C6 Rebuild Questions-Newbie

[HarleyJack17]

I finally started on rebuilding my C6 to go behind the 445.  I have not posted much, if at all here (mainly on the other forum before the change) but had a few questions for those that have re-built their own transmissions.  What I am curious about is upgrades and differences.

By upgrades, would going to 4 pinion planetary be a "needed" move, along with sourcing an older longer splined rear hub.  I purchased Ken Collins C6 rebuild dvd for some preliminary info and he mentions some of this. Simply put, what would you do and not do?  I am not afraid to spend the funds if needed but would like to keep the budget at a minimum with the goal being reliability over heavily modified for all out performance.

Also, I am looking at the Broader Performance 500 HP rebuild kit and curious if anyone here has used it and can detail what exactly is different from a master rebuild kit? From what I read it allows stacking more clutches, servo, and shifting mods. Also curious if this kit or any, come with any of the bushings(not the thrust washers).  I am completely new at it but not afraid to try.

I have it mostly torn down and should finish in the next day or two to start inspecting parts for wear. So far no real concerning sights but I have yet to open the pump up or separate the drive groups.  Again, nothing looks too bad so far other than it being real nasty in the pan/fluid but there is still a lot to inspect.

The engine is my 445 that dyno'd at 487 HP /547 TQ.  All going in my '75 F250 4x4 and use will be a driver/occasional romp on it type of deal.  Plan is to go up to 38" tires from 35's but no bigger and keep the 4.10 ratio.  So it's big, heavy, and running around a 3.60 final drive after larger tires.     

Thanks for the input.

[cammerfe]

FWIW, my own approach has always been to over-build. Having it but not needing it is much better than the other alternative---within reason. (I've decided not to put ultra-trick coated wristpins in my next engine build for instance. Maybe the next one after that. )

If you over-do so that a component fails, there's a chance to 'lunch' the whole works and have to start over. If you have a bit more than you actually need, you simply continue down the road and arrive at your destination.

Seems to me to be a good way of doing things.

KS

[Drew Pojedinec]

I'm sure folks are tired of seeing this link.... but this was the build that is in my car.

https://www.facebook.com/pg/AirFuelSParkTech/photos/?tab=album&album_id=174252049980201

Scroll through the pictures as there is info in there.
Good luck

[HarleyJack17]

Cammer, I tend to agree with your input but it is easy to spend a fortune on this quick and that point it would likely be more wise to buy a buikt unit with some form of warranty. Not looking to spend quite that amount of cheddar unless the fortune cookie says “you will be sorry for being a cheap a@@“ 
Drew; I saw your post on here(while back) and tried to look through it but had issues with pics...may have been my pc.. I will check out the FB link.  I actually bought Kens Dvd based on your input on that thread and am happy with it, though I plan to get a manual prior to assembly/parts purchase. The trans is pretty straight forward just A LOT of moving parts. Thanks for the input guys and look forward to more info.

[Drew Pojedinec]

Yeah, photobucket killed links of images so I moved all of it to my FB page so I could share.  Either way, good luck, and lotsa folks here have an absolute ton of experience with c6's, so if ya hit a dead end be sure to ask the forum brains.

[GJCAT427]

I have rebuilt 2 C6's over the yrs. One stock and a modified for my 56 F100. It was fairly straight forward and the best advice I can offer is KEEP IT CLEAN! One of the dirtballs I had working for me looked at what I was doing and for some stupid reason left part of the assy uncovered, I was gone for the day when he did this, then started grinding nearby on a job. I came in the next day to find grinding particles in the case. Talk about pissed off. I had to disassemble the tranny and start over. He was terminated to say the least. My tranny in the 56 was built to handle HP& torque. A local buddy who worked at the local  Ford dealer rebuilt it and gave me a list of OEM oarts to get. That build was Quite amazing. It held up to a 428CJ and then to a 427. Never a bit of trouble except for a bad tranny cooler line which was caught before any damage occurred. I retired it 10 yrs ago in favor of a toploader.

[fryedaddy]

i changed out my toploader 32 years ago,put in a c6 in my 428 comet.for the last 10 or 15 years i have been waiting on that c6 to tear up so i can put the toploader back in.it looks like its going to last forever.i dont want to do the swap till it tears up but it has done great for 32 years now.if they are done right it looks like the c6 is a tough trans!

[e philpott]

Broader prefers 3 planetary over 4 gears just based on rotational weight , both work fine and more than adequate

[HarleyJack17]

This is the first transmission I have ever been into.  I definitely can see the importance of keeping it "lab clean".  A lot of fluid paths and working parts.  Almost amazing how they work as well as they do.  I am really surprised this one was working as good as it was prior to tear down. It was filthy outside and inside the pan but so far I have not seen any major damage.

Mr. Philpott, your comment on the gears is the input I was looking for...at the power level I am at, and intended use, what is sufficient vs. overkill/$$$.  That is good info.

I guess my final thing to ponder is where or not to replace the thrust washers with "rollers" when/where I can without having to buy expensive new part sets/machining.

Thanks again

[Drew Pojedinec]

Just do a #9 roller

[Falcon67]

Agree - at least the #9 roller.  I have a roller C4 and it does require several machining steps.  Unless you are hammering on it constantly - like I do - regular thrust washers work just fine.  You will want to increase clutch apply area (more plates & disks) in any build if you can.  Not that familiar with the C6 but if the power flow is like the C4, your two things are 2nd gear servo apply and high gear clutches.  In the C4 and C6 as far as I know, low/rev (forward) clutch is applied in all forward gears.  2nd is intermediate band apply, 3rd is band release/high (direct) clutch apply.  That's where everyone fusses about "flare" - the transition time between band release and high clutch coming in.

And yes, as my friend way back that was a master Ford mechanic said "Just put it back together the way it came apart and it'll be fine".  That said, power train end play and clutch clearances are critical to proper performance.  Look into air checks for clutch actuation tests prior to final assembly.

[Falcon67]

Example using a C4 -
Direct clutch air check with clearance


Forward

[gt350hr]

  I just finished a C6 for myself. Changed to all needle bearing , wide ratio , 5 clutch (CJ) high drum , kevlar band , aftermarket "R" servo , minimum spec end play etc. It was a pretty easy conversion and is MUCH easier to turn now. The low gear kit may be overkill but I bought the stuff in a "lot" buy of Ford Motorsport stuff years ago from a local Ford dealer getting out of racing parts sales.
     I have several NOS Ford Motorsport parts I will post ( for cheap) in the classifieds.
   Randy

[HarleyJack17]

I finished the main tear down of the transmission last night. Anyone here know if the C6 for an F250 4x4 is different that the extended tail shaft version for 4x2 trucks/cars?
I ask because on the last drive hub, after removing the final planetary my info shows a snap ring holding the rear drive hub in(basically retaining the output shaft). That snap ring was not present. So after removing the planetary, hub, clutch snap ring and clutches I could, and did remove the output shaft and rear housing.  I do not see what looks to be a snap ring groove in the output shaft either, at least not a square cut groove, maybe what I would call a tapered grove..nothing looks damaged there.  The transmission has been into based on the marks in the case portion that retains the parking pawl thrust washer.

I did find it intriguing that the rear of the output shaft is supported by a large caged roller bearing. I suspected a bushing.  Anyway, I figured I would ask.   

[Drew Pojedinec]

That bearing has a retaining ring holding in the bearing.  Remove the gov and everything else in the way and it's easier to get to.

That style tailshaft is valuable to some off roading types.

The tailshaft and output shafts of c6's should be kept together and no problems will ensue.