Automatic Transmission 2-Speed thru 10-Speed GM Autos | Converters | Shift Kits
Sponsored by:
Sponsored by:

Why do i keep buring up 3-4 clutchpack

Thread Tools
 
Search this Thread
 
Old May 20, 2004 | 12:29 PM
  #41  
zippy's Avatar
TECH Veteran
 
Joined: Sep 2003
Posts: 4,540
Likes: 0
From: Las Vegas, NV
Default

Originally Posted by Rock-On
Page 62 figure 110, whats the date on that book?? drilling holes alone will not take away centrifugal apply while it helps in the hydro department, it does little for the cultchs, this is where your clearance comes into play. secoundly, the stock clutch steels are .106,with .74 frictions. we've had ample luck going to the .94 steels (4l65e) and blues with the 4l65e thickness of .64. you get the best of both worlds here. have your top plate cut and open the clearance up. The 9 pac alto red eagle clutchs......are to thin, but seem to work great in towing applications, I've only run about 10 z-pacs still not enough info to form an opinion, from the outset they look okay.
The biggest problem with these trannies here I go again...is LINE RISE...or lack thereof. There are 11 input controls and 8 output controls on this trans all of them haveing an effect on line rise and shifting of this trans.Thats not mentioning any of the hydralic controls,even your filters have to do with line rise. All of this must be performing flawlessly. And none of it can be left out of the picture with reguards to 3/4 burn up.
I really do agree with the builder comment.....along with that is the shop owners, who's only concern is the bottom line. I do hope this helps and is not intended as a slam on anyone. yall have a good day.....Dave


Reply
Old May 20, 2004 | 12:48 PM
  #42  
CamaroSS_2002's Avatar
TECH Regular
iTrader: (4)
 
Joined: Nov 2001
Posts: 496
Likes: 0
From: Fort Worth, Tx
Default

Originally Posted by Rock-On
Page 62 figure 110, whats the date on that book?? drilling holes alone will not take away centrifugal apply while it helps in the hydro department, it does little for the cultchs, this is where your clearance comes into play. secoundly, the stock clutch steels are .106,with .74 frictions. we've had ample luck going to the .94 steels (4l65e) and blues with the 4l65e thickness of .64. you get the best of both worlds here. have your top plate cut and open the clearance up. The 9 pac alto red eagle clutchs......are to thin, but seem to work great in towing applications, I've only run about 10 z-pacs still not enough info to form an opinion, from the outset they look okay.
The biggest problem with these trannies here I go again...is LINE RISE...or lack thereof. There are 11 input controls and 8 output controls on this trans all of them haveing an effect on line rise and shifting of this trans.Thats not mentioning any of the hydralic controls,even your filters have to do with line rise. All of this must be performing flawlessly. And none of it can be left out of the picture with reguards to 3/4 burn up.
I really do agree with the builder comment.....along with that is the shop owners, who's only concern is the bottom line. I do hope this helps and is not intended as a slam on anyone. yall have a good day.....Dave
Good info Dave, --- BTW we met one time when I drove up from Fort Worth ,on short notice, with my friend on to buy that Corvette Servo a few months ago... I was the younger guy --- Servo worked great BTW
Reply
Old May 20, 2004 | 02:50 PM
  #43  
00SS4780's Avatar
TECH Addict
iTrader: (3)
 
Joined: Jul 2002
Posts: 2,589
Likes: 2
From: Weaverville, NC
Default

I have a B&M super cooler. I watch the temps and they are never high untill the clutches are burnt up and 3 and 4 are mia.
Reply
Old May 20, 2004 | 05:11 PM
  #44  
Rock-On's Avatar
Banned
iTrader: (-2)
 
Joined: Nov 2003
Posts: 271
Likes: 0
Default hey

Hey, May I ask where you have the sending unit pluged in at? Alot of guys are trying to run the gage through the pressure port, this is the (plug) bolt by the manual valve on the side(driver side) of the transmission. This isn't a good location, plumb into the top cooler line coming out of the transmission.....about 6" or so from the trans...Here your catching the fliud as it comes from the torque convertor...the hottest it'll be . Hope this helps Dave
Reply
Old May 20, 2004 | 06:50 PM
  #45  
00SS4780's Avatar
TECH Addict
iTrader: (3)
 
Joined: Jul 2002
Posts: 2,589
Likes: 2
From: Weaverville, NC
Default

Yeh I have it on the side of the tranny (pressure port), but figured I would atleast be able to keep an eye on and see how it ran there. That way when it would go up I would notice it running higher. Thanks.
Reply
Old May 21, 2004 | 03:31 AM
  #46  
Hit Man X's Avatar
TECH Veteran
 
Joined: Mar 2003
Posts: 4,492
Likes: 0
Default

Rock-On...

So what to do about line rise? How do you (if you can) over come this problem? This is quite interesting to me.

Poor line rise is insufficient fluid no?
Reply
Old May 21, 2004 | 11:03 AM
  #47  
Rock-On's Avatar
Banned
iTrader: (-2)
 
Joined: Nov 2003
Posts: 271
Likes: 0
Default hey

Hey hit man, Poor line rise is better explanied as insufficient fliud pressure.Think of it like this: you have a scale reading 0-100. Now at idle your scale will be lets say 0. as you accelerate your scale will begin to rise say 50 at half throttle, at wot it will read 100..............these are not the actual pressures......... with the above in mind, sitting at idle with a pressure gage installed on the pressure port your gage must read 0 (70), (now heres the part that throws the most experianced rebuilder)........floor the engine(slambing the foot to the floor) and let off. do this a few times never holding it to the floor. As you do this, watch your gage, your gage must follow your foot travel. it will read 100 (170-190). these pressures must be immidiate and responsive. If you have lazy line rise.....btw 9 out of 10 comming into my shop are lazy and non responsive, you'll have burned clutchs every time.As you increase speed in your trans, your tranny has to increase pressure to keep up with the demands, thus your tranny must respond with higher pressure, if your pressure is coming in to late you'll have long slipping shifts,if it comes to early you'll have short hard shifts, i'd rather have early than late but I'm not a big fan of that either. I hope this helps, if you've got any questions or this isn't clear enough drop me a line and i'll try to help....oh sorry about the spelling ...have a good day ...Dave
Reply
Old May 21, 2004 | 12:37 PM
  #48  
jimmyblue's Avatar
Moderator
iTrader: (11)
 
Joined: Mar 2002
Posts: 12,604
Likes: 7
From: East Central Florida
Default

3-4 shift is not torque managed. 3-4 line in my '02
stock TM table is all zeroes. Do you shift 3-4 under
WOT?
Reply
Old May 21, 2004 | 02:54 PM
  #49  
Hit Man X's Avatar
TECH Veteran
 
Joined: Mar 2003
Posts: 4,492
Likes: 0
Default

jimmyblue... do I shift 3-4 at WOT? Hell no, I'd be going well over 140mph at that time.



Rock-On... good info. I will shoot ya a PM regarding more q's I have about the 4L60E.
Reply
Old May 21, 2004 | 03:23 PM
  #50  
Kevin 276's Avatar
TECH Apprentice
 
Joined: Jul 2002
Posts: 306
Likes: 0
From: Ohio
Default

Originally Posted by Rock-On
Hey hit man, Poor line rise is better explanied as insufficient fliud pressure.Think of it like this: you have a scale reading 0-100. Now at idle your scale will be lets say 0. as you accelerate your scale will begin to rise say 50 at half throttle, at wot it will read 100..............these are not the actual pressures......... with the above in mind, sitting at idle with a pressure gage installed on the pressure port your gage must read 0 (70), (now heres the part that throws the most experianced rebuilder)........floor the engine(slambing the foot to the floor) and let off. do this a few times never holding it to the floor. As you do this, watch your gage, your gage must follow your foot travel. it will read 100 (170-190). these pressures must be immidiate and responsive. If you have lazy line rise.....btw 9 out of 10 comming into my shop are lazy and non responsive, you'll have burned clutchs every time.As you increase speed in your trans, your tranny has to increase pressure to keep up with the demands, thus your tranny must respond with higher pressure, if your pressure is coming in to late you'll have long slipping shifts,if it comes to early you'll have short hard shifts, i'd rather have early than late but I'm not a big fan of that either. I hope this helps, if you've got any questions or this isn't clear enough drop me a line and i'll try to help....oh sorry about the spelling ...have a good day ...Dave
Dave,

Awesome job with the explanation...I have learned alot.
Reply
Old May 21, 2004 | 03:44 PM
  #51  
offaxis's Avatar
10 Second Club
20 Year Member
iTrader: (19)
 
Joined: Jun 2002
Posts: 2,062
Likes: 1
From: L-Town N.Y.
Default

Originally Posted by Rock-On
Hey hit man, Poor line rise is better explanied as insufficient fliud pressure.Think of it like this: you have a scale reading 0-100. Now at idle your scale will be lets say 0. as you accelerate your scale will begin to rise say 50 at half throttle, at wot it will read 100..............these are not the actual pressures......... with the above in mind, sitting at idle with a pressure gage installed on the pressure port your gage must read 0 (70), (now heres the part that throws the most experianced rebuilder)........floor the engine(slambing the foot to the floor) and let off. do this a few times never holding it to the floor. As you do this, watch your gage, your gage must follow your foot travel. it will read 100 (170-190). these pressures must be immidiate and responsive. If you have lazy line rise.....btw 9 out of 10 comming into my shop are lazy and non responsive, you'll have burned clutchs every time.As you increase speed in your trans, your tranny has to increase pressure to keep up with the demands, thus your tranny must respond with higher pressure, if your pressure is coming in to late you'll have long slipping shifts,if it comes to early you'll have short hard shifts, i'd rather have early than late but I'm not a big fan of that either. I hope this helps, if you've got any questions or this isn't clear enough drop me a line and i'll try to help....oh sorry about the spelling ...have a good day ...Dave

How would you fix or non responsive lazy line pressure ?
Reply
Old May 21, 2004 | 05:49 PM
  #52  
Hawkn01's Avatar
10 Second Club
iTrader: (1)
 
Joined: Aug 2002
Posts: 1,338
Likes: 1
From: Hampton Roads,Va.
Default

The guy that does my transmissions installed a differant spring and plunger in the pump itself. He called it a rev kit. He said the stock pumps at higher RPMs flucuate to much and don't hold a steady pressure. The kit is designed to keep the pressure more consistant at the higher RPMs to help the 3/4 problem.
Reply
Old May 21, 2004 | 07:41 PM
  #53  
Rock-On's Avatar
Banned
iTrader: (-2)
 
Joined: Nov 2003
Posts: 271
Likes: 0
Default

Originally Posted by offaxis
How would you fix or non responsive lazy line pressure ?
First we have to find out what is causeing it, it could be a control problem, or an internal problem, it would depend on what the gage is or is not doing....much like a vacume gage for trouble shooting an engine.
You see it here all the time "I got 85000 miles out of the original transmission, this piece of **** only went 2000 miles then 3/4 burned up." there soluation to the problem is to install a 350. when the whole time it was their tps, or mass air flow or a bad ground. Putting another set of clutchs in is not the cure. Adding a 350 maybe but it seems extreme to me considering we're at 2.00 a gallon. You've got to find the problem and fix it.
Their are many qualified persons who can trouble shoot these problems, even more who can not! Yes like hawkn01 said these pumps cavitate on the higher rpm band really bad, but what I see more than this is poor line rise.
Note: cavatation is a high rev situation, running a line check don't quite take in this problem, however it will give you a flat spot on top, when performing a line chek your not holding that rev long enough.
It is my hope that this is clear and is not intended as a slamb to anyone, I appricate you all and this fourm thanks ........Dave
Reply
Old Jun 10, 2004 | 11:02 AM
  #54  
Spellbound's Avatar
11 Second Club
 
Joined: Feb 2002
Posts: 639
Likes: 0
From: Norcal
Default

ttt, gettting ready to do a rebuild.
Reply
Old Jun 10, 2004 | 01:55 PM
  #55  
cablebandit's Avatar
9 Second Club
20 Year Member
iTrader: (37)
 
Joined: Nov 2001
Posts: 7,903
Likes: 1
From: Cleveland, OH
Default

Dave, I know NOTHING about autos. I bought one from a member here (used) that is supposed to be pretty durable. before I go out and thrash it, could you tell me where to get a line pressure gauge, where to tap for it and how to test it? I'd like to know what it is doing now before it gets abused.

As far as setting up the trans in ls1edit, it seems ideas are all over the place...dunno where to start.
Reply




All times are GMT -5. The time now is 11:23 AM.