flynlow3

iTrader: (2)

I have been pretty hard on my trans and am in need of a rebuild again. I am looking for advice on a few things and know there are many good builders on this site with helpful advice. First off, I am a diy kinda guy and I am not sending it anywhere. I like to get my hands dirty and dont mind doing it a few times to get it right. I have pulled it 4 times already and for some reason i keep burning up the 3-4 clutch pack. I am assuming my pressures are off. I will include what parts i have used in the past. I started out with a carbon wide band. I don't think this was the best choice but it worked for a while. The alto clutch pack was my first one after the factory one went out on me. It lasted about 3k miles. I rebuilt it again and used a z-pack style. No luck. 2k miles later it was shot. I believe the borg warner hi energy set is what i have in it now and it is starting to slip. I have used all of the best parts i could find and I am confident i have something off as far as my pressures go. I do have a transgo stage 2 shift kit in it. I stuck with the factory 4 pinion planetary but am looking at a gm 5 pinion when i tear it down this time. Anyone want to give me any insite other than take it to a shop please?

flynlow3

iTrader: (2)

Im putting down about 468 rwhp. I have heads and cam package with N20. My rear end is a 3.42.

The trans works great and shifts very firm but doesnt last. I ran low 12's with it but it seems as though sometimes it cant make up its mind on locking into overdrive. When the cruise is set sometimes it goes back and forth. I had the converter rebuilt twice. It is a yank 2800 stall.

I had all settings reset to factory by a shop and they said the car would relearn its shift points ect. my car did shift at 6200 RPM at WOT and revlimiter was 6600.

I do not recall what my pressures where but the guy who tuned it said it was good. I think i need to put my torque managment back in the computer because that was taken out.

One reason i think pressures wrong...It shifts great when I first start driving it. shifts firm. once the fluid gets warmed up it seems as though it stops shifting as hard. I do have a transcool and it has not gotten hot so that is not an issue.

WE TODD DID

iTrader: (2)

You have to realize that replacing burnt clutches doesn't fix anything. The type of clutches you are using are not the issue either. You need to find the source of your problem. What steps/ mods have you done to help with the 3-4's? What kind of power and weight is your vehicle? Does your drum still have the check ball? Have you checked for a leak in the drum around the input shaft splines? What type of sealing rings are you using?

flynlow3

iTrader: (2)

I realize that replacing the clutches is not fixing the problem. They are coning really bad though each time.

I rebuilt this unit with a guy who rebuilds them. I do not recall what he does to the pump but he did state something about modifying it. For better lubrication?

It was pressure checked every time and it came back fine everytime.

there is a seal that is molded on the newer units that he replaced with an older style one because it was loose. thought maybe that was the problem. Its been a while so i am trying to remember everything.

My car is a c5 corvette. Im not sure of the weight. but convenced that the tuning is my issue. My tuner said that taking all the torque managment out would be fine on a built trans. and that i would get better track times. Yes that is true but i think that by not allowing it to pull torque between shifts is destroying my clutch packs and bands. Thoughts?

346ci

By chance did you pull out the little spring returns for the 3-4 clutch to firm up the shifts. If so that will cause your clutches to drag.

flynlow3

iTrader: (2)

I did a ton of research and am building it step by step beside someone who does this for a living. I like to learn and that is what I am doing. I take pride in that and yes...The converted and lines where flushed. I had the converter rebuilt twice. once by yank and the other time by a transmission place locally.

72blownvert

Check the ball & capsule in the servo bore for leakage & you might want to go with a 46MOD modulator from trans-go that takes care of alot of line rise issues.This gets rid of your EPC solenoid & now your line pressure equals engine torque it works great.Sometimes the factory set up can not keep up and when you get on & off the gas line pressure becomes unstable and fluctuates to much & when that happens the first thing to go is the 3-4 clutches.

flynlow3

iTrader: (2)

Thank you very much! Im putting together a parts list and reading on that now! This is eactly the kinda help i was looking for!

Great suggestion!

MattysTA

iTrader: (18)

a 2 pinion planetary? i have never heard of anyone doing that. have you ever rebuilt a trans youreself? cause i have and it seems to me that you have no idea what your talking about. sounds like your just regurgitating things youve "heard"

MattysTA

iTrader: (18)

hmmm lets see "ive heard" doesnt really mean you learned anything, it could be good or bad information but mostly its "Hear say". and considering youve been a member for not even a year while ive been here for 6 yeah im pretty sure ive seen a few build sheets before...

flynlow3

iTrader: (2)

I think i found out today what my problem is. After talking with several other builders, it sounds like my pump is the issue. It is a 13 vane pump but is only good up to about 5800rpms. I have my shifts set at 6200 at wot. From 5800-6200 the pump is not suficient enough leaving me with low line pressures at high rpms. In result burning up my soft parts.

Thanks for all your help guys. anyone with info on what parts to get during this build would be greatly appreciated. I want the best wide band and 3-4 clutches i can get.

ordering a transgo 46mod.

please add to my list of things to get im kinda pumped here!

WE TODD DID

iTrader: (2)

That is not your problem.

flynlow3

iTrader: (2)

Wee Todd Did,

What is my problem then? I think its a pump issue. Enlighten me please?

samson_420

iTrader: (1)

Hmmmm, I say the pump also. . . . But most likely due to clearances.


But, that's my opinion. I only built one AT(yest it did work).

WE TODD DID

iTrader: (2)

The problem is the builder. You have yet to let us know what sort of steps you have taken to help with the 3-4 clutches to live, if any at all. What type of sealing rings are you using, what shape is the pump stator in, have you checked the 3-4 circuit in the drum for a leak, does the drum have a bleed hole or check ball, what springs are in the drum, what have you done for accumulation for 3rd gear, etc....etc....etc....

MattysTA

iTrader: (18)

first of all jerkoff, my statement about being on here for a long time has nothing to do with me being on the internet longer, it was merely to show you ive been here long enough to see people post their trans build sheets before. secondly i posted to that other kid about checking his tranny's dipstick because it seems like he was doing it incorrectly. apparently you have a hard time comprehending sentences. And third im no kid im 33 and since you like to use that procedure on 63 year old women that is pretty nasty. you obviously cant handle a disagreement and have to refer to personal attacks right away.another ethug with a keyboard. your a jackass.

w1982ta

One thing to check is the drum itself. We've had input drums that actually slip on the shaft that is pressed in. The only way we discovered this was once in the parts washer the heat expanded the drum and the shaft just slid out. Also make sure you put the thin o ring in the drum itself.

flynlow3

iTrader: (2)

Thank you guys very much for this helpful info. Im printing it off and what i dont understand, Im getting a hands on explination with Jessie the guy who helped me build it.