Allison 5sp: How to make a high HP allison live???

Righteyeblind

Member
Aug 29, 2008
712
0
16
Fairbanks, AK
C3 clutch is only 40% loaded.

Well it seemed to really slip at this shift so I let out of it. Checked my fluid and changed my spin on. Then went to make another pass and while I was spooling at the line as soon as the chargers started to light it just free revved. CEL came on p1721, cleared the code and backed out off the track
 

Righteyeblind

Member
Aug 29, 2008
712
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Fairbanks, AK
call me crazy Ben, but isn't fluid dynamic? properties change between hot and cold conditions. there is a fill and exhaust, the exhaust is not "closed off" per se. with more volume there is more fluid starting behind the c1 apply plate when fluid starts to leak out. I know you run your c1 clearance the same as me bud, not sure why you wanted to disagree? I run .115"-.125"

.115-.125 after they have been run should be right. Between 16 clutches they gain .15-.20 in what I've seen
 

03badmaxxx

Ghost Element
Mar 1, 2012
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Mesa,AZ
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There's only two things that equate to holding power, 1) pressure 2) surface area of friction material.

To the OP - The reason I asked who's tuning is mainly because bad tuning can cause a variety of problems in a transmision ( see if everyday..Not saying yours is bad Tony, ruled out when i heard you tuned it) which leads the belief of builder error. Sure you didnt knick something going in ? I personally don't think you at the power level of worrying about how to make an allision live because many people beyond what you are pushing are'nt having issues with less product inside
 
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Righteyeblind

Member
Aug 29, 2008
712
0
16
Fairbanks, AK
There's only two things that equate to holding power, 1) pressure 2) surface area of friction material.

To the OP - The reason I asked who's tuning is mainly because bad tuning can cause a variety of problems in a transmision ( see if everyday..Not saying yours is bad Tony, ruled out when i heard you tuned it) which leads the belief of builder error. Sure you didnt knick something going in ? I personally don't think you at the power level of worrying about how to make an allision live because many people beyond what you are pushing are'nt having issues with less product inside[/
Just because I ran only 115mph doesn't mean that's all it's got. That was a shakedown to see how the trans would act.
I'm positive it was built right. It's not my first build or even my 20th. I've put together a lot of transmissions but this is my first high HP build and I have had nothing but issues. Maybe the pump is bad I don't know but it's not lasting. i know people out there have problems with their trans at bigger hp but everyone seems to get numerous passes before a tear down so that's why I'm confused. I drove it for 500 miles before taking it to the track and everything had been perfect until I put more power to it.
I don't think you can get much less inside. No billet parts with clutches and pressure modifiers.
 
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juddski88

Freedom Diesel
Jul 1, 2008
4,655
120
63
Chesterfield, Mass.
.115-.125 after they have been run should be right. Between 16 clutches they gain .15-.20 in what I've seen

If my memory is correct, there is .135" max travel of the apply piston. I burned mine up for two reasons before the dpc, one was the lathe that was used to cut my top plate wasnt capable of enough rpm to make a factory finish, and also I was doing roling burnouts at 40-120 mph tuning in 2wd....twistwd planetary and also smoked c2. I originally set my c1 to .125" and it didnt over-travel the piston. So I made a nicer top plate with new c1s and set it up again at .125" and it held up great.
 

DieselDummy

Dirt Dummy
Oct 13, 2011
238
0
16
NY
Did you just turn your switch up? Did you let it learn the new power! I know they don't like being beat on small tune to big tune without some learning. Just a thought.
 

DieselDummy

Dirt Dummy
Oct 13, 2011
238
0
16
NY
How did I know some Yaywho like yourself would bring nothing meaningful to this thread.
I HAVE an 01 TCM that knows TRACK only that says RACE on it. I SWAP it out for the big tunes at the track. All it knows is wide open.

Exactly, your comment has not a dam thing to do with what the OP is trying to find out, my first comment did!!! How did the OP know some Yahoo like yourself swaps TCM's at the track! Maybe in your case it doesn't need relearning, just ask your tuner he will tell you it does!!! like i said before, im just a Dummy!!!
 

LBZrcks

.........
Jun 2, 2007
5,297
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SoCal
Exactly, your comment has not a dam thing to do with what the OP is trying to find out, my first comment did!!! How did the OP know some Yahoo like yourself swaps TCM's at the track! Maybe in your case it doesn't need relearning, just ask your tuner he will tell you it does!!! like i said before, im just a Dummy!!!

He is the OP...