460 Ford Forum banner

C-6 Transmission I.D. and rebuild questions.(maybe sticky?)

167K views 208 replies 45 participants last post by  Jetman 
#1 · (Edited)
this top post will get added to as the more info i come across, with internal mods, part numbers and so on. Enjoy.

long tail , short tail...

where too look up years and what not?

I wanna lay down some base idea's on this transmission and its parts and what we have done too make them work!

I have two different C-6 tranmissions sitting here. One seem to have a longer extension housing, and the odd side mount setup.

Ill post some pics of both tranmission's

transmissions


tails


tail one


tail 2


i just too make sure i can swap internal's and output shaft's and housings

heres a good readup on rollerizing a C-6
http://www.460ford.com/forum/showthread.php?t=105057

and a build up on a Big C-6 with trans brake or manual valve body. (fixxed)
http://www.460ford.com/forum/showthread.php?t=105603

5 clutch drum setup with pics and info (thanks greg)
http://www.460ford.com/forum/showthread.php?t=121505&highlight=clutch+drum+setup

TCI trans brake fix pre frank!
If it's a TCI I have a fix for it as the problem is the 2 checkball slots in the lower half of the valvebody are too large and too long and the checkball cannot find there seats in the spacer plate. there should be 2- 1/4" steel checkball ,one in each slot . you need to fill these slots with JB WEld or another good 2 part epoxy , then using the spacer plate as a pattern mark the 4 checkball seats in the epoxy - using a 9/32" drill bit drill 4 holes in the epoxy approximately 9/32" deep at the 4 marked spots, then using the drillbit router a new checkball slot in the epoxy , make sure the checkballs will roll free from one end to the other in both slots - install the spacerplate and check to make sure the checkballs will roll from one end of the slot to the other and not over shoot there intended seat, the holes in the spacerplate should be 7/32" for the High checkball and 5/32" for the low checkball . In between the lower half of the valvebody and the spacerplate there should be a gasket ,if there is not make one out of .005" gasket material, Torque all Valvebody bolts to 55 inch/lb's
Frank
manual and trans brake for tci info!
Okay now , Who Manual as if it's a Tci for the Manual you need to modify the 2nd gear servo and plug the servo vent and for the TCI brake VB your have to run the servo unmodified and the vent hole open


im putting this here, just incase someone dont click the link and all the info is in one thread!
C6 trans build for transbrake or manual valvebody
This is what I do aC-6 build and it seems to give good durability

- Low /reverse Clutch
- piston use the old style with the 24 return springs and the check ball , locate check ball at 12 o'clock (these springs have a free length of 1.070" as opposed to the high/reverse free length of 1.400"
- fibre's & steels , I prefer red alto's and kolenes but the stock clutches hold up well, If your trans has a waveplate discard it . I like to have a min of 5 fibres and steels set at .060 clearance ( .012 per fibre and steel) . the pressure plate may need a step machined in the out edge twice as thick as the snapring to aid in installation of the snapring, use a magnet base dail indicator mounted to the rear sprag race to check clearance- air check
- rear planetary hub use the one with the 1" long splines Part# for the hub F81Z-7D164-AA
- rear planetary- preferred is a 4 pinion
- Forward clutch - prefer red alto's and kolenes,and use the new style drum (new style has a wave plate, 5 & 5 here plus the wave plate .040-.050 clearance, the pressure may need a step machined in it for the snapring or you can use a second internal pressure plate as the outer , make sure you have the right forward ringgear assemble . the new style drum has a .400 deep torrington pocket were as the old style only had a .330 deep pocket and the ringgear asembles are different the new style has longer splines on the outside and the hub is different also. a missmatch of parts here will raise havoc with end play , the planetary's are the same 3 pinion, the reason for using the wave in the forward is that with racing line pressures and no waveplate it tends to snap the end of the drum off at the snapring groove after a period of time .In my max effort trannies I leave out the wave and contend with the drum breaking if and when it happens , ussally I just put an new drum in each year

2nd gear - "R" servo and an "E" lever and the toughest spring I have , Band I been getting good service out of the 2 1/2 " flex band kevlar lined

- High/reverse drum , 5 clutch drum preferred, but the stock 3 clutch drum can give good service if modified by cutting a new snap ring groove . there is 2 alternatives here depending on which drum you have as some drums have a longer spline than others the ones with the long spline an new 1/8" groove is to be machined in the drum at .565 from the bottom of the original to the top of the new groove this will allow you to use one of the stock selective snap rings to achieve a clearance of of .012 - .013 per fibre & steel and using alto pt# 026757HP kit you can install 6 fibre's and 6 steels witha clearance of .072-.078 (note Alto's recommended clearance with this kit is way to tight) with the shorter splined drum you machine a new snap ring 11/8" groove in at .400 up from 5the bottom of the original groove to the top of the new groove and then step cut the pressure plate approx .165 " to allow snap ring installation and removal. With this mod the drum will hold 5 x 5 standard red alto's and kolene steels . another drum mod to do is drill a series of 1/8" holes into the perimeter of the drum in a zig-zag pattern were the steels engage in the drum , this ads in letting the oil out of the drum a cools the clutches by letting more oil flow through between the clutches , also fill all spring pockets in the piston with springs.
-pump sealing rings , get and use teflon sealing rings as they last a lot longer than the cast rings and they do not wear the drum
- set trans end play at .020-.045"
- and adjust the band , tighten to 120 inlbs and back of 1 1/2 turns and tighten lock nut


any Questions email me at fmerkl@eidnet.org or call 403-793-5412




so how do we id them? so i can clean them off and check?

are there any case mods? I plan on doing this over winter. so i can be ready come next year! i do have a c-4 sitting here and the input adapter. but its seems it take a lot more money to build the c-4 too take the abuse i wanna put thru it. and the internals seem to be smaller and light, but just dont look as strong!IMO.

reading will best serve you here. clicking the links and reading this thread can help on tons of stuff.
 
See less See more
4
#27 ·
Ditch Baby said:
im going to throw my noob question in here....



Got a '79 F150 with the C6... i want it to handle some good power and abuse. I want to get the motor rebuilt to around 500hp/700ft lbs at the MOST... thats if i feel like getting frisky, but i bet it will be more around the 400hp/600ft lbs

What do you do to these trannies to beef them up?? Ive seen re-build kits out there but come up short when looking around for kits to beef these things up.


and what makes a beefy tranny beefy???
follow the links i have posted in this thread. i think they are in the top post! even stock, your c-6 will handle what your going to throw at it!
 
#29 ·
Frank Merkl said:
You have the Beef!, "79 F150 460 auto ,one of the fastest trucks ever produced. Had a customer back in '79 bought a new F150 Lariet,on the" PDI " I change the lower crank sprocket , he drove it to the race track with 200 miles on it and it ran 13.60's with a set of used oval track tires
Frank

I should have stated its 4wd with 38.5 TSLs on it hahaha.


Ill keep searching i found much info after i posted that
 
#30 ·
hi there
i have a lincoln /460 c6 and a fe 428 c6 can i swap the tail shafts over?
thay look close but i dont want to strip then down and find thay dont fit many thanks...460 and c6 to go in my 94 mustang soon....
 
#33 ·
Re: c6 manual

In4x4guy said:
what is the best assembly/modification manual for the C6? thanks
im using a plain jane rebuild manual ! i have the motor books and some other reference books . im going with franks build up cause it has proven itself! i did a plain rebuild on a sb c-6 back in trans class at northwestern and it worked great! so im hoping to have this done by summer.(if funds allow it) but with my sons custody case still being ongoing, my attorny is sucking up alot of my race car funds!
 
#34 ·
Gearhead way to go ! send me the C8AP/C7AP Valvebody I'll build you a trans brake Vb and put it on the shelf until you can afford it
PS I'll monitor this thread ,so if anybody has any C6 questions I'll answer then here
Frank
and If you have any Questions that need a quick answer or are having trouble assembling your C6 just call me at 403-793-5412 between 8am&11pm MST I'd like to leave the PG's for the Bowtie Boys!
 
#37 ·
Re C6 rebuild

Hi Frank just reading this post. I have a Lincoln C6 long tailshaft core in the garage , was your reason for not using the long tailshaft just because of the mount as I plan to use a mid plate to mount with the motor plate? Also I was trying to decide on saving the money for a PA sc C4 trans instead of using the C6 but I'm still up in the air on it due to funds etc. I'm trying to map this build out and put a little into at a time as I'm in the same boat as Gearhead with custody issues. I'm just tired of seeing the car sit in my garage and not doing anything to it. I have 0 experience with trans rebuilds but if it can be done with a manual and your guy's great help , I'm not afraid to try. I'm building a fox stang with the usual stroker BBF 9 in , ladderbars , 28 x 13 Firestones. I know the car will weight less than 3000lbs. I'm hoping to eventually run solidly into the 9s maybe faster as the budget allows. Do you think I should take on the C6 build up?
 
#38 ·
forget the pa super comp trans. it cost 2000 dollars. plus a 300-400 bell. and a c-4 converter. you can use the c-6 converter with a c-4(i have the pa adapter) but ill have around 1000 or so in this c-6 using stock parts. roller bearings cost me under 40 bucks. the heavy duty rear hub is 30. clutchs and steels around 250-300. seals gaskets etc 40-50. and one of franks valve bodys.(which i need to make sure is the correct one!! :cry: ) only thing i need now is the machine work done and im figuring that should be no more then 100! plus if you rollerize it franks way, its full roller. the pa super comp is not! it only has 4-5 rollers in it! and a good c-4 will need all 12 in it to hold up to what i plan on doing. id rather refresh every winter then rebuild and replace parts in a c-4 after a few pass's and street abuse! i already have a billet c-6 converter with plate, 4800 stall! and my c-6 has the deep tci pan already. which is only about 130 or so depending on where you get one. and maybe before i build my turbo terror 385,ill upgrade to the hardened input shaft and billet front drum! which im sure the c-4 wont hold up to!
 
#39 ·
Frank Merkl said:
Gearhead way to go ! send me the C8AP/C7AP Valvebody I'll build you a trans brake Vb and put it on the shelf until you can afford it
PS I'll monitor this thread ,so if anybody has any C6 questions I'll answer then here
Frank
and If you have any Questions that need a quick answer or are having trouble assembling your C6 just call me at 403-793-5412 between 8am&11pm MST I'd like to leave the PG's for the Bowtie Boys!

well frank then heres my question to make sure i have the correct one! on the filetr side i have three that start off with the c8 numbers. but on the valving side they are d2 numbers. im thinking these are not what you need, but it doesnt hurt to ask at this point. and if you can do that for me , id love you forever!

p.s i new this thread was worth the effort !
 
#41 ·
Gearhead , I can make a transbrake out of the D2AP upper/C7AP lower it's just that you will have to be super careful on postioning the valvebody in the case ( not that hard ) When I find my pic's in my computer of the proper way to check clutch pack clearances using a magnetic base dial indicator I post them
Frank
 
#43 ·
Gearhead, Ship valvebodiesto me at
Frank Merkl
Box 493
Brooks , Alberta
T1R1B5

Ship using USPS parcel post
make sure wrap the Vb in a couple of rags, (post office doesn't like any oil leaking from packages)double bag in ziplocks and put it in a strong cardboard box
Frank
 
#49 ·
Okay Guy's finally got around to posting pic's of how to check clutch pack clearances

Checking low/reverse min .060 with 5 clutches max.080

Checking High/reverse .012-.014 per clutch and steel ie;5clutches .060-.070 , checking using stator support to pressure check

forward clutch ,checking using stator support for pressure checking .040-.050 with 4 clutches and wave installed or .050-.060 5 clutches and NO wave plate

Checking for clearance on the high/reverse clutch pack for the forward drum there must be clearance at the x for the forward drum , CJ drum shown that has had a new snapring groove so it will hold 6 standard clutches and steels, pressure plate has been step cut for clearance, notice identification groove in drive lugs

checking stack height on forward planetary for forward drum , on a drum with .330 pocket measurement should be .335-.345. on a newwer .400 pocket drum .405-.415

new style .400 pocket left, right old style .330 pocket stack height notice ident ridge at X
Frank
if I have you totally confused just call me 403-793-5412
 
#50 ·
I guess I should add when using the stator support for pressure checking clearances use your old cast sealing rings and when you assemble the trans using teflon sealing rings pack the sealing ring grooves first with Vasoline then put the teflons in the grooves as in will hold the teflons in the bottom of the groove . Also if you are just using a shift kit in your C6 Don't use the teflon sealing rings use the stock cast ones as most shift kits don't bump the line pressure up enough to warrent using them. also after you have the trans assembled and before you put the valvebody on ,pressure check the trans to make sure all the clutches apply and with the teflon's you will have to fill the ports with trans fluid several times and air check to hear them apply . PS ,Vasoline is the best assemble lube for a trans -use it on the seals when installing the pistons in the drums and the case -for holding the torringtons and thrust washers in place on assemble
Frank
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top