building a 4l80e for 450hp and towing

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L31MaxExpress

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I find 4th to be fairly useless to bring a trailer up to speed to begin with. My 4th gear for the most part stays locked once it's locked or downshifts right to 3rd. The window for it to unlock and stay in 4th is pretty narrow but it will stay unlocked while going up through the gears.

Mine was worthless period with 3.73s and a 30.5" tall tire. Works GREAT now with a 5.13 gear. I have only found a few places on back roads running 60 mph or under that require a downshift to 3rd.
 

99burbK2500

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That bu52hd sounds interesting. I run a 4:10 gear and a 31in tire right now. plan on adding a 5in tuff country and 35s. might need a gear change then we will see. I'm happy with how the transmission works right now with the tune my tuner put in it, cant recall if the flare is gone or not. been a few months since I drove it last. engine parts are finally done at the machine shop. now to put it all back together. I'm gonna order the hd2 kit as soon as I get it running. gotta get the short block back together, the ls6 springs in the heads and the btr stage 3 truck cam in. ready to drive it again. its refreshing to hear the 4l80 will hold power for a long time with something as simple as a hd2 kit. we will see how mine severs the test of time. I do have a stock rebuild kit for it already, if it dies ill just use that.
 

Tomcat58

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I was planning the same thing. Towing a boat and a heavy truck camper. I went with a Jakes Stage 2 kit and they let me down big time. Maybe these problem were just my experience with Jakes but a google search for Jakes Performance or Jakeshoe and add reviews and complaints will show you I am not alone in my complaints.

I posted my experiences on rebuilding my 4L80e and what I went thru with jakes on the end few post. If i did it again i would just get stock friction and steel plates which are borg warner high friction. That is what most of the high horsepower builder use... The rest of the build would be to follow this guys step by step videos.. ... he takes you thru a stock rebuild or a heavy duty rebuild in the video. Actually he sells a kit that I sure would work just fine. He sure saved my butt ... Transmission bench website: https://www.transmissionbench.com/videospage.html

My story/posts https://www.gmfullsize.com/threads/time-to-learn-how-to-rebuild-a-4l80e.315433/page-4
 

andy396

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I was planning the same thing. Towing a boat and a heavy truck camper. I went with a Jakes Stage 2 kit and they let me down big time. Maybe these problem were just my experience with Jakes but a google search for Jakes Performance or Jakeshoe and add reviews and complaints will show you I am not alone in my complaints.

I read through your story. I too went with Jake’s Performance and their Stage 2 kit. I wasn’t completely ignorant of what I was getting into by going with them. I’d read pretty much every post on the forums I could find. I was rebuilding a ‘00 4L80e so I got mostly all the correct parts. They did send the wrong sprag also but corrected the error pretty quickly and professionally for me. They were also kind enough to send me a few extra check balls that I lost somewhere in my garage during the disassembly process. I can put myself in their shoes and can see how frustrating and time consuming it is to deal with novices. I watched every YouTube video I could find and had two paper repair manuals I was referencing the whole time. I tried to do as much as I could on my own and only planned on calling Jake’s if I was desperate. Thankfully, I think I was successful (only 500mi so far). But you’re 100% right, if you don’t have the time or margin to support selling kits to amateurs state that up front or establish some kind of hourly rate for tech support.

If I ever do another one, I’ll also likely just get the parts independently as you suggested. In the end, the only modifications I made were the dual feed and slightly opened up the feed orifices. Oh, I did use the thrust bearing on the output shaft also, but it probably wasn’t necessary as it’s a 4WD tranny.

Link to my build thread with tranny mods details.

Andy’s 1995 CCLB 7.4L TBI to Vortec Swap
https://r.tapatalk.com/shareLink?sh...B-7.4L-TBI-to-Vortec-Swap.45295/&share_type=t
 
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