Does anyone have any 4l60e performance rebuild tips to make it last longer.

This is the third time I need to get my 60e built. The guy I am taking it to is a certified tramsmission mechanic but he isn't really hip on performance. THe last time I got it rebuilt I put #K2 from http://www.transmissioncenter.net/4L60E.htm along with #K2TD and #K2Tc. THis still didn't prevent 3rd and 4th burning up.

 

Building a 4L60E correctly is about more than what parts you use. There are many special techniques that I've learned over the past 17+ years.

Much of what I've focused on has been clutch/band life. Through all of our research. we've eliminated the 3-4 clutch failure problems. Unfortunately, many "generic" transmission builders/shops still don't know what needs to be done to the 4L60E to make it last.

Frank
CPT

 

Please......share with us......the benifit of your knowledge......oooh transmission zen master ......the deep secrets of keeping the 3-4 clutch pack from frying every two months......enlighten the uninformed ......ooooh zen master.......


Mec

 

Well, Mec...the first thing you'd need to do is throw that vacuum modulator away.

Frank
CPT

 

Not the Zen master...but I'll throw my two cents in...Stay with your Vac. mod set up...these transmissions work fine with either...just some folks don't know how to set up the vac. mods. What ever you choose for modulation will work if your going the electronic route you'll need to get brushed up on your troubleshooting skills...you'll have to test and pass eight to eleven external transmission controllers.

Once everything has been tested okay then the biggest thing you can do for your trans is get the pump slide to stop centering or stop (hi-rev) cavitations. This can be done several ways using bigger (stronger) slide springs or staking the slider. I use a hi rev spring from transgo, works perfectly and you can get it just about anywhere.

The next thing to do is center your drums with new stator bushings...go get the wider ones they'll hold more revs.

Then you got to change out your Teflon input seals. Be careful here purchase the install tools and be careful not to cut or burn the seals from improper use of the tools.

Now that you have these areas shored up you can start on the drum...take the steel pistons throw them away....save the steel forward piston as you'll want to re use it. Replace the other piston with early style, lip seals are longer and will not leak as much under load. They also absorb some of the apply friction.

Now that you have this done throw the anti applies springs away, there are 5 of them per drum. You can either add transgo anti apply spring or if you prefer use the stockers...if you choose to use stock drill the 3-4 apply chamber with a .062 drill to allow trapped oil to leak out. it's really easier to add heavier springs, when you start drilling sometimes you'll make a mistake...Also if you want you can knock out the orifice casuals out of the drum and have it welded shut. It's your choice.

When you build up the drum start with a no number "finger", some are stamped 7 other are 4...we use the no numbers and hand sand them down to fit the 3-4 apply ring, with the 3-4 piston installed, install the apply fingers, then the clutch apply plate hold down on the apply and make sure that the apply plate touches the set area within the drum and the apply fingers have "no gaps between the apply plate and fingers". Any gap here and your slowing down your apply time. Very important for a healthy 3-4 clutch life.

What clutch to use?? What ever you want... I use the 4L65E clutch set up we have over 300 passes and 50,000 street miles on these clutches and we use them in our 845 rwhp and our 1045 rwhp cars. Clutches are holding up well in both...bout 50 passes. I stay away from the thin clutches and steels opting instead for the thicker cooler steels/clutches. I like them because you can get them anywhere and they are a stock item you can order them from any GM dealer ...in today’s world that’s cool.

Last but not least run your pressure at no more than 230 psi line. We run 90 on the low side and 230 on the top ...whets nice about the vacuum mod is you can go to the track and disconnect your vacuum line and get full line pressure while your at the track ...do your runs and your assured to have full line pressure, the whole time your there ... Plug it back in and drive home. Low pressure is the big killer of the 3-4 clutch. That’s just one of the benefits of vacuum modulation.

I hope this answers some of the questions, I’m sure I left some stuff out, but you get the picture.And I do hope this helps …Dave

 

Frank, I am having good luck with the vaccum mod on mine and many others I,ve set up. I,m sure you have had experience with them to make you say that. I can respect that, but until I start having problems I think I will continue with them when the customer opts to spend a little extra at my urgence. Pressure tests and durable units are showing me that I,m not making a bad recomendation. Dave, thanks for the input. The things you stated helped me understand that I am on my way to being a better builder. About the only thing I do different is use the NoYoYo 5500+RPM kit on the pump slide. Comes with a good spring and better rings. Pressure tests good past 6800 rpm. Also I am still using the steel pistons when I can, I've had problems with the aluminum ones cracking. I dont have a cryo source yet. Frank, Dave, & Dana, I watch all of your posts closely for tips and advice when you care to provide it. You are all Zen Masters

Mec

 

thanks for the advice

 

Hey Mec , Thats what I'm talking about...The no yo yo kit, is excellant for the street and strip, we've had some springs wound over here that allows us to creep up to 9000 rpm's. Very seldom go there but we're working on differant pressures. Mec have you ever noticed that you've never ran into a broken forward piston in the 700's?? For the sake of arguement should I say "very seldom". Have you had this same "experance"? We've pretty much came to the conclusion that the forward pistons are breaking from pressure spikes, that why we re run the steel pistons. Run one up to 270 psi line and see what happens....even with cryoed pistons. Excuse my spelling I'm in a hurry... gotta go take my meds... Hope this helps...Dave