C-6 Toughness?

Last night my C-6 gave up on me, I had to settle for second place. I bought this truck (1977 F-150 4X4) 4 years ago and the C-6 was in it, all I did is put a shift kit in it and abused the crap out of it. I have put 550-700 hp (apx) thru it with 3 different engines, this was Mud and Dirt drags, I feel that I got a great life out of it for a stock transmission.
I don't know what went wrong with it, other than the smell of burnt fluid in the air, the first sign of trouble was it locking up while moving, like you put the brakes on, then when I put it in gear, it acted like I had a trans brake on.
I don't know what broke, but I have read some posts that have put the C-6 down, so I thought I would post this to say, that I think the C-6 is a tough unit.

gotta figure out what failed and then why. After these are established we can repair the damage and correct the problem. Sounds like some sort of contamination made its way into the vb and then the gears went away as a result. Again need to find the culprit and then make changes and repairs. These are damn tough units when set up correctly.

Well who all showed up last night and how did they do. Were you able to run most of the night? I assume you done pretty good to get second. You gonna get another transmission or are you done for the year?

Well who all showed up last night and how did they do. Were you able to run most of the night? I assume you done pretty good to get second. You gonna get another transmission or are you done for the year?

I am done for the year, my starter caught on fire also. :roll:
Two Chevies showed up from your area, one of them finished 3rd, a 521 Nitros ranger took 1st with one loss. I got a chance to line up beside both of them, and beat them. I told you in a earlier post that we would make the Chevy's feel at home. :)
I was undeafeted on the bubble when I had to with draw.
The next race is Sept. 29th, a day race starting at 1:00. If you and Larry come down I will come to the track and meet you guys. The two guys in the Chevies seem to be real nice guys, even though I told them the wrong higway and cost them about 150 miles. :oops:

gotta figure out what failed and then why. After these are established we can repair the damage and correct the problem. Sounds like some sort of contamination made its way into the vb and then the gears went away as a result. Again need to find the culprit and then make changes and repairs. These are damn tough units when set up correctly.


Jon,
I will have to put another stock one in and hope for the best next year, my very small cash flow is going toward a 547, then maybe get some mods. done to the trans. :)

Did larry come down? How did he do and what were the two chevys that came? I am glad you beat the Chevys thats all that matters. To bad your done will you come watch me run if I go race down there the 29th? Maybe Larry will go with us. And a few others.

Did larry come down? How did he do and what were the two chevys that came? I am glad you beat the Chevys thats all that matters. To bad your done will you come watch me run if I go race down there the 29th? Maybe Larry will go with us. And a few others.

Larry didn't make it, he had to work to late. I can't remember the drivers names, but the guy that pulled one of the trucks there was Scott.
If you guys come down, and I am not working, I will be there for sure.
Also, your class should run 1st that day (1:pm) because it ran 3rd last night, they alternate the classes every race.(that was because the 2 Chevies were running late, I have already explained that one. :roll: )
Bring as many trucks as you can.

The hard parts in the C6 are VERY strong, I think that nearly all C6 problems stem from the valve body/shift timing. We've been working on transmissions for Noelke's monster truck because Matt doesn't want to build any transmissions any more. We've had some of them apart and it's amazing how "stock" they really are inside. All hard parts are stock except for roller thrust bearings in the planetary area and a super strong band, billet servo and arm.

I think the only hard parts that Doug's ever broken have been an input shaft and one set of planetary gears. I was surprised to find also that the transmission has a 4 gear low gear planetary set but a 3 gear on the 2nd gear/front planetary, amazingly strong.

I too have had great luck with the C-6s in my pulling trucks. Although I never did shift them I have gotten better than 2 seasons of pulling out of one without issue and removed it still in good condition when I went to a stick. All that at well over 800 horses. My previous truck had one that lasted for several seasons and still worked good when removed with 700+ horse. I think they are very tough, especially considering that I built them both and I'm no automotive transmission man.

In that same time I've seen a lot of professionally built Turbo 350s and 400s come and go repeatedly, with mine always still going strong.

Later, Bret

Thanks Bret, anyone that knows you will realize what a great trans. the C-6 is. 8)
Next year I will again have to run another stock one, I can't afford to build an engine and a trans., I will see how it does with more Cubes.

Also, I will have to run Iron again, I wish I could afford the work that you have in yours, I am going to have them fully ported, but the floor filling is out of range. :roll:

I had a c-6 with a shift kit, go out on me, on my way home from work. I was doing 55 down the road and all my forward gears went at the same time. All I could do was coast. After I came to a stop I tried reverse, and that still worked. I was almost home, so I finished my trip in reverse. :lol: That was fun. :lol:

Jeremy , you broke the snap ring groove off the forward drum
Frank

So are you guys not using aftermarket performance parts in your C-6s?

If so, which aftermarket performance parts are necessary for the C-6?

I'm not, only due to the expense of them. (shift kit only)

I hope to in the future.

All my tranny's I've built all use stock internal parts , just good clutches and steels ( red alto's &kolene steels & 2 1'2" band) The valvebody is the key on making a C6 live ( which took about 10yrs of R&D to get right) an aftermarket imputshaft isn't really needed until you making over 800ft/lbs torque,and the stock forward drum (snap ring groove breaking off ) if the drum is magged for cracks every 200-300 runs never ussally never gives to much problem . mind you I magged 20 used stock drums last winter on found over 1/2 of them had the start of cracks in the snap ring groove ,that why I got some 4140 billet drums made as an option for my tranny builds and still with a 300 M imput and a billet 4140 forward drum still only put the price at $3000 compared to $4800 Racing 2Speeds. and mine seem to live quit comfortably running mid 7 sec 1/4 mile passes at 180mph
Frank

the transmission that went out on me, was bought through a high performance parts dealer. I cant remember where he got it from.
I had to turn my old one in for core charge. It was about 10 years ago when my C-6 took a dump.

Frank, how parasitic do you believe one of these C-6 transmissions are compared to a racing C-4? Or how much horsepower do you think the C-6 consumes?

Here's another question, if a guy were to only use first gear and never need any other gear... is there a way to lighten/remove a lot of the other internals as to allow for less parasitic loss?

Thanks, Bret

P.S. Shoot me an email with your phone number please.

with all the rollerizing I think the differences would be minimal. The c4 still has a lighter recip assy which is going to be better in a drag race aspect, how much difference is hard to say.

Pretty much need all that stuff for 1st gear, one could put a minimal amount of clutch in the direct and set the clearance loose, lose the int band, I'm sure there are some other tricks one could do as well to get it there.

Bret , if your only using 1st gear -rollerizing the C6 would be the only way to go and if you set the clutch clearances to my spec on my build the drang from the band and the high/reverse clutch would be minimal
Frank
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