Haven't pulled it all apart yet was just piddling at lunch and kinda said fack when I saw those. Gonna look into rebuild kits I guess. Only lookin to make 450 horsepower but I went with the 80e because 1. I want it to be reliable and 2. I could break an anvil with a pool noodle.

 

Fourth clutches look burnt and the steels have one hot spot in each of them. The overun clutches are toooast, most worn all the way through the friction material. The direct clutches actually look pretty good as do the intermediates. The direct housing has a step in it, is this normal or has the band caused this? I assume its normal because i can still see the machining marks around the drum from the factory. The band looks pretty good.

 

If the overdrives and over-runs are burnt, and the rest of the clutches look decent, that is indicative of a mis-adjusted shifter.

Drum sounds normal.

 

Awesome man I really appreciate you takin the time to give advice. I assume the ridge on the drum is machine to help the band track straight? I wouldnt be suprised if the shifter was out of adjustment based on the exterior condition especially with how beat up the pan was. Probly the condition they were tryin to fix with the fluid change and new filter.

 

I know this thread is old, but in the spirit of using the search function...

I have 5 4L80Es and a 6th for parts in my garage. I'm planning to build one for my 98 chevy with a 5.3 swap in the works, shelve another one with my Mk IV BBC, and build a 3rd for my wife's crew cab.

I'm starting with the 98 first. Why would you do the dual feed modification? specifically, what does it do for you? is this something that you should always do when rebuilding, or just for certain cases?

I'm building these for reliability/durability, not for racing or crazy off-roading. we pull a 7000Lb camper a few times a year, maybe I pull a car home on a trailer once in a blue moon, or I go to home depot and buy too much crap. that's the most I beat on this truck. I'm swapping to an 80E because they're super strong and hard to beat, and I want it to last a long time no matter which of those things I do to it.

with that in mind, I keep seeing great things about the sonnax reverse boost valve and case bushing, this dual feed mod, and the Borg Warner HE clutches. should I dual feed? or is this best left to the racing crowd?

 

I did the internal dual feed mod, sonnax boost valve and bushing. Why? Per smarter people it seems to allow more fluid volume and maybe pressure for the direct clutches. Well, something to that effect.

My goals were similar. I wanted the strongest trans possible for my platform. The 4l60e needed to go! This is/was my ultra reliable do everything suv. I needed to rely on it.

Other than that I stuck with BW clutches.

What else, get a tune to remove torque management, stops possible clutch slipping used to comfort people scared of a little thunk on shift. Also, for the love of God, remove checkballs 8 & 9 if internally dual fed. The dual feed I think causes less fluid to the reverse circuit and causes a slow reverse engage. I know first hand. Removing #9 fixes this very nicely. Hell I did this last week. #8 removal speeds up the 2-3 shift. I also have first hand experience and can say it does so nicely.

My other mod was to drill a small hole in the direct? drum to limit high rpm apply. Jake talks about this.

Other things to look into are the sonnax AFL reamer and kit. Its a high wear item.

Oh, get a big trans cooler.

End result for me is an 80e that really shifts fast. And now someone tomorrow is buying my Yukon right after I finished it all!

'bout all I have to say about that. /Gump

 

THANK YOU!!! that was a huge help. I'm going to keep looking and reading, but that's a big help to hear firsthand experience with the same goals I'm after. you rock!

 

sorry to ressurect an ancient thread. just happened to notice the spare tranny mentioned. i was cleaning valve body parts and lost the checkball that goes inbetween the pistons for a reverse circuit. i have the replacement sonnax o ring pistons cause the originals have aluminum bonded to the steel pistons so it wore the valve body a little. but i need a replacement checkball, not the 8 torlon ***** in the separator plate, but the single larger check ball that goes between those two pistons. im gonna see if the ***** out of my dirt bike ball bearing, if one of those might fit, will check on that tomorrow but if somebody had a spare valve body layign around and could rob that checkball from the reverse pistons and i could pay for an envelope to come to my place that'd be sick! thanks for ya'lls contributions, reading these forumns has helped me get this 4l80e rebuilt.