Enlighten me, please. I love learning this stuff....
I know the generals, but specifics are nice to know. thx
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oil coolers in PTO boss area
- Thread starter malibu795
- Start date
Enlighten me, please. I love learning this stuff....
I know the generals, but specifics are nice to know. thx
Enlighten me, please. I love learning this stuff....
I know the generals, but specifics are nice to know. thx
Well first of all the C3 clutch is only loaded to 40% when applied so we know that doesn't hurt it. Problem is it is pulsed on for 3rd gear ( slipped ) which initiates a heat cycle. ( clutch got hot because it was slipped on ) Next the C3 is released for 4th gear by being pulsed off. (another slip and another heat cycle ) We are starting to get the C3 real hot now. Along come 5th gear and the C3 is pulsed on again ( slipped ) Another heat cycle. We now have an even hotter C3 clutch pack. While all this took place the only cooling that the C3 got was from the .047 hole in the rubber molded apply piston during apply and it was not nearly enough. now we get into line again at the drag strip to do it again with a pretty hot C3 clutch pack. What do you think will happen after numerous passes?
The TCM comes into play here as well because we cannot adjust shift timing to make it quicker so defuel plays a big part in this scheme. Defuel is needed to give the Alil ebough time to release a clutch before the applying clutch takes hold. Defuel sometimes is not enough with the power levels we are at today. So we get into a tie up ( incoming clutch might come on too fast while the off going clutch could not get out of the way fast enough and for a miilisecond we were in two gears at once.) Example; 7 thousand lb truck at say 600 hp, pedal to the metal, and the shift was not perfect. You get the idea. We have two pressure regulators in the A and B trim solenoids, one is applying a clutch while the other is releasing a clutch during a shif. The TCM must handle this chore and it cant. Now you know how it works.
Well first of all the C3 clutch is only loaded to 40% when applied so we know that doesn't hurt it. Problem is it is pulsed on for 3rd gear ( slipped ) which initiates a heat cycle. ( clutch got hot because it was slipped on ) Next the C3 is released for 4th gear by being pulsed off. (another slip and another heat cycle ) We are starting to get the C3 real hot now. Along come 5th gear and the C3 is pulsed on again ( slipped ) Another heat cycle. We now have an even hotter C3 clutch pack. While all this took place the only cooling that the C3 got was from the .047 hole in the rubber molded apply piston during apply and it was not nearly enough. now we get into line again at the drag strip to do it again with a pretty hot C3 clutch pack. What do you think will happen after numerous passes?
The TCM comes into play here as well because we cannot adjust shift timing to make it quicker so defuel plays a big part in this scheme. Defuel is needed to give the Alil ebough time to release a clutch before the applying clutch takes hold. Defuel sometimes is not enough with the power levels we are at today. So we get into a tie up ( incoming clutch might come on too fast while the off going clutch could not get out of the way fast enough and for a miilisecond we were in two gears at once.) Example; 7 thousand lb truck at say 600 hp, pedal to the metal, and the shift was not perfect. You get the idea. We have two pressure regulators in the A and B trim solenoids, one is applying a clutch while the other is releasing a clutch during a shif. The TCM must handle this chore and it cant. Now you know how it works.
i could read this kind of stuff all day mike :hug:thanks for the sweet info i love learning more about our transmissions
I know kind of funny I would rather learn about the allison than the duramax most times.
So Mike is there anything else in the works to help keep the c3 assembly cool?
I know about the oiler I was just wondering if there was anything else in the works because sounds like the more cooling we can get the better.
the c3 oiler puts alot of fluid out on those clutches ............ i know because i forgot to tighten one of the lines and lets just say i had a big puddle in a short amount of time
i am shure mike has the specifics if you wanted them . i know my C-3's have taken a beating and i think the reason they are still holding well is from Mikes oiler .
great posts Mike, I love reading information on all of this... That was one of the best tech threads I have ever read. thanks again:hug:
We've gone beyond what the Alto red Eagles can hold IMHO. I'm working with someone on a new clutch lining. Wish me luck.
We've gone beyond what the Alto red Eagles can hold IMHO. I'm working with someone on a new clutch lining. Wish me luck.
So maybe it is a good thing I have to wait a bit on the tranny build. Regaurdless of what you use I know it will be worth the money, if they are good enough for you than I know it will be good enough for me.
Best of luck with your new clutches