handle some big power.
Lots of goods tech info can be found at fordmuscle.com, they have a seperate tech forum just for C4 discussion, some really smart guys there that can point you in the right direction. Theres even a 'ultimate C4 build" thread thats about 20 pages long, do a search for it. There are all kinds of oiling mods, roller bearing conversions, drum modifications, etc, neat stuff.
there is a whole lot of incorrect info in that quote Jester, I mean a bunch. You might want to consider taking it down, seriously. The guy that wrote it has a bunch of stuff mixed up.
Thanks for the heads up. I didn’t know much about C4's other than I have one. Sorry for the confusion/ misinformation. But that is why I posted it with the disclaimer.
Thanks again
Jester67