the curse of the blown transmissions strikes again

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72HCODE

"My World is Fire and Blood"
Joined
Jul 4, 2010
Messages
3,091
Reaction score
56
Location
New York
My Car
71 Mach 1.
Well my C6 went down this Saturday.

did a hard acceleration and the kick down stopped working.

1st gear went out and trans will not go into 3rd.

the trans locked into 2nd gear and began slipping.

if i put the trans in 1st manually the entire drive line locks up, throw it in second and transmission works but you can feel the clutch packs slipping and occasionally you can feel the trans slide into 3rd gear and slam you forward then it slips back into 2nd gear.

limped home, and checked trans fluid which is now full of black clutch pack material...

Fantastic.. no idea what happened or what broke. no loud noises or anything.

now i have to drop the pan and see what i can see and most likely pull the entire engine and transmission out the car to even start to diagnose what happened.

urg....

 
Bummer. Very sorry to hear your bad news. I had a C4 rebuilt at a local tranny shop for about $700, that included a kickdown setup which (I think) was about $130.

When I drive my car I sometimes feel like I'm going to break something. I call it the "driving a 40 year old car anxiety". Wonder if anyone else feels the same way. Good luck. I'm sure you'll be back on the road soon.

 
Sorry to hear about your C6. At least you didn't have to drive home in reverse!

My C4 is starting to slip in Drive when it warms up and won't go when starting from a stop. If I pull the gear shift into 2nd or 1st it works fine. Just an occasional problem, but I try not to drive too far from home.

 
My C4 makes me nervous every time I am out in the mustang. I have it built pretty darn stout. Broader valve body, Kevlar clutches, 3000 stall converter, B&M ratchet shift, ect. BUT when you stomp on the gas with close to 600HP , it makes ya really nervous about the C4!! I never thought I would be throwing that kind of horsepower at it when I built it 7 years ago! But it keeps on keeping on! LOL :D Once it finally does grenade I will be putting in an auto with OD or a 5/6speed manual.

Good luck with your C6, all the ones I have had over the years were damn near bulletproof. On the bright side if you stay with the C6 they can be rebuilt pretty damn cheap.

 
72HCode,

Sorry to hear about your misfortune with your trans. If you need a rebuildable replacement, I just so happen to have two available. One was out of my car with 100k and the other was from a low mileage take-out many years ago. They both are complete & have converters. They are yours for the taking, just come & pick them up.

I am located in Nortwest NJ near the NY / Pa / NJ border.

Let me know.

Thanks, Jay

 
Hey jay i may have to take you up on that.

I'm exploring some options, have not made any headway into the car itself.

i don't have a truck have to think about how i would go about picking one up.

its like hey blew the trans get to put the car away for a while and go back to work and other life issues HA.

I'll drop you a PM also.

------------------

i noticed some funny behavior from my c6 last year and i think once this year, where i would drive, come to a stop while making a turn and when i started to go i swore i felt the trans not engage for a spit second.

I'm sure this problem was present before and me stomping on the trans just made the problem finally manifest itself.

meh i'm kinda glad it happened to be honest just wish it was a faster easier repair.

72HCode,

Sorry to hear about your misfortune with your trans. If you need a rebuildable replacement, I just so happen to have two available. One was out of my car with 100k and the other was from a low mileage take-out many years ago. They both are complete & have converters. They are yours for the taking, just come & pick them up.

I am located in Nortwest NJ near the NY / Pa / NJ border.

Let me know.

Thanks, Jay
 
72HCode,

Sorry to hear about your misfortune with your trans. If you need a rebuildable replacement, I just so happen to have two available. One was out of my car with 100k and the other was from a low mileage take-out many years ago. They both are complete & have converters. They are yours for the taking, just come & pick them up.

I am located in Nortwest NJ near the NY / Pa / NJ border.

Let me know.

Thanks, Jay
Wow. Very nice of you to offer your parts to help!

-And you guys are in the same part of the country.

Very cool.

Ray

 
based on the location he would be about 120-130 miles away from me.

 
i don't have a truck have to think about how i would go about picking one up.
Simple, take the wife's car.

Put some cardboard down in the trunk.

Used transmissions never leak, you'll be OK...

Don't forget to pick up a gallon of milk before you get home.

And flowers.

You may need those.

:D

 
Last edited by a moderator:
sorry to hear this!!!

sort of a bad year for transmissions...several threads already with guys that have busted up trans...included myself!!!

I installed my C4 yesterday...but noticed my engine mounts cracked...both of them!!! guess what now...I just decided to remove the whole dang motor!!!

oh well...like they say..its a 40yr old money and labor pit for me.

 
I call it the "driving a 40 year old car anxiety". Wonder if anyone else feels the same way.
Oh yeah - been there, done that. My T-176 4-speed locked up in my Jeep... at speed of 70mph. It actually split the case down the middle. I had to find a new case, a new countershaft gear, both of which are more rare than hen's teeth, then rebuild the dang thing. Every time I drive the Jeep down the freeway, I keep waiting for the transmission to do the same thing it did the day it blew up on me.

Imagine my fear when after I installed the new rear axle with a Detroit locker. The first time it clicked and Popped (more like "POW!") going around a corner, I thought the Jeep was done for sure. ;) :D

Hang in there, Dan. It'll be OK.

 
you know what is scary:

Learning about all the different variations of C6 transmission from 1966 till 1996.

like here is a little tidbit i didn't know.... apparently after 1976 ford changed from type F to Dexron.

So if your running Type F in a C6 after the make of 1976 you could be setting yourself up for major issues down the road with the clutches.

So my current trans is a late 70s C6 from a bronco truck and i filled it with Type F when i should of used dextron.

the slicktion material is different and that is why they make 2 different master rebuild kits with different bands and clutches.

and you have to watch out for kits that claim 1966-up or 1966 to 1996 master kits, then there are the more proper 1966 kits, and 1967 to 1976 kits

and i'm building up a trans decoder list for 71-73 mustangs and holy cow is it difficult. there are different lists on the net and most do not correlate with each other.

ARUGH

 
you know what is scary:

Learning about all the different variations of C6 transmission from 1966 till 1996.

like here is a little tidbit i didn't know.... apparently after 1976 ford changed from type F to Dexron.

So if your running Type F in a C6 after the make of 1976 you could be setting yourself up for major issues down the road with the clutches.

So my current trans is a late 70s C6 from a bronco truck and i filled it with Type F when i should of used dextron.

the slicktion material is different and that is why they make 2 different master rebuild kits with different bands and clutches.

and you have to watch out for kits that claim 1966-up or 1966 to 1996 master kits, then there are the more proper 1966 kits, and 1967 to 1976 kits

and i'm building up a trans decoder list for 71-73 mustangs and holy cow is it difficult. there are different lists on the net and most do not correlate with each other.

ARUGH

The C6 was and is a very stout transmission. Good and bad. Good in that it was so strong and dependable. Bad?! because it was so stout that it was used in MANY applications up to and including F-600 trucks and "Toters" with C6's used to move F-16s at the Base. There the confusion starts. With so many applications of use, the correct repair parts became difficult to figure out. Even at the dealership level we often had difficulty with before and after production dates and if the trans already been repaired and had the new clutches with required Dexron fluid. Ford did have two different rebuild kits but replaced them with one that had a label/sticker to place on the trans dipstick handle to alert the tech on the proper fluid usage. Of course you know what happened to a lot of those along with carb, disb, and differential tags. I doubt that many pre 1976 C6's exist today that have not been repaired in one form or another, so I would use Dexron fluid if in doubt.

 
My FMX is with Ford tech. He said not enough metal in pan to have any hard part damage. Looked at CJ Pony for OH kit but does not look complete. No modulator or filter no band either. Any know where to get a master OH kit for FMX?

Alan L

 
it is kind of the same with the C6 you can get a kind of complete master kit but there are still a couple of things missing.

I'm slowly researching what i need.

i have a line on a 1972 C6 from a Qcode.

I want to thank jay (clevelandcoupe) again.

Should have more information over the weekend or into next week. Cross fingers no Jinx.

 
update to the learning curve.

I've learned there is a massive difference between what is posted online about master rebuild kits.

and what should actually be done during a rebuild.

the master kits they sell online for 150-230$ are basically new seals. there is a bushing kit required as well and the question of whom do you buy the kit from, plus the installation of all these new bushings.

for the most part just about every video or DYI guide online covers the master rebuild kits which again are just seals with the assumption that everything inside the transmission is rosey and perfect.

many books don't even cover everything, of the 3 books i bought all pretty much cover just using a master kit for rebuilds.

i think many people have thought that must be it, buy a rebuild it, take it apart according to the instructions and throw it all back together with new seals and clutches and you are good to go.

but i can see this covers 40-50% of a real transmission rebuild. only a couple of videos i have on c6 rebuilds have even talked about checking the various internal parts for wear or even how to do it, none talk about how to go about replacing some of the parts just that a part did not meet toleration or is worn.

thankfully one video i found talked about when doing a transmission rebuild you need a complete bushing kit and all bushings should be replaced during the process. i researched c6 bushing kits and i have to say it is REALLY confusing as well.

from the looks of it. if you have no wear inside a trans then you use a c6 master kit. but you are suppose to have a master bushing kit as well. additionally you could be replacing more and more metal parts as you go deeper into the trans towards the yoke this is due to the weight of the driveshaft and power output causing the internals to sag into the bottom of the transmission case.

surprisingly when you look over a diagram of a c6 transmission you expect a good amount of parts inside until you watch a detailed video of taking one apart completely and properly and Holy cow its like a clown car you start wondering how on earth they crammed so many things inside such a tiny case.

i can see that the amount of work i thought going into rebuilding a trans above what an average trans shop would do is at least double.

I can also see the pit falls and a bunch of ways compromising on cost with a rebuild will bite you in the butt again.

So far as a novice i can pretty much take a trans apart layout the parts and know what they are kind of, and i can diagnose what would of failed inside the case or what parts need to be replaced but that is about it. I have many more books and videos to watch and it isn't as easy as i hopped.

I can see from the videos and books i read pretty much what i would expect to find if i opened my blown trans.

first i would expect to see the bottom of the fluid pan filled with clutch junk, a black layer of shmoots and red fluid on top.

as i took things apart the pump at the front would be ok, the first set of bands 3rd and reverse would be in good shape, this is because my reverse still works. so that clutch drum assembly and the front pump would be cool with just a c6 rebuild kit.

then the fun starts.

the forward clutch would be burned up and fused together.

forward ring gear would be stuck in the clutches.

2nd gear band i'm sure would be toast because i'm betting the trans shop that screwed me 7 years ago never replaced it.

forward planet assembly, i will bet these will have mechanical damage, either caused by being worn out or something else wedged into the gears even some clutch junk could of gotten into them.... it seams most crap transmission shops don't even know how to inspect these.

there are about 3 bushing at this point that need to be replaced as well.

sun gear shell would be ok,, but its got 2 bushings in it.

rear planetary gear assembly would also be in question. Some trans shops don't even go this far as most rebuild kits stop here with parts in the kit. they usually change the rear seal for the yoke and just throw everything back together but that is where the real wear and tear damage starts because of gravity load on the back of the trans.

rear ring gear assembly is usually ok but again another bushing needs to be replaced inside.

then you have low and reverse clutch assembly which some trans shops don't even touch they just assume they are ok, the master kits do include these bands and clutches. these control the reverse gear so unless you tell the trans shop my reverse isn't working they don't bother going inside.

then you get to the inner race for low reverse which is usually toast.

so now i get why they will either swap a trans or why a fluid flush is a bad idea.

well one step at a time...

 
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