Quote:
Originally Posted by Ratchthed
I ran into this thread on a search a few minutes ago. We've been slammed here since the Holidays and I have not been able to follow some threads like I try to do ordinarilly. Sorry for not answering your question sooner!

420 H/P- 400 Tq. is not too big of a problem at all for a correctly "well built" 4L60E. The reason I said what I did in my 1st post here is that I personally, myself installed countless combinations of 3/4 clutches back when we were developing our unit a few years ago. I went through Raybestos Z-Packs like they were diapers on a baby. I went through the Alto Red Eagles dang near as often. Both have their place in the Transmission world... just not in this unit for High Performance applications.

Those comments are based on my personal experience. Obviously others have their own opinion.

I will say this in the fullest confidence I know how to say it.... We have not lost one single 3/4 clutch pack since I went to the Borg Warner High Energy clutches stacked tight. There are quite a few of them in the mid 10.xx's, stroker engines on Spray, N/A engines, forced induction, etc... pick one and we have built a 60E for it.

No doubt it is not just the clutches though.... Not long after I bailed on the idea of a non traditional clutch stack, I switched to a Vacuum Modulator instead of the EPC for controlling Line Pressure. The Vac Modulator provide a very linear pressure rise as opposed to the very inconsistant digital pressure rise produced by the PCM/EPC combination.

Another thing I did was to implement some changes with the way we managed the 2/3 hydraulics through trial and error. By the time I was satisfied that I had solved the riddle I had a stack of 3/4 clutches that was almost up to my knee. I kept them all for reference during our R&D program.

So you can see there is much more to it than just installing trick parts. And sometimes trick parts is not the answer.

I know the OP is going to a 6 speed from looking around here. I hate to see it because I know that a correctly well built unit is a solid solution to his Transmission woes.

Good Luck and here's to going faster in '08!

g
I know this is an old post but i just found it...I ended up with Playtoys burn up 3rd and 4th clutch packs 4L60E...So i am going to fix it at home. Is there a small rebuild kit just for the 3rd and 4th clutches???
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One of the keys to survival for the 4L60E is tight 3/4 clutch tolerances.

 

What do you mean? Total clutch pack thinkness, or with the pack installed taking some kind of drop measurement using the case??

 

clearance IMO should be in the .020 range and we do use the Z pack and with them have cars running every weekend and daily driver in the low 10s over a year to date .

 

thanks for the info BRO...

 

You are always welcome any time

 

I also use the Z-pack 3-4 and set them up at the lower end of the spec. I also throw the load release springs in the trash too while i'm at it, the only time I keep them is if the thing will see over 7k rpm regularly (and i dont mean 7100). Change the pump slide spring to the higher rpm unit too while you're at it. Look into changing the boost valve to a .500 unit while you're in there as well.

I had bad luck on my first 4l60e with the 9 friction 3-4 clutch pack, the steels (thin) warped from heat and closed up the clearance and burned the pack up in a hurry to say the least.

 

ws6t3rror This explanation is for High Performance Street use. The reason that you think that it is the thin steels causing the problem, is that you have a clutch material that will not hold enough oil. The clutch material must hold a certain amount of oil to dissapate the heat efficiently, otherwise if the clutch does not hold enough oil, then the clutch can start to glaze, which in turn starts to produce excess heat from the clutches slipping. Now with the clutches slipping, the heat buildup (which can be very quick) will distort the steels, and not the other way around. With the right clutch material, the thin steels would not warp, as the heat will be dissapated from the oil being vaporized on the shift. Gil Younger was the first who pointed this out to me back in 1994-5. Since then I have spoken to Borg Warner and Raybestos about this, and they said the same thing in most applications. Alto Reds or the Alto Commercial pack in high performance applications have not worked well here. The Raybestos Blue Plate Specials 1st generation did not do well either. The 2nd generation Blue Plate Specials should work better, according to Raybestos, only time will tell. The best that I have found over the last dozen years is the 2nd generation Borg Warner Hi-Energy 4L60E or the 4L65E clutches. The Raybestos Z-Pak seems to work good up to a certain HP, and this is exactly what Raybestos has said. There some builders on this board who have had success with the Z-Pak, and others who have not. But almost would agree that, the BW Hi-E's have done well in all applications.

 

I used the BW High Energy for a few years till my local supplier stopped stocking them. Started using the 4L65E plates (.066, hardened steel core) with great sucess. .025 clearance on .060 Kolene steels are working great for me, even on a 9 count set up with cars in the 10s. I get less notching with the 4L65E plate also. I'll keep using this setup till I find a reason not to I guess. Never really liked the Z-Pak but there are builders having good results with them. Go with what works for you.

Mec

 

PBA, thanks for the explanation on why they burn up. Its just when I pulled out the pack and pulled it apart all the steels looked like wave plates, so that just plain put me off of the 9 pack. I never really thought to ask why, because i'd had the stock 3-4 pack in before and it was holding up, just wanted to try the 9 pack to see if it would be better (it was alto). The other clutches I use are all the borg warner stuff. I just went with the z-pack on recomendation from a builder and so far I haven't had any failures with it. If they do start to give up on me at least I know where to go now.

Alot of the cars I mess with are just for me or my friends and they're all drivers or weekend toys. I just try and get internals in that will hold up to anything that would be done later.

What hp level would you say the z-pack is good to? I will always take input and suggestions from other builders though I may not use them, its good to have options if something stops working. I started with this after my local trans shop tried 5 times on a 60e I had in my chevelle. After 5 r&r I got enough sac to try it on my own, now I do a couple every year.

 

We have them in cars running at the 600 rwhp level without issue,

 

What does everyone think of the load release springs to keep 3-4 from dragging. Transgo sells stronger springs, and I know i'm not the only one who leaves them out entirely.

 

When using the HD springs from TransGo, you always remove the factory load release springs. The reason that TransGo made these HD springs, was so that you could use "any" 3-4 clutch count setup. The factory setup will only work with the stock clutch count setup. They serve "two" purposes. One, to keep the 3-4 clutches from accidently applying due to centrifuge and or crossleaks. Two, they help to bring off the 3-4 clutches quicker for a cleaner 3-2 downshift. I have used them since there inception.

 

Are you making mods to the hydraulics for 3rd gear then? When I used the stronger springs I always end up burning the pack eventually. When I stopped using them altogether my 3-4 troubles went away. I figured it was just another delay in the apply of the 3-4 just like a loose clearance.

 

I need to ask a question. I have done all the work to my car with the exception of tranny work.As of right now it's setting in my shop with 3/4 slipping badly and from past experience I know it's the 3/4 clutch pack.This will be the fourth time it has brunt them out.My car is making when spraying around 550 to 600hp....my question is should I try and replace just the 3/4 clutch pack or just swap it for a th400? The thing that bothers me the most is 1st and second is fine. I have never done any tranny work but I'm tempted to try it myself.The tranny that's in there now is a rock-on level4 it has lasted the longest around 1 yr.

 

What I have been tossing around is just buy a master rebuild kit from Raptor and try it myself.What would be your thought's? I would assume that the tranny has all the hard parts but thats only assuming.

 

ws6t3rror Yes, you must make changes to the 3rd gear circuit, and go with a .500 boost valve from TransGo. Then you should not burn up the 3-4 clutches.

 

PBA, I always go with a .500 boost valve anyway and a high rpm pump slide spring and hardened rings. But what mods exactly are you doing to the 3rd circuit. Always nice to compare notes, pm me if you dont want to make it public.

 

[QUOTE=performabuilt;9398105]You are always welcome any time[/
QUOTE]

How burnt should the trans fluid be, when just 3/4 clutches are toast?? My 4L60E has got SOME BURNT FLUID!!!!!! Makes me wonder what the heck happend. The trans only has 1500 miles and is a Century stage 1...

 

If the fluild is really badly burnt I would guess the trans may have more problems than just the 3-4 if the trans only has 1500 miles how long ago was it built Warranty?