randall 32

iTrader: (3)

4L60E is slipping going into 3ed at WOT. What causes this?

Vince B

iTrader: (1)

Most likely you have a 3-4 clutch failure going on. It is one of the weak links in these units. Vince

Omega Doom

iTrader: (2)

time for the rebuild!

projectX

iTrader: (51)

Having same issue here only it bounces off the rev limiter 5x first...

ThreeHonks

iTrader: (10)

be careful with that... that can cause the pump drive gear to shatter and further hurt things

projectX

iTrader: (51)

I am gonna just have it rebuilt no more WOT for awhile...

randall 32

iTrader: (3)

Thanks for the replies. I already backed the shift speed down to help with the rev limiter but the slipping is getting worse. What is recomended for up grades on the rebuild. I plan on putting a vigilanty stall back in.

randall 32

iTrader: (3)

good for 500 rwhp plan on up grades later with a little extra built in

Macs98Z

iTrader: (16)

Are you planning on rebuilding it yourself? If so, talk to Vince about what he recommends putting in it. He built my trans and did an awesome job and has years of experience with the 4L60Es. However, I can tell you from researching this myself that, unless you have a lot of time and possibly money on your hands in case something goes wrong with your rebuild, a built trans from someone who has been doing this as their specialty is the way to go (and pick one who has a lot of experience with the 4L60E). Rebuilding an automatic is not like rebuilding an engine. If you do so much as simply putting a seal in uneven, backwards, or damaged, you could have another transmission failure and not only be taking it out again but also buying a rebuild kit again--at which point you have almost paid for a built transmission, not to mention the time you would have saved yourself. Another thing about getting a built trans is that these guys know all the tricks to building one for horsepower and longevity. They all have their own tolerances and adjustments from the factory specs to make these better built than GM ever did. JMO.

Either way, good luck and let us know what you decide.

randall 32

iTrader: (3)

Thanks for the input, a friend rebuilds trans but i know he doesn't know everything peformance wise about these so im trying to decide if there are mainly parts i can buy and have him put in or is ther a lot more to it than that.

Macs98Z

iTrader: (16)

Yes, there are parts you can buy. Look up 4L60E rebuild kits online, or do a search on here to see what everyone who has rebuilt theirs used. Parts are only half the equation, however. The other half is having someone experienced with 4L60E's rebuild it who knows the tricks and specs to set the clearances at to make it last longer and outperform the stock transmission.

Are you on a budget, and that's why you're looking at doing it yourself?

randall 32

iTrader: (3)

I understand what your saying, but like most of us on here i like to save money whenever i can. In this case i would most likly be better off using someone who is a expert on the 4l60e. A good trans is about 2g and a good stall is anouther 800. It starts to add up and i really need to get a cam too know what stall i need.