The people on this forum are very knowledgeable,so I thought I'd post here.

I have an F-350 (everything--emblems, registration, etc.--says F-250, but when buying suspension/steering parts, I have to buy F-350 parts or they don't fit) which I am changing the 390/c6 to a inline 300/c6. My question is this: With the C6, is there a difference between the regular one and that used in the trucks?

What do I need to specify when ordering? Numbers?

Thanks for the help! This forum has been a great resource.

 

To answer your question, I don't think there is a difference but unknown for sure. I do think a 390/c6 might not bolt up to a 300 but any SBF c6 would probably bolt up to the 300. You might consider stiffening up the c6 a bit with an upgrade kit for towing. A tranny shop would probably have the details.

 

my thoughts exactly. the FE bolt pattern will not allow you to mate the i6 to this particular c6. craigslist small block (302,351W/C or an i6) c6's in your area or pull one at a junkyard.

the c6 is pretty stout. my brother gave it hell when it was behind his torquey 351W. still works like a champ in my truck .

the i6 will NOT like the c6 with it's thrust washers sapping power (im debating throwing an i6 in my truck or going to get a 351W, huge toss up). you might want to full rollerize the c6 to reduce that 30+hp loss. it will also be stronger since i hear the #9 thust washer is a weak spot. there's alot of talk about it over the internet and maybe in the transmission section of this forum.

i know for a fact this website C6 transmissions and parts has alot of really neat things for the c6 like adding extra friction plates and steel 6 pinion planetarys.

also go get a really low stall converter (i think TCI makes a 1200rpm stall converter)

*EDIT*
re-read the post. all c6 transmissions are the exact same in every car or truck, 2 or 4wd. only difference is the tailshaft, bellhousing bolt pattern and torque converter. all kits, seals and whatnot are the same

 

I have a '75 F-350 which I am modifying quite a bit. It presently has a tired 390 with a C6, and I am changing it to a 300 inline which I hope to get about 250 hp out of.

A few years back I changed the rear end from 374 gears to 331 ratio. I still pulls a loaded trailor with a load in the bed over the mountains into Oregon, albeit at 45 mph, but a trooper nonetheless.

Now that the engine is being assembled, I have to get hot and make up my mind regarding a trans. I know the c6 is bullet proof, but I'm dying to get overdrive.

A c6 with a gear vendor overdrive would be a dream, but the cost is more than a bit steep. I've been reading about beefed up AOD's, and was looking to get some knowledgeable feedback/advice.

I know ford never but an aod in anything heavier than a 1/2 ton, but there are shops that now modify them to go in dragsters.

Let me know what you think.

 

Beefed AOD is $2000+, cheaper than the GV for sure. AOD sites with transmissions, parts and propaganda:

AOD Transmission from PATC, AOD Transmissions

AOD Performance Products - Baumann Electronic Controls

www.CKPerformance.com

TCI - Ford AOD, AODE and 4R70W

TCI has the best as far as listings and prices on transmissions. Note the use of '88-'93 cores due to upgrades by Ford.

The AOD has a lower first than the C6 also.

 

you might want to slam a ZF-5 in there. the AOD seems alright when beefed up and everything is tuned, but it still has a bad reputation when it comes to longevity. i know for a fact the c6 will last about 120k+(living proof), but i have never heard of an AOD lasting nearly that long under a loaded truck. sure you can beef 'em to take a beating but how long can you go without worrying about it? its just me talking but i think the AOD isnt the right choice.

and as ive said earlier which i highly recommend, put E4OD gears into a c6. lower 1st and second with a 1:1 third. raise that rear gear up a lil to lets say 3.25 and you will be cruising 65 at 2218 rpm. get some movement off the line with lower first.

some options
c6/gearvendors- have one it works GREAT with 3.25 rear gears going 65 mph(check junkyards, i found mine there)

AOD- kinda skddish but it has come a long way from being crap (.66 overdrive sounds nice too)

E4OD-tried and proven to be a great transmission, just need a breakout box/EFI

ZF-5-a tank of a manual transmission that comes with a granny low and a.78 overdrive i think.

t-18/19/NP-435-proven to take torque but no overdrive. get a higher rear gear to have highway driveability (3.31 gears and 32 inch tires makes a cruise at 2259 rpm)

if your into slamming gears like i am, get a manual. auto is fine but i wouldnt want to put that AOD under much stress if the TV cable isnt adjusted correctly.